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Intraspecific variation in Bothrops neuwiedi snake venom: Influence of age and sex.

Snake venom is a complex mixture of molecules and is subject to intraspecific variations due to the influence of abiotic and/or biotic factors, one of which is the animal's ontogeny. Some studies have already shown the influence of age on the composition and properties of snake venom, but these variations are not uniform, and each species may exhibit a specific pattern of variation. Therefore, this study aimed to analyze the influence of age on the venom of Bothrops neuwiedi, using 5 age groups, differentiating between males and females. To this end, we analyzed the protein profile of these venoms (using SDS-PAGE, HPLC, and proteomic analyses); enzymatic activities (PLA2, LAAO, and proteolytic activities); coagulant activity, in vivo assays (MDH; LD50 and ED50), and immunorecognition tests (Western blotting and ELISA). Protein profile analysis showed that males exhibited a gradual increase in SVMP and PLA2 concentrations. Both sexes showed a decrease in CTL concentration and a loss of PLA2 activity, which occurred more gradually in males. Proteolytic activity did not show clear ontogenetic differences, but both sexes showed activity peaks in the 2-year-old and senile groups, with females exhibiting higher proteolytic activity than males. Regarding LAAO activity, it increased in males and decreased in females. Although the LD50 did not show age-dependent differences, the venom from the 1-year-old group took longer to cause death in mice but showed a higher hemorrhagic activity than seniles. Furthermore, more antivenom was needed to neutralize the venom from the 1-year-old group than the venom from the senile group; despite this, immunorecognition tests did not show significant ontogenetic variations. In conclusion, the venom of the snake B. neuwiedi undergoes ontogenetic variations with certain sexual differences, showing some peculiarities that have not been found in ontogenetic analyses of other species of the same genus.

Animals

Construction of an infectious clone of Spodoptera frugiperda densovirus and its biological characteristics.

Densoviruses are highly pathogenic to their insect hosts and have great potential for biocontrol. Spodoptera frugiperda densovirus (SfDV) was isolated from diseased larvae of Spodoptera frugiperda, while its biological functions remain unclear. Herein, we successfully constructed an infectious clone of SfDV. The S. frugiperda larvae transfected with the infectious clone exhibited anorexia, stunted growth, and reduced activity. Histopathological analysis further showed that the epidermis, fat body and trachea were infected instead of muscle and midgut tissues. Transmission electron microscopy (TEM) revealed that numerous virions of about 22 nm were distributed within both the nucleoplasm and cytoplasm of epidermal cells. Moreover, many virions were also found contained within vesicles in the cytoplasm. The replication kinetics of the rescued SfDV (rSfDV) was similar to that of the parental SfDV. The median lethal dose (LD50) and median lethal time (LT50) values of rSfDV were 6.63 × 107 viral genome copies (vgc), 5.23 d, respectively, which were also comparable to those of the parental SfDV. Taken together, the infectious clone of SfDV provides an important tool for further exploring the genome function, pathogenesis, and interactions with its hosts.

Animals

Aortoesophageal Fistula: Mending the Lethal Connection-A Systematic Review and Meta-Analysis.

BACKGROUND: Aortoesophageal fistula (AEF) is a rare, life-threatening condition with limited high-quality evidence to guide management. METHODS: We conducted a systematic review and meta-analysis of PubMed and Scopus through December 2025, evaluating survival and complication outcomes according to treatment strategy and morphological severity. Patients were categorized into 5 groups: TEVAR alone, staged TEVAR followed by surgery, primary open or hybrid surgery, TEVAR with esophageal stenting, and supportive/palliative care. Outcomes were pooled as proportions with 95% confidence intervals (CIs). RESULTS: A total of 167 reports representing 528 patients were included. Overall 30-day mortality was 31.2% (95% CI 27.0% to 35.7%) and 1-year mortality 41.2% (95% CI 36.2% to 46.4%). Infection occurred in 32.6%, reintervention in 20.2%, and recurrence in 13.2%. Staged TEVAR followed by surgery showed favorable survival (30-day 12.7%, 1-year 26.1%) but high infection (66.7%) and reintervention (43.2%) rates. TEVAR with esophageal stenting had the lowest early mortality (5.0%) but frequent reintervention (54.5%) and 1-year mortality of 33.3%. TEVAR alone demonstrated the lowest 1-year mortality among definitive strategies (25.5%) but notable recurrence (26.9%). Primary open or hybrid surgery carried higher early and late mortality, while supportive/palliative care had the worst outcomes. Morphological severity correlated strongly with mortality, infection, reintervention, and recurrence, with type IV lesions showing particularly poor prognosis. CONCLUSION: Despite contemporary management, AEF carries high early and late mortality. Definitive strategies, particularly staged TEVAR followed by surgery, offer improved survival but increased complications. Morphology-guided, individualized management is recommended.

