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PubMed2026

Efficacy and Safety of the C3 Inhibitor Pegcetacoplan in Paroxysmal Nocturnal Hemoglobinuria: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the efficacy and safety of the complement C3 inhibitor pegcetacoplan in patients with paroxysmal nocturnal hemoglobinuria (PNH). METHODS: PubMed, Embase, Web of Science, and Cochrane Library were systematically searched for studies reporting pegcetacoplan use in PNH. Outcomes included transfusion-requirement, hemoglobin normalization, mean hemoglobin levels, lactate dehydrogenase normalization, reticulocyte count normalization, and safety endpoints. Pooled proportions with 95% confidence intervals were calculated using random-effects models, and heterogeneity was assessed using the I2 statistic. RESULTS: Five studies comprising 271 patients were included. Transfusion avoidance was observed in 80.6% of patients, with a pooled transfusion-requirement rate of 19.4%. LDH normalization occurred in 68.5% of patients (I2 = 0%). Hemoglobin normalization was observed in 42.9%, while reticulocyte count normalization reached 66%. Any-grade adverse events occurred in 83.5% of patients, most commonly pyrexia, headache, and dizziness. Serious adverse events occurred in 16.6%, decreasing to 12% after sensitivity analysis. Breakthrough hemolysis was reported in 14.8%, and infections in 17%. CONCLUSION: Pegcetacoplan demonstrates consistent efficacy signals across key hematologic endpoints and an acceptable safety profile, supporting its potential role as an important therapeutic option, particularly in patients with persistent extravascular hemolysis despite C5 inhibition.

Humans↗

PubMed2026

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↗

PubMed2026

The utility of 18F-fluorodeoxyglucose PET/computed tomography in relapsing polychondritis: a systematic review and meta-analysis.

Relapsing polychondritis is a rare chronic autoimmune inflammation of the cartilage associated with life-threatening respiratory complications. Currently, no clear role of imaging modalities such as 18F-fluorodeoxyglucose (FDG) PET/computed tomography (CT) is defined in the literature. This systematic review and meta-analysis provide current evidence on the PET-positivity rate and utility in relapsing polychondritis. Prospective or retrospective studies with more than five patients of suspected relapsing polychondritis who underwent 18F-FDG PET/CT during their management and reported a PET-positivity rate were included. Low-sample-size studies describing chondritis due to other aetiologies or utilizing PET-based radiopharmaceuticals other than FDG were excluded. A systematic search using relevant keywords was conducted across four databases (PubMed, Embase, Scopus and Web of Science) to include studies up to 25 April 2025. The Joanna Briggs Institute critical appraisal tools were used for risk-of-bias analysis. Data were analysed using the R software package (v4.3.1; 2023). Out of 962 articles, three with a total of 97 patients were included. With a pooled PET-positivity rate of 94% [95% confidence interval (CI): 73-99%, I2 = 0%, P = 0.76] and a pooled baseline SUVmax of 4.0 (95% CI: 3.5-4.6, I2 = 32%, P = 0.23), 18F-FDG PET identified asymptomatic cartilage involvement in more than 25% patients and PET parameters correlated well with inflammatory markers. It had a higher positivity rate for inaccessible sites, such as peripheral airways, and was crucial in treatment monitoring. The pooled PET-positivity rate of 18F-FDG PET in relapsing polychondritis is high but requires prospective large-sample-size studies to explore the diagnostic accuracy and prognostic implications of 18F-FDG PET in relapsing polychondritis.

Polychondritis, Relapsing↗

PubMed2026

Integrated transcriptomic and metabolomic analyses provide new insights into the response of black rockfish (Sebastes schlegelii) larvae to temperature fluctuations.

