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Should we consider excessive weights in pediatric kidney transplant recepient candidates?: A systematic review and meta-analysis of kidney transplantation outcomes.

INTRODUCTION: In adult populations, excess body weight has been associated with an increased risk of adverse clinical outcomes and mortality following kidney transplantation. In contrast, the influence of obesity on transplantation outcomes among pediatric populations is not yet fully understood. This study aimed to evaluate the association between pre-transplant excess weight and post-transplant outcomes in pediatric kidney transplant recipients. MATERIAL & METHODS: A systematic literature search was performed across PubMed, ScienceDirect, and the Cochrane Library, covering publications up to December 31, 2025. The quality of the included studies was evaluated using the ROBINS-E tool. Statistical analysis was conducted using Review Manager version 5.4. RESULTS: From a total of 1465 records screened, six studies that included 65,483 participants were selected in the meta-analysis. The results indicated that pre-transplant excess weight was significantly associated with an increased risk of acute rejection (OR = 1.09; P = 0.009), delayed graft function (OR = 1.17; P < 0.00001), 1-year graft failure (OR = 1.16; P = 0.0002), and 5-year graft failure (OR = 1.13; P = 0.009). Although 5-year mortality was also higher among recipients with excess weight, this association was not statistically significant (OR = 1.08; P = 0.11). CONCLUSION: Pediatric patients with pre-transplant excess weight had higher post-transplant odds of acute rejection, delayed graft function, and both 1-year and 5-year graft failure compared to those without excess weight. These findings highlight the importance of assessing and managing excess weight prior to kidney transplantation to help prevent adverse outcomes in the future.

Humans

Marginal fit and five-year outcomes of posterior monolithic zirconia restorations: A randomized paired and observational clinical study.

OBJECTIVES: The aim of this study was to evaluate the marginal fit and five-year clinical performance of posterior 5 mol% yttria-partially stabilized zirconia restorations. A randomized paired comparison with lithium disilicate crowns was performed for marginal fit. METHODS: A total of 65 posterior restorations were placed in 38 patients, including 32 zirconia crowns, 17 lithium disilicate crowns, and 16 zirconia partial coverage restorations. In the randomized paired comparison, 17 patients received one lithium disilicate crown and one zirconia crown. Additional zirconia crowns (n=15) and zirconia partial coverage restorations (n=16) were included in a prospective observational cohort. The primary outcome was marginal fit within the randomized cohort. Marginal and internal fit were assessed using the replica technique. Marginal and internal gap values were compared using the Wilcoxon signed-rank test; clinical outcomes were analyzed descriptively, and Kaplan-Meier estimates were calculated for survival and complication-free survival. Clinical performance was assessed using CDA criteria, periodontal parameters, complication recording, and patient-reported outcomes. Clinical examinations were performed at baseline and at 12, 24, 36, 48, and 60 months. RESULTS: Mean marginal gap values at the crown margin were 46 &#xb1;33 &#xb5;m for lithium disilicate crowns and 50 &#xb1;32 &#xb5;m for zirconia crowns (p>0.05). No restoration required replacement, resulting in 100% restoration survival after a median follow-up of 60 months (range: 57-64 months). Most complications were biological or functional, including endodontic, periodontal, occlusal, and proximal-contact-related events. One zirconia partial coverage restoration exhibited a small ceramic fracture managed by polishing. The Kaplan-Meier probability of complication-free survival was 76.4% for zirconia crowns, 66.7% for lithium disilicate crowns, and 87.5% for zirconia partial coverage restorations. CONCLUSIONS: In the randomized paired comparison, 5 mol% yttria-partially stabilized zirconia crowns showed marginal gap values similar to lithium disilicate crowns. All restorations remained in situ during the observation period. Lower complication-free survival was mainly related to biological and functional events and should be interpreted separately from restoration survival. CLINICAL SIGNIFICANCE: Clinical evidence for posterior 5 mol% yttria-partially stabilized zirconia restorations remains limited. This study provides mid-term clinical data on crowns and partial coverage restorations. In the randomized full-crown comparison, marginal fit was similar to that of lithium disilicate crowns, supporting the clinical consideration of monolithic zirconia restorations for posterior teeth.

Humans

Clinical outcomes of zirconia dental restorations: A systematic review and meta-analysis.

OBJECTIVES: To evaluate the survival and success rates of zirconia dental restorations (ZDRs) and their complications. DATA & SOURCES: Electronic searches of PubMed, Cochrane, Embase and Web of Science were conducted up to January 1, 2026. Clinical studies with at least 1-year follow-up evaluating zirconia dental restorations in natural teeth were included. Survival rates, success rates, and biological and mechanical complications were analyzed. Risk of bias was assessed using RoB 2, Newcastle-Ottawa Scale (NOS), and Joanna Briggs