Adult

Divergent responses of the gill, hepatopancreas, and eyestalk to acute alkalinity stress in Penaeus vannamei: Osmoregulatory compromise, metabolic trade-off, and endocrine disruption.

The expansion of aquaculture into inland saline-alkali waters is constrained by high carbonate alkalinity (CA), a severe environmental stressor for crustaceans. However, the systemic molecular mechanisms underlying its lethal toxicity remain poorly understood. In this study, we employed a comparative transcriptomic approach to investigate the tissue-specific responses of Pacific white shrimp, Penaeus vannamei, under acute lethal stress (48 h-LC50). We focused on three functionally distinct organs: the gill, hepatopancreas, and eyestalk. The results revealed a systemic but highly tissue-specific transcriptomic response. The gill, as the primary interface, exhibited severe structural impairment and critical failure of osmoregulation, highlighted by the significant downregulation of delta-1-pyrroline-5-carboxylate synthetase (P5CS). In contrast, the hepatopancreas initiates a profound metabolic trade-off, sacrificing growth-related pathways to bolster a robust antioxidant defense system, as evidenced by the activation of sulfur metabolism and high protein turnover. The eyestalk displayed a striking disconnect between hyperactivated stress signaling pathways (e.g., mTOR/FoxO) and the collapse of its protein secretory machinery, marked by the suppression of the ER translocon component Sec61. Collectively, our findings suggest that lethal alkalinity toxicity in P. vannamei results from systemic collapse driven by a complex interplay of osmoregulatory failure, metabolic trade-offs, and endocrine disruption. This study provides a comprehensive molecular snapshot of an organism at its physiological limit, offering novel insights into the adaptive strategies and ultimate tolerance boundaries of crustaceans in extreme environments.

Animals

Maternal transfer of nonylphenol drives oxidative, immune, and epigenetic dysregulation in zebrafish offspring.

Nonylphenol (NP), a widespread surfactant and endocrine-disrupting pollutant, poses significant ecological and public health risks globally; however, its transgenerational effects remain poorly understood. Using zebrafish (Danio rerio), we compared chronic maternal NP exposure (50 and 100 µg/L, 28 days) with acute embryonic exposure (0.22 µmol/L) during 0-3 days post-fertilization (dpf) to delineate mechanistic differences in toxicity. Maternal NP exposure produced severe developmental defects in offspring, including edema, axial curvature, impaired swim bladder inflation, reduced growth, cardiac dysfunction, and decreased viability. These phenotypes were accompanied by systemic molecular disruptions including oxidative stress, altered estrogen receptor (ER) expression, dysregulated mitogen-activated protein kinase (MAPK) signaling, and suppressed innate immune response characterized by attenuated neutrophil/macrophage density, reduced CD68 and complement protein C3 expression, diminished nitrite load, and downregulation of pro-inflammatory mediators at both transcript and protein levels. Maternal exposure further induced apoptosis and persistent epigenetic reprogramming (alterations in DNA methylation and histone-modifying enzymes), hallmarks of transgenerational toxicity. In contrast, direct embryonic NP exposure elicited morphological abnormalities without significant lethality, accompanied by induction of pro-inflammatory cytokines, nitric oxide (NO) synthesis, and MAPK activation, reflecting an augmented inflammatory response. These mechanistic contrasts reveal that maternal NP exposure is a potent driver of systemic, heritable molecular reprogramming, whereas embryonic exposure triggers acute inflammatory pathways. Together, our findings underscore the global relevance of NP as a transgenerational toxicant, advocating for its urgent inclusion in ecotoxicological risk assessments and regulatory frameworks.