Sebastes schlegelii usually encounter elevated and fluctuating water temperatures near its upper thermal limit in summer, yet the hepatic responses of larvae to repeated temperature fluctuation regimes remain unclear. To address this question, S. schlegelii larvae were exposed for 8 days to four thermal regimes: constant 18 °C (CT), constant 28 °C (HT), intermittent cooling from 18 to 8 °C followed by recovery to 18 °C (FL), and intermittent warming from 18 to 28 °C followed by recovery to 18 °C (FH). Survival rate was evaluated, and integrated liver transcriptomic and metabolomic analyses were performed. Final survival rates were 96.67% in the CT group, 97.78% in the FL group, and 77.78% in the FH group. Survival rate in the HT group (38.89%) was significantly lower than that in the other three groups (P < 0.05). HTvsCT, FLvsCT, FHvsCT, and FHvsHT comparisons identified 2598, 1207, 622, and 2404 differentially expressed genes and 627, 606, 690, and 610 differential metabolites, respectively. KEGG enrichment analyses of DEGs and SDMs in HTvsCT highlighted HSP-mediated proteostasis, endoplasmic-reticulum protein processing, branched-chain and sulfur amino acid metabolism, glutathione metabolism, and central carbon metabolism, with upregulated hsp90aa1, bckdha, gclc, and pfkp and reduced levels of branched-chain amino acids and methionine. Compared with HT, FH showed attenuated disturbances in proteostasis, amino acid and redox regulation, and central carbon metabolism, together with recovery-associated glycerophospholipid turnover. FL primarily induced polyunsaturated fatty acid (PUFA)-related membrane lipid remodeling. These findings indicate that hepatic responses differed between continuous high-temperature exposure and temperature fluctuations and between fluctuation regimes.

Animals↗

PubMed2026

Microbial signal profiles and organism-level concordance between plasma metagenomic sequencing and blood culture in suspected bloodstream infection.

Plasma metagenomic next-generation sequencing (mNGS) and blood culture detect different components of the microbial signal and frequently produce discordant organism reports. We characterized microbial signal class, report-derived burden, organism-level concordance, and independent clinical attribution in a retrospective, single-center, episode-level cohort. Among 329 episodes with evaluable plasma mNGS reports, 315 had blood culture performed; 232 were mNGS positive/culture negative and 53 were positive by both methods. In the 232 discordant episodes, the recorded routine-care diagnosis classified 124 as bloodstream infection (BSI) and 108 as non-BSI. Nonviral signals were present in 78.2% and 42.6%, respectively (P < 0.001), and median maximum report-derived sequence counts were 98.5 and 11.5 (P < 0.001). Two laboratory physicians then independently reviewed source records using structured criteria while masked to the recorded BSI label and mNGS organism and sequence-count information. Initial agreement for the five-category BSI assessment was 97.6% (Cohen's kappa, 0.960). Within the mNGS-positive/culture-negative subgroup, adjudicated BSI likelihood showed a modest ordinal association with report burden (Spearman rho = 0.190; P = 0.004), while mNGS organisms were considered supported in 1 episode, plausible in 158, unlikely or contaminant in 72, and unresolved in 1. Among 53 dual-positive episodes, 33 (62.3%) shared at least one species, but only 5 (9.4%) had complete species-set concordance. Plasma mNGS and blood culture therefore frequently generated non-equivalent organism sets. Signal class and report burden contributed graded contextual evidence, but organism-level attribution required clinical review and orthogonal microbiology rather than binary positivity alone.

Humans↗

PubMed2026

Cefoxitin versus cefotaxime as empirical treatment of spontaneous bacterial peritonitis in liver cirrhotic patients: randomized controlled clinical trial.

BACKGROUND: Spontaneous bacterial peritonitis (SBP) is a severe complication of cirrhosis requiring immediate empirical antibiotic therapy. Third-generation cephalosporins are the traditional agents of choice; however, increasing clinical failure rates necessitate the evaluation of alternative antibiotics to ensure optimal therapeutic outcomes. The aim was to investigate the efficacy of cefoxitin versus cefotaxime for SBP treatment. METHODS: A randomized clinical trial was conducted on 140 cirrhotic patients with community-acquired SBP at Al-Rajhy Liver University Hospital, Assiut, Egypt. Patients were randomized to receive either cefotaxime (n = 70) or cefoxitin (n = 70), 2 g every 8 h for 5 days. Polymorphonuclear neutrophil (PMN) counts were measured upon admission, on Day 2 and on Day 5. Clinical response rates at Days 2 and 5, development of hepatorenal syndrome, length of stay and mortality were assessed. RESULTS: According to intention-to-treat analysis, clinical response rates at Day 2 were 74.2% in the cefotaxime group and 80% in the cefoxitin group, while at Day 5, they were 71.4% and 74.3%, respectively (P = 0.704). The PMN counts at Days 0, 2 and 5 showed no significant differences between the cefotaxime and cefoxitin groups (P = 0.889, 0.909 and 0.360, respectively). The incidence of hepatorenal syndrome was 7.1% in the cefotaxime group compared with 8.6% in the cefoxitin group (P = 0.753), and mortality was 15.7% and 12.9%, respectively (P = 0.629). CONCLUSIONS: Cefoxitin showed comparable effectiveness to cefotaxime but may be utilized in selected clinically stable SBP patients.