Animals

Safety, tolerability, pharmacokinetics, and pharmacodynamics of oral JMKX003002 in Chinese healthy participants: a randomized, double-blind, placebo-controlled, single- and multiple-ascending dose, and food-effect phase I clinical trial.

OBJECTIVE: To evaluate the safety, tolerability, pharmacokinetics (PK), and pharma-codynamics (PD) of the sodium-hydrogen exchanger 3 (NHE3) inhibitor JMKX003002 in Chinese healthy participants. PATIENTS AND METHODS: This phase I, randomized, double-blind, placebo-controlled study included a single-ascending dose (SAD) study with seven cohorts (1 mg [n = 4] and 5, 20, 50, 75, 100, or 125 mg [n = 8]), a food-effect (FE) study with six sequence groups (25 mg twice daily, n = 4), and a multiple-ascending dose (MAD) study with two cohorts (10 mg or 20 mg twice daily, n = 10). RESULTS: JMKX003002 was well-tolerated, with mostly mild treatment-related adverse events. One Grade 3 diarrhoea occurred in each of the 50 mg and 125 mg groups. No serious adverse events were reported, and no participants discontinued or withdrew due to treatment-emergent adverse events. Most plasma samples were below the limit of quantification (0.2 ng/mL), with only transient detection of low concentrations, indicating low systemic exposure. JMKX003002 was primarily excreted in stool (79.9% recovered) and was undetectable in urine. The PD results consistently showed decreased urinary sodium and phosphorus, along with increased stool sodium and phosphorus, compared to baseline across all three studies. One day after discontinuation, stool sodium and phosphorus remained elevated relative to baseline in the MAD study. Mixed-effects model analysis in the FE study demonstrated significant food effect on stool sodium and phosphorus excretion. CONCLUSION: JMKX003002 exhibited favorable safety and tolerability with minimal systemic exposure. It effectively increased sodium and phosphorus excretion in stool. These promising findings warrant further investigation of JMKX003002 to evaluate its clinical benefits. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300070473). Registered on April 13, 2023; prospectively registered.

Adult

Therapeutic-drug-monitoring-based ATG Targeted Dosing Strategy in Unmanipulated Haploidentical Haematopoietic Stem Cell Transplantation: a randomized, multicenter, phase 3 clinical trial.

Anti-thymocyte globulin (ATG) has been a standard prophylaxis for graft-versus-host disease (GVHD). However, the pharmacokinetics of ATG in vivo vary significantly, and weight-based fixed dosing may not optimize efficacy while minimizing toxicity. We investigated the clinical results of a therapeutic-drug-monitoring (TDM)-based, dose-optimized ATG strategy versus weight-based fixed dosing in haploidentical haematopoietic stem cell transplantation (NCT05166967). Patients were randomly assigned in a 1:1 ratio to receive a targeted dose of ATG or a fixed dose of 10&#x202f;mg/kg. The primary endpoint was the 365-day graft-versus-host disease-free and relapse-free survival (GRFS). From January 1, 2022, to January 16, 2024, 204 patients were enrolled, with 102 patients in each group. The 365-day GRFS was higher in the targeted dose group (66.7%) than in the fixed dose group (50.0%; hazard ratio [HR], 0.666; 95% confidence interval [CI], 0.4456 to 0.9954; P&#x202f;=&#x202f;0.048). The cumulative incidence of moderate to severe chronic GVHD at day 365 was significantly lower in the targeted dose group (9.8%; 95% CI, 5.0 to 16.5) compared with the fixed dose group (22.5%; 95% CI, 15.0 to 31.1; P&#x202f;=&#x202f;0.026). Fewer grade 3-5 infections were reported in the targeted dose group (44.1%) than in the fixed dose group (70.6%; P&#x202f;<&#x202f;0.001). More patients in the targeted dose group achieved optimal ATG exposure (P&#x202f;=&#x202f;0.007) and superior CD4+ T-cell reconstitution (P&#x202f;=&#x202f;0.002). These findings support the clinical utility of a TDM-based individualized ATG dosing strategy that balances efficacy and toxicity for GVHD prophylaxis in allogeneic stem cell transplantation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05166967.

Humans

A phase I clinical study of the safety, tolerability, pharmacokinetics and pharmacodynamics of SHR-2106, an anti-CD40 antibody, following single intravenous or subcutaneous administration in healthy participants.

BACKGROUND: SHR-2106 is a humanized IgG1 monoclonal antibody that blocks CD40-CD40L interactions and has demonstrated immunosuppressive activity and graft-prolonging effects in preclinical studies. This first-in-human Phase I study evaluated the safety, pharmacokinetics, pharmacodynamics, and immunogenicity of single intravenous or subcutaneous doses of SHR-2106 in healthy adults. METHODS: This randomized, double-blind, placebo-controlled Phase I study enrolled healthy participants. Fifty-one participants were enrolled in seven cohorts and received five intravenous doses (50-1200&#x202f;mg) or two subcutaneous doses (300 and 600&#x202f;mg). Safety, serum pharmacokinetics, CD40 occupancy on B cells, and anti-drug antibodies were assessed using standard clinical and bioanalytical methods. RESULTS: SHR-2106 demonstrated a favorable safety and tolerability profile, and most treatment-emergent adverse events were mild to moderate laboratory abnormalities with incidence rates comparable to placebo. SHR-2106 exhibited nonlinear pharmacokinetics consistent with target-mediated drug disposition, with a dose-dependent increase in geometric mean terminal half-life following intravenous administration (1.83-10.7 days). Absolute bioavailability after subcutaneous administration was approximately 60%. CD40 occupancy exceeded 80% within 24&#x202f;h at all doses, with saturation duration increasing from 7 to 70 days across the intravenous dose range and remaining comparable between routes at matched doses. Anti-drug antibody incidence decreased with increasing intravenous dose and did not significantly affect pharmacokinetics or pharmacodynamics. CONCLUSION: SHR-2106 was well tolerated and achieved rapid and sustained CD40 engagement, supporting dose and route selection for Phase II studies.

Humans

Intervention components, training dose, and adherence in exercise-based prevention of hamstring strain injury in football: a systematic review and meta-analysis.

OBJECTIVE: To quantify associations between exercise-based prevention programmes and hamstring strain injury (HSI) risk in football participants, and whether training dose and adherence modify effects. METHODS: Six databases were searched to 1 October 2025. Randomised and cluster-randomised trials comparing HSI prevention programmes with usual practice or warm-up in football participants were included. Random-effects meta-analysis pooled risk ratios (RRs); subgroup analyses and meta-regression assessed effect modification. RESULTS: Fifteen trials (n = 7,465) were analysed. Programmes reduced HSI risk (RR = 0.51, 95% CI 0.36-0.71), with I&#xb2;=57% and a prediction interval crossing the null (0.18-1.40). Based on a control event rate of 7.8%, absolute risk reduction was 3.8% (38 fewer HSIs per 1000 participants; 95% CI 23-50 fewer). Effects were stronger for shorter interventions (1-6 months; RR = 0.43) than longer interventions (7-10 months; RR = 0.77; P for interaction=0.04), and for elite/semi-professional players (RR = 0.38) than amateur players (RR = 0.77; P for interaction = 0.02). Training frequency and weekly volume did not modify effects, whereas adherence did. High adherence (&#x2265;75%) was associated with lower HSI risk (RR = 0.36, 95% CI 0.28-0.48), whereas low adherence (<75%) showed no clear benefit (RR = 0.92, 95% CI 0.68-1.23; P for interaction <0.00001). Each 10% increase in adherence corresponded to an RR multiplier of 0.83 (approximately 17% lower RR). Certainty of evidence was low. CONCLUSION: Exercise-based programmes reduce HSI risk in football when implementation supports sustained adherence. Effects may be stronger in shorter interventions and elite populations, but evidence remains insufficient to differentiate programme types or components.