Humans↗

PubMed2026

Interface-dependent V. parahaemolyticus biofilm under varying temperatures, media, and oxygen conditions: implications for seafood safety.

Vibrio parahaemolyticus biofilms play a critical role in pathogen persistence in marine and seafood-processing environments, where oxygen availability, temperature, and surface interfaces vary widely. This study investigated biofilm development by three strains on partially submerged stainless-steel coupons under gas-liquid-wall (GLW) and fully submerged (SM) interfaces. Viable cell counts (log₁₀CFU/cm2) along with normalized protein concentration per viable cell (nProt) and normalized polysaccharide concentration per viable cell (nPol) were measured, under aerobic and anaerobic conditions across a temperature range of 15-30 °C, using tryptic soy broth with 3% NaCl (TSB) and seawater-based medium (SW). GLW biofilms consistently exhibited higher cell counts (6.4-7.3 log₁₀CFU/cm2) compared to SM biofilms (5.9-6.3 log₁₀CFU/cm2), suggesting that enhanced oxygen diffusion promotes bacterial proliferation. Conversely, SM biofilms exhibited significantly higher nProt and nPol levels (p < 0.001), indicating increased production of the extracellular polymeric substance (EPS) matrix under low-oxygen, high-nutrient conditions. Microscopy and three-dimensional surface plot analyses revealed relatively uniform biofilm layers at the GLW interface, whereas SM biofilms formed heterogeneous, tower-like structures. EPS production was further influenced by medium composition, oxygen, and temperature. SM biofilms grown in SW exhibited significantly higher nProt and nPol than those in TSB under aerobic conditions (p < 0.001), indicating enhanced matrix stabilization. Under anaerobic conditions at 15 °C, nProt and nPol were higher, whereas under aerobic conditions, peak nProt and nPol occurred at elevated temperatures. These findings highlight a trade-off between bacterial growth and matrix production and provide insight into biofilm adaptation and persistence in seafood-processing environments. These insights may help develop improved biofilm control and seafood safety management.

Biofilms↗

PubMed2026

Acute Performance, Mechanical and Thermal Effects of Isometric Conditioning Versus Standardized Volleyball Pre-Training Activation in Highly Trained Male Players.

This study compared acute performance, neuromuscular, and thermal responses to a maximal isometric conditioning activity (ICA) versus a standardized volleyball pre-training activation (VPA) in highly trained male volleyball players, and to explore putative mechanisms underpinning post-activation performance enhancement (PAPE) considering training load. In a randomized crossover, 14 men (27 ± 3 y) completed two sessions: VPA (mobility/plyometric drills; 9 min), and ICA comprising 3×5×3-s maximal isometric back-squat contractions (knee angle 120°; 3-min inter-set rest). Countermovement jump (CMJ) height (primary), relative peak power (PP), RSImod, and contraction time (CT) were recorded pre and 3, 6, 9, and 12 min post. Rectus femoris muscle viscoelastic properties and skin surface temperature (SST) were assessed at matched time points. Analyses used repeated-measures ANOVA, responder analysis, correlations, and regression. Period×Sequence interactions favored ICA for CMJ and PP when delivered in Period 2 (lower training volume): ∆CMJ was higher under ICA versus VPA (p = 0.005, d = 1.20); PP likewise greater (p = 0.026, ηp2 = 0.35). ICA yielded more beneficial responders than VPA (9/14 vs 1/14; McNemar exact p = 0.021). In Period 2, reductions in rectus femoris muscle stiffness independently predicted CMJ gains (β_std = -0.495, p = 0.005), whereas SST changes did not (p = 0.974). RSImod and CT showed no differences. A brief, high-effort isometric squat protocol was associated with superior acute improvements in jump performance compared with a standard volleyball warm-up, but this advantage emerged specifically when the preceding training volume was reduced (Period 2), suggesting that residual fatigue from training may reduce the effects of PAPE. Gains align with neuro-mechanical rather than thermal mechanisms, supporting ICA as a practical, equipment-minimal priming strategy for elite volleyball.