Humans

Association between fruit and vegetable intake and risk of depression: A systematic review and meta-analysis of prospective cohort studies.

Depression is a leading cause of global disability, and identifying modifiable lifestyle factors is a public health priority. We conducted a systematic review and dose-response meta-analysis of prospective cohort studies examining the association between fruit and vegetable intake and incident depression. PubMed, Web of Science, Scopus, Embase, and Google Scholar were searched through November 2025. Data on study characteristics, dietary assessment, outcomes, effect estimates, and covariates were independently extracted by two reviewers. Random-effects models were used to calculate pooled relative risks (RRs), and linear and non-linear dose-response relationships were assessed. Heterogeneity was evaluated using I2, and evidence certainty was rated with GRADE. Thirteen cohorts with 385,449 participants and 26,592 depression cases were included. Highest versus lowest combined fruit and vegetable intake was associated with a 37% lower risk of depression (RR: 0.63; 95% CI: 0.50, 0.80). Each 200&#xa0;g/day increase corresponded to a 16% risk reduction (RR: 0.84; 95% CI: 0.74-0.94). Separate analyses showed that fruit and vegetable intake reduced depression risk by 16% and 12%, respectively, with a non-linear dose-response for vegetables. These findings indicate that higher consumption of fruits and vegetables is associated with lower depression risk, supporting dietary strategies as a potential approach for mental health prevention. However, given the observational nature of the included studies, these results should be interpreted with caution, as residual confounding may partially account for the observed associations. Registration: This study was registered at PROSPERO (CRD420261279998).

Humans

Comparative Bioavailability of Trimodal (CTx-1301) Versus Bimodal Dexmethylphenidate Modified-Release Formulations in Adults with Attention-Deficit/Hyperactivity Disorder: A Randomized, Single-Dose, Crossover Study.

BACKGROUND AND OBJECTIVES: Attention-deficit/hyperactivity disorder (ADHD) is a chronic neurodevelopmental disorder that often requires sustained symptom control throughout the day. Although bimodal extended-release dexmethylphenidate (d-MPH XR) formulations provide initial and intermediate drug release, they may not consistently maintain therapeutic exposure into the late afternoon and evening. Trimodal formulations with an additional delayed release component may extend drug exposure later in the day, although this remains to be established. To explore differences in pharmacokinetic (PK) profiles between trimodal (CTx-1301) and bimodal delivery of d-MPH XR, a comparative bioavailability study was conducted at the highest and lowest doses for both formulations. METHODS: In this randomized, 4-period, crossover study, adults with ADHD received single doses of CTx-1301 (50 mg and 6.25 mg) and d-MPH XR (40 mg and 5 mg). Comparative bioavailability was assessed through adjusted geometric mean ratios for exposure parameters (maximum observed plasma concentration [Cmax], area under plasma concentration-time curve to last measurable concentration [AUClast] and extrapolated to infinity [AUC0-inf]), with a prespecified bioequivalence range of 0.80 to 1.25. Secondary endpoints included partial AUCs and safety assessments. RESULTS: The study population (N&#xa0;=&#xa0;45) was predominantly male (88.9%) and White (55.6%), with mean age of 29.6&#xa0;&#xb1;&#xa0;8.01 years. Adjusted geometric mean ratios comparing the primary exposure parameters (Cmax, AUClast, and AUC0-inf) for CTx-1301 versus d-MPH XR were within the bioequivalence range (0.80-1.25) at both the high and low doses. The CTx-1301-to-d-MPH XR partial AUC ratios were within the bioequivalence range from 0 to 9 hours post-dose. At later intervals (AUC9-12 and AUC12-16), adjusted geometric mean ratios exceeded the upper bioequivalence threshold, consistent with the expected contribution of the third medication release component. Dose proportionality was observed between the two CTx-1301 doses and two d-MPH XR formulations. CTx-1301 was generally well tolerated. The most commonly reported adverse events included tachycardia, insomnia, headache, nausea, and euphoric mood. The incidence of treatment-emergent adverse events was numerically lower with CTx-1301 than with d-MPH XR; however, no statistical analysis was performed. CONCLUSIONS: Key exposure parameters including Cmax, AUClast, and AUC0-inf for trimodal CTx-1301 were statistically bioequivalent to bimodal d-MPH XR. Interval&#x2011;specific PK analyses demonstrated higher exposure with CTx&#x2011;1301 during later post-dose intervals (9-16 h), consistent with the formulation's third release component. However, the clinical relevance of these PK differences requires further evaluation. CTx-1301 demonstrated dose proportionality and was well tolerated at high and low doses. REGISTRATION: ClinicalTrials.gov, NCT04138498; 19 September 2019.

Humans

A Phase I Study Assessing the Safety, Tolerability, and Pharmacokinetics of Yinfenidone: A Novel, Potent Drug for Idiopathic Pulmonary Fibrosis Treatment in Healthy Chinese Subjects.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease with a median survival of only 2-3 years after diagnosis. Yinfenidone (HEC585) possesses the potential to inhibit the proliferation of pulmonary fibroblasts, making it a promising candidate for the treatment of IPF. This study assessed the safety, tolerability, pharmacokinetics, and metabolic profile of Yinfenidone hydrochloride capsule in healthy Chinese subjects. METHODS: This single-center, randomized, double-blind, placebo-controlled, single ascending-dose trial included seven dose groups(20, 50, 100, 200, 400, 600, and 800 mg). Each group enrolled8 healthy subjects: 6 received Yinfenidone hydrochloride capsules and 2 received matching placebo under fasting conditions. Serial pharmacokinetic (PK) blood samples were collected pre-dose and post-dose, liquid chromatography-tandem mass spectrometry was used to analyze the plasma concentrations of Yinfenidone. Additionally, metabolic biotransformation of Yinfenidone in plasma were conducted in the 100 mg dose group. Safety and tolerability endpoints were monitored via physical examinations, vital signs measurements, clinical laboratory tests, 12-lead electrocardiography (ECG), and adverse events (AEs) documentation throughout the trial. FINDINGS: Yinfenidone was rapidly absorbed, with a median maximum plasma concentration (Tmax) of 1.8-3.0 hours, and had a mean half-life (t1/2) ranging from 31.9 to 62.0 hours. Within the 20-100 mg dose range, systemic drug exposure generally increased with ascending dose, above 100 mg, exposure increased less than proportionally to dose. Metabolite profiling in the 100 mg group revealed that the parentcompound predominated in plasma, with metabolic pathways including mono-oxygenation and N-dealkylation. All reported AEswere mild, classified as Common Terminology Criteria for Adverse Events (CTCAE) version 4.03 grade 1. No serious AEs observed; no subject discontinued the trial due to AEs. Single oral doses of 20-800 mg Yinfenidone hydrochloride capsules administered under fasting conditions demonstrated favorable safety and tolerability profiles in healthy Chinese subjects. IMPLICATIONS: Yinfenidone exhibited rapid absorption (median Tmax, 1.8-3.0 hours) and a long terminal t1/2 ranging from 31.9 to 62.0 hours in this single ascending-dose study, indicating that Yinfenidone can be taken once a day in subsequent clinical studies. Yinfenidone mainly exists in human plasma as the original drug and is metabolized through a variety of metabolic pathways. The AEs observed with Yinfenidone in this study, such as diarrhea, nausea, and dizziness, were similar to those reported with pirfenidone. Overall, Yinfenidone demonstrated a favorable safety and tolerability profile in this cohort of healthy subjects.

Adult

A review on the environmental distribution, toxic effects, bioaccumulation characteristics and risk assessment of short-chain chlorinated paraffins.