Humans↗

PubMed2026

The radiographic effect of cage subsidence on neuroforamina after anterior cervical discectomy and fusion.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: The objective of this study is to investigate the effect of cage subsidence on neuroforaminal area after anterior cervical discectomy and fusion (ACDF) utilizing computed tomography (CT). SUMMARY OF BACKGROUND DATA: Restoration of disc height via implantation of an interbody device provides an indirect decompression of the cervical neuroforamina. Interbody cage subsidence is a potential postoperative occurrence, but the effect of this on neuroforaminal area has yet to be characterized. METHODS: A retrospective review was conducted of patients who underwent one- to four-levels of ACDF utilizing an interbody device with anterior plating. Cage subsidence, neuroforaminal area, height and width were measured on CT scans preoperatively and at least 6 months postoperatively. Levels with a cumulative sum of cranial and caudal subsidence greater than 4 mm were classified as severely subsided, while levels with cumulative subsidence less than 4 mm were classified as non-severely subsided. RESULTS: A total of 83 patients (151 levels) were included in this retrospective analysis. Average endplate subsidence was 3.2 ± 1.9 mm. Non-severely subsided levels demonstrated a greater perioperative increase in neuroforaminal area (7.9 vs 2.1 mm2, p < 0.001), neuroforaminal height (1.1 vs 0.4 mm, p < 0.001) and neuroforaminal width (0.7 vs 0.1 mm, p < 0.001) compared to severely subsided levels. Interbody subsidence significantly predicted a decreased change in neuroforaminal height, width and area (p < 0.001). Severe subsidence was associated with an increased rate of pseudarthrosis, but similar reoperation rates and recurrent neurologic deficits between the two groups. CONCLUSIONS: Severe subsidence of interbody cages after an ACDF was associated with a decreased perioperative change in neuroforaminal dimensions. This decrease in the size of the neuroforamen may reduce the effect of indirect decompression of the nerve root.

Humans↗

PubMed2026

Patient and hospital factors associated with disparities in acute stroke treatment in community and academic hospitals.

BACKGROUND: Systemic barriers may affect identification, emergency transportation (EMS), and care coordination for people with stroke. We assessed patient- and hospital-level factors for associations with pre-hospital and emergency department care. We compared trends for patients presenting to an academic medical center (AMC) versus community hospitals (CHs). METHODS: We conducted a retrospective cohort study at an AMC (Tufts Medical Center) with 542 patients aged ≥18 years hospitalized with acute ischemic stroke or transient ischemic attack between 1/1/2018-12/31/2020 who presented directly to AMC or presented to AMC as a transfer from initial contact CHs. Primary outcomes were EMS use, stroke code activation, door-to-CT time, and door-to-needle time. RESULTS: AMC patients identifying as non-Hispanic Asian (odds ratio (OR) = 0.25; 95% confidence interval (CI) = 0.13-0.47) and Hispanic (OR = 0.19; 95% CI = 0.05-0.72) and CH non-Hispanic Black/African-American patients (OR = 0.17; 95% CI = 0.05-0.62) were less likely to use EMS compared to non-Hispanic white patients. Patients with non-English primary language were less likely to use EMS (OR = 0.38; 95% CI = 0.23-0.63) compared to English-speaking patients in both hospital settings. CH Hispanic patients were less likely to have stroke code activation (OR = 0.24; 95% CI = 0.05-0.86) compared to non-Hispanic white patients. CH patients were less likely to have stroke code activation (OR = 0.12; 95% CI = 0.07-0.19), had 31% shorter door-to-CT time (95% CI = 15-43% shorter), and had 29% longer door-to-needle time (95% CI = 5-58% longer). CONCLUSION: Patient-level factors and hospital setting were associated with differences in acute care suggesting opportunities for community outreach on EMS use, interventions to alleviate language barriers, and a need to address systemic biases.

Humans↗

PubMed2026

Nurse-Led Home-Based Mobile Health Cardiac Rehabilitation Program for Patients With Chronic Heart Failure: A Randomized Controlled Trial.

This 12-week randomized controlled trial evaluated a nurse-led mHealth intervention for patients with chronic heart failure, conceptually informed by Riegel's middle-range theory of self-care of chronic illness. The program integrated wearable activity tracking with weekly nurse-led behavioral coaching, reflecting the core self-care processes of monitoring, maintenance, and management. Compared with usual care, the intervention significantly improved daily step count, 6-minute walk distance, metabolic equivalents, and left ventricular ejection fraction. Findings highlight the effectiveness of theory-informed, nurse-delivered mHealth strategies in enhancing physical activity and cardiopulmonary function, while underscoring the critical role of advanced practice nurses in home-based chronic disease management.

Aged↗

PubMed2026

Ivonescimab plus chemotherapy versus placebo plus chemotherapy in patients with advanced EGFR-mutated non-small-cell lung cancer after disease progression on EGFR tyrosine kinase inhibitor therapy (HARMONi): a multicentre, randomised, double-blind, phase 3 trial.

BACKGROUND: Ivonescimab has shown clinical efficacy in non-small-cell lung cancer (NSCLC). We aimed to assess the efficacy and safety of ivonescimab plus chemotherapy versus placebo plus chemotherapy in patients with advanced EGFR-mutated NSCLC whose disease progressed after third-generation EGFR tyrosine kinase inhibitor (TKI) therapy. METHODS: HARMONi is a randomised, placebo-controlled, double-blind, phase 3 trial done at 114 cancer centres and hospitals across Asia, Europe, and North America. Eligible patients were aged at least 18 years (upper limit: 75 years in Asia) with stage IIIB/IIIC or IV non-squamous EGFR-mutated NSCLC, disease progression after treatment with a third-generation EGFR-TKI, and an Eastern Cooperative Oncology Group performance status score of 0 or 1. Patients were randomly assigned (1:1) via a centralised interactive voice response system or interactive web response system to receive ivonescimab (20 mg/kg) or placebo plus pemetrexed (500 mg/m2) and carboplatin (target area under the curve 5 mg/mL per min) intravenously every 3 weeks. Randomisation was stratified by brain metastases status at enrolment and geographical region. The primary endpoints were progression-free survival by blinded independent radiology review committee and overall survival in the intention-to-treat population. Safety was assessed in patients who received at least one dose of trial treatment. This study is registered with ClinicalTrials.gov (NCT06396065), has completed enrolment, and is ongoing for treatment and follow-up. FINDINGS: From Jan 25, 2022, to Oct 1, 2024, 660 individuals were screened for eligibility; of these, 438 were enrolled and randomly assigned to receive ivonescimab plus chemotherapy or placebo plus chemotherapy (219 per group). Of enrolled patients, 257 (59%) were female and 181 (41%) were male; 306 (70%) reported race as Asian, and 105 (24%) as White. At a median follow-up of 22·3 months (95% CI 21·5-23·0), 275 progression or death events had occurred in 345 patients (129 events among 172 patients in the ivonescimab plus chemotherapy group and 146 events among 173 patients in the placebo plus chemotherapy group). Median progression-free survival was 6·8 months (95% CI 5·7-7·1) in the ivonescimab plus chemotherapy group versus 4·4 months (4·1-5·5) in the placebo plus chemotherapy group (hazard ratio [HR] 0·52; 95% CI 0·41-0·66; p<0·0001). At a median follow-up of 29·7 months (95% CI 27·7-31·0), 262 deaths occurred in 438 patients (122 in the ivonescimab plus chemotherapy group and 140 in the placebo plus chemotherapy group). Median overall survival was 16·8 months (14·3-19·0) in the ivonescimab plus chemotherapy group versus 14·0 months (12·8-15·7) in the placebo plus chemotherapy group (HR 0·79; 0·62-1·01). The most common grade 3-4 treatment-related adverse events in the ivonescimab plus chemotherapy versus the placebo plus chemotherapy group were decreased neutrophil count (42 [19%] of 218 vs 36 [17%] of 218), decreased white blood cell count (28 [13%] vs 24 [11%]), decreased platelet count (27 [12%] vs 14 [6%]), and anaemia (22 [10%] vs 27 [12%]). Serious treatment-related adverse events occurred in 61 (28%) patients in the ivonescimab plus chemotherapy group and 33 (15%) patients in the placebo plus chemotherapy group. Treatment-related adverse events led to death in four patients (disease progression, multiple organ dysfunction syndrome, and hepatic failure, each in one patient; gastrointestinal haemorrhage and pulmonary embolism in one patient) in the ivonescimab plus chemotherapy group and five patients (pneumonitis, myocardial infarction, cerebrovascular accident, cognitive disorder, and embolic stroke, each in one patient) in the placebo plus chemotherapy group. INTERPRETATION: Ivonescimab plus chemotherapy showed a clinically meaningful and statistically significant progression-free survival benefit in patients with EGFR-mutated NSCLC after progression on EGFR-TKI therapy. The clinical benefit and lack of new safety signals of ivonescimab with chemotherapy support the potential for the combination as a new treatment option in this patient population. FUNDING: Summit Therapeutics.