Chlorinated paraffins (CPs) are synthetic chemicals, widely used as flame retardants and plasticizers. As emerging contaminants, short chain chlorinated paraffins (SCCPs) have attracted tremendous attention due to their persistence, chronic toxicity, long-range transport potential and bioaccumulation potential. This review synthesizes global data on SCCPs' environmental occurrence, toxicological impacts, and bioaccumulation characteristics. SCCPs are ubiquitously detected in various environmental media, including water, sediment, air, soil, and biota. Ecotoxicological studies reveal that SCCPs have lethality, carcinogenicity, growth and developmental toxicities, organs toxicities and endocrine-disrupting effects across species, which pose risks to ecological systems and human health. In addition, the bioaccumulation effects of SCCPs in terrestrial and aquatic ecosystems were analyzed, and proposed the key factors affecting the bioaccumulation of SCCPs. Finally, the risk assessment of SCCPs contamination in the surface water and the soil was carried out, and all soil and most water bodies were found to be low risk. The present study could provide scientific basis and reference for environmental management of CPs products.

Paraffin

Donor Human Milk Utilization in a Level 1 Newborn Unit of a High-Volume Delivery Hospital: A Cautionary Tale.

INTRODUCTION: Donor human milk (DHM) is an alternative to formula for supplementation of breastfed newborns and has been associated with higher in-hospital exclusive breast milk feeding rates. Its use has increased substantially, most recently among term newborns, yet there is scarce data to describe patient characteristics and volumes administered. We aimed to characterize DHM utilization in our level 1 nursery. METHODS: We conducted a retrospective cross-sectional study of newborns discharged in 2022 from the level 1 nursery. Variables included sex, gestational age, birth weight, delivery type, hypoglycemia diagnosis, DHM volume, and length of stay. DHM use was compared across preferred language, race, ethnicity, and payer type using chi-square testing. RESULTS: A total of 10,432 discharges were reviewed-those transferred to Neonatal Intensive Care Unit (NICU) or another unit were excluded. Of 9,074 newborns receiving level 1 care, 1,094 (12.1%) received DHM. Newborns born between 35 and 37 weeks gestation, delivered by cesarean section, or diagnosed with hypoglycemia or small for gestational age were more likely to receive DHM (p < 0.05). DHM was also more common among newborns whose birth parent preferred the English language, identified as White or non-Hispanic, or had non-Medicaid insurance (p < 0.05). 6,552.6 ounces were consumed, with a total median of 3.9 ounces per newborn (dose range 2-50 mL). CONCLUSIONS: DHM use in the level 1 nursery varied by clinical and sociodemographic factors, revealing inequities. In addition, some doses exceeded recommended supplemental volumes. Future efforts should focus on ensuring equitable access to DHM, standardized dosing and discontinuation guidelines, and evaluation of impacts on exclusive breastfeeding rates.

Humans

Outcomes of patients with myelofibrosis treated with ruxolitinib and anemia-supporting medications.

OBJECTIVE: This post hoc analysis of the phase 3b JUMP trial evaluated addition of anemia-supporting medications to ruxolitinib in patients with myelofibrosis and anemia. METHODS: 101 patients with baseline hemoglobin <12.0&#x2009;g/dL initiated an erythropoiesis-stimulating agent (ESA) or danazol <3&#x2009;months post-enrollment and maintained ESA/danazol &#x2265;3&#x2009;months; 97% initiated ESAs. Patients enrolled in JUMP who had hemoglobin <12.0&#x2009;g/dL but did not initiate ESAs/danazol within 3 months were evaluated as an unmatched comparator. Total JUMP population data were also analyzed for spleen length (&#x2265;50% reduction from baseline) and symptom response (&#x2265;6.5-point improvement in FACT-Lym score). RESULTS: Baseline characteristics were similar to comparator JUMP patients (no ESAs/danazol within 3&#x2009;months, n&#x2009;=&#x2009;1242). Mean total daily ruxolitinib dose remained >25&#x2009;mg. Week 24 spleen length response was achieved by 37% of patients; 26% achieved symptom response, similar to the comparator population (28% and 26%, respectively) and comparable to the total JUMP population (N&#x2009;=&#x2009;2233). Outcomes were similar between the hemoglobin <12.0&#x2009;g/dL analysis population and patients with baseline hemoglobin <10.0&#x2009;g/dL (n&#x2009;=&#x2009;52). In all groups, hemoglobin levels increased after Week 4 following an expected initial decrease. DISCUSSION: This analysis suggests that patients treated with ruxolitinib and anemia-supporting care continued to receive optimal ruxolitinib dosing; spleen-length and symptom response rates in these patients were comparable to the overall JUMP population, the majority of whom did not have anemia. CONCLUSION: Results support use of anemia-supporting medications with ruxolitinib and may allow maintenance of ruxolitinib dose intensity in patients with myelofibrosis and anemia.