Humans↗

PubMed2026

Wedge tarsectomy using patient specific instrumentation for complex multiplanar foot deformity Reconstruction: A prospective case series.

BACKGROUND: Bony correction in complex cavovarus deformities is often multiplanar. We examine our results following wedge tarsectomy (WT) using patient-specific instrumentation (PSI). METHODS: This single-centre, prospective case series evaluated noncorrectable cavovarus feet undergoing PSI-guided WT. Accuracy of PSI guides/plans, operative duration, and adjunctive procedures were recorded. Weightbearing CT (WBCT) measurements and PROM scores were recorded preoperatively and postoperatively, with 1 year follow-up. Data was then statistically analysed. RESULTS: Eleven patients were included. Planned correction was achieved (two required minor intraoperative adjustments to the initial osteotomy and nine required adjunctive procedures). Mean operative time was 135 min. Postoperative improvements were significant radiologically and in MOxFW walking distance. All fused by 3 months, with no significant complications. CONCLUSION: PSI-guided wedge tarsectomy safely achieves predictable multiplanar corrections. Our unit's experience has been excellent, with improvement in patients' walking, particularly with larger deformity corrections. LEVEL OF EVIDENCE: Level IV, prospective case series.

Humans↗

PubMed2026

Mitochondrial translocation of DNMT3L suppresses oxidative phosphorylation and restrains megakaryopoiesis.

DNMT3L, a catalytically inactive member of the DNA methyltransferase family, is identified here as a negative regulator of megakaryopoiesis. In K562 cells undergoing PMA-induced megakaryocytic differentiation, DNMT3L protein levels declined progressively, and shRNA-mediated depletion enhanced differentiation, whereas overexpression attenuated it. Consistent with these findings, Dnmt3l-knockout mice exhibited elevated peripheral blood platelet counts and expanded bone marrow megakaryocytes. Mechanistically, megakaryocytic differentiation triggered rapid mitochondrial translocation of DNMT3L within 6 h; mitochondrial DNMT3L suppressed oxidative phosphorylation (OXPHOS) capacity and ATP production and downregulated mitochondrial-encoded genes spanning Complex I, III, IV, and ATP synthase, without altering mitochondrial DNA copy number. This metabolic suppression was mediated through compartment-specific remodeling of DNMT3L-containing protein complexes: upon differentiation, DNMT3L selectively dissociated from DNMT1 and DNMT3B in mitochondria, relieving the repressive constraint on OXPHOS, whereas in the nucleus DNMT3L remained associated with DNMT3A, which concomitantly accumulated during differentiation. These findings reveal a previously unrecognized mechanism by which a catalytically inactive epigenetic co-regulator spatially redistributes to coordinate mitochondrial metabolic output with nuclear epigenetic control, thereby facilitating terminal megakaryocytic maturation.

Animals↗

PubMed2026

High levels of mitotic gene conversion are needed to effectively purge deleterious mutations in asexual organisms.

Self-fertilisation and asexual reproduction are both hypothesised to cause long-term extinction due to inefficient selection against deleterious mutations. Self-fertilisation can counter these effects through creating homozygous genotypes and purging deleterious mutations. Although complete asexuality lacks meiotic gene exchange, mitotic gene conversion creates homozygous regions that could limit deleterious mutation accumulation in an analogous manner. We compare mutation accumulation in self-fertilising and facultative sexual populations subject to mitotic gene conversion, and quantify the efficacy of purging in the latter. We first show analytically that purging is most effective with high levels of asexuality and gene conversion, and when deleterious mutations are recessive. We further show using simulations that, when mitotic gene conversion becomes sufficiently high in obligate asexuals, there is a reduction in the mutation count and a jump in homozygosity, reflecting purging. However, this mechanism is not necessarily as efficient at purging under high self-fertilisation, and elevated rates of mitotic gene conversion seem to be needed for widespread purging compared to empirical estimates. If gene conversion rates are allowed to evolve, then elevated rates that increase mean fitness can arise, but only if there is sufficient variance in the gene conversion rate. Conversely, if gene conversion rates are already high and rates are not constrained then they will slightly decrease, reducing mean fitness.

Self-fertilisation↗

PubMed2026

Impaired adaptation to smoke-derived phenolic compounds in Listeria monocytogenes CC204 from smoked salmon and trout.

Listeria monocytogenes is a major foodborne pathogen in ready-to-eat smoked fish products. This study evaluated whether clonal complex affiliation contributes to variability in growth responses to stresses representative of smoked salmon and trout processing. Ten strains were studied, including strains from CC121, CC26 and CC204, the three major clonal complexes reported in the French smoked salmon and trout sectors, together with the EGDe reference strain. Strains were exposed to salt, cold, smoke-derived phenolic compounds and combined stress conditions. Growth responses were compared with whole-genome-based phylogeny, and the impaired phenotype observed under phenolic exposure was further investigated using viable counts, live/dead microscopy and comparative genomics. Growth profiles were partly structured by clonal complex, with strains from the same clonal complex showing similar behaviour across stress conditions. Salt and cold reduced growth globally, while smoke-derived phenolic compounds were the most discriminating conditions. CC204 strains showed markedly lower growth rates under phenolic exposure than CC121, CC26 and EGDe. This phenotype was not associated with loss of cultivability or significant loss of membrane integrity. Comparative genomics did not identify a clear gene-content determinant explaining the CC204 phenotype. These results suggest that CC204 has an impaired adaptive response to smoke-derived compounds, likely involving regulatory or physiological mechanisms.

Listeria monocytogenes↗

PubMed2026

Targeted variant analysis of feline mediastinal lymphoma using MassARRAY and clinical associations.

Lymphoma is the most commonly diagnosed cancer in cats. This study used the Agena MassARRAY to genotype 40 variants across 17 genes in feline mediastinal lymphoma. These variants have previously been identified in tumors, including T- and B-cell lymphomas, acute and chronic lymphocytic leukemias, and mast cell tumors, in humans, dogs, and cats, using various methods. They were selected based on high prevalence reported in prior oncology studies, potential relevance to targeted therapy, and suitability for multiplex PCR amplification. Pleural fluid samples were collected from 76 cats with mediastinal lymphoma, including 69 domestic shorthairs, two Persians, two Siamese, two Wichienmaat, and one Scottish Fold. The most prevalent variants were found in the BCL2, KIT, STAT3, and ZEB1 genes. Specifically, BCL2 c.83275986G > A and c.83275992G > T were present in 71.1% and 57.9%, respectively. In cats with variant-positive in KIT c.163965724C > CT significantly reduced (11 days) compared to wild-type cats (94 days) (p < 0.001). In cats with variant-positive in STAT3 c.42942437C > CA, resulted in shorter median survival compared to wild-type cats (18 days vs. 77 days, p = 0.006). The findings suggest that the variant panel could be useful for the genomic landscape of feline mediastinal lymphoma and warrant further validation.

Animals↗

PubMed2026

Prophylactic folinic acid prevents pemetrexed myelosuppression: A randomized trial toward safer treatment with chemotherapy in non-small cell lung cancer.

Background Pemetrexed is a cornerstone in advanced non-small cell lung cancer treatment. Although generally well tolerated, severe myelosuppression occurs in 26% of patients. Preventing chemotherapy-associated toxicity has become increasingly important with the introduction of osimertinib combined with pemetrexed-based chemotherapy. Due to substantial toxicity, this regimen is often not administered to frail patients. Folinic acid prophylaxis can mitigate pemetrexed-induced toxicity, however its preventive use has not been routinely studied. We aimed to investigate the efficacy of folinic acid prophylaxis to reduce myelosuppression. Methods Fifty patients treated with pemetrexed were randomized (1:1) to receive pemetrexed with or without oral folinic acid prophylaxis on days 2-4 after each chemotherapy cycle. The primary endpoint was absolute neutrophil count (ANC) after the first chemotherapy cycle. Secondary endpoints included ANC after the second cycle, grade neutropenia, treatment efficacy, renal function and incidence of dose modifications. Results Twenty-four patients received folinic acid and twenty-six served as controls. Higher ANC were observed in the folinic acid group after the first cycle (median 3.79; IQR 2.22-4.93 vs. 1.85; IQR 1.43-3.78; p.

Humans↗