Humans

A New Highly Concentrated Insulin Aspart AT278 (500&#x2009;U/mL) Demonstrates Ultra-Rapid Pharmacokinetic and Pharmacodynamic Properties in Type 2 Diabetes Regardless of BMI.

AIMS: To evaluate the pharmacokinetics, pharmacodynamics, and safety of a novel U500 insulin aspart formulation (AT278 [500&#x2009;U/mL]; AT278-U500) compared with standard concentration insulin aspart (InsAsp [100&#x2009;U/mL]; InsAsp-U100) and U500 human regular insulin (HumIns [500&#x2009;IU/mL]; HumIns-U500). MATERIALS AND METHODS: This single-centre, randomised, double-blind crossover 12-h euglycaemic clamp study was conducted in 41 overweight and obese people with type 2 diabetes (BMI 25.0-38.7&#x2009;kg/m2) receiving a single subcutaneous dose (0.5&#x2009;U/kg) of AT278-U500 and InsAsp-U100. HumIns-U500 was consecutively studied open label in a 24-h clamp. RESULTS: AT278-U500 exhibited a significantly faster insulin absorption than InsAsp-U100 and HumIns-U500 (t Early50%Cmax: 9&#x2009;min vs. 35&#x2009;min vs. 55&#x2009;min), leading to a significantly higher glucose-lowering effect within the first hour (AUCGIR,0-60min) compared with both InsAsp-U100 (treatment ratio 2.02 [95% CI 1.64; 2.50]) and HumIns-U500 (3.91 [2.89; 5.27]). When divided by median BMI (29.7&#x2009;kg/m2), AUCGIR,0-60min was significantly higher with AT278-U500 in both the low-BMI and high-BMI subgroup compared to InsAsp-U100. Linear regression showed a significant inverse relationship between BMI and AUCGIR,0-60min for InsAsp-U100 (slope -0.142, p&#x2009;<&#x2009;0.0001), whereas AT278-U500 showed no such relationship. Overall insulin exposure was similar for AT278-U500 and InsAsp-U100, while overall glucose-lowering effect was comparable across all three treatments. CONCLUSIONS: AT278-U500 maintains its ultra-rapid onset characteristics independent of BMI, representing the first ultra-rapid U500 option for prandial dosing in insulin-resistant people with type 2 diabetes requiring high-dose therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05754424.

Humans

Engineering bubble structures as Cas12a activators for highly sensitive monitoring of WRN helicase function.

The Werner syndrome helicase (WRN) is a critical synthetic lethal target in microsatellite instability cancers, essential for resolving complex genomic structures like replication bubbles and R-loops. However, strategies to simultaneously discriminate WRN activity on DNA versus DNA-RNA substrates in living cells are lacking. Here, we developed a structure-specific CRISPR/Cas12a biosensing strategy to visualize WRN functional activity by engineering bubble-structure probes. These probes were rationally designed to structurally mimic DNA replication bubbles and R-loop associated DNA-RNA hybrids. Upon specific unwinding by WRN, the probes release a sequestered activator strand that triggers Cas12a trans-cleavage, effectively converting the unwinding event into an amplified fluorescent signal. This assay achieves low picomolar sensitivity (LODs: 5.6-6.0 pM) and exceptional selectivity against homologous RecQ helicases. Uniquely, this strategy enables the parallel quantification of WRN activity on both substrate types, providing insights into distinct WRN-mediated pathways for resolving genomic stress. We further demonstrated the strategy's utility by visualizing endogenous WRN dynamics in living cells and profiling the efficacy of small-molecule inhibitors. This work offers a powerful molecular toolkit for dissecting WRN biology and facilitating high-throughput drug screening in targeted cancer therapy.

Werner Syndrome Helicase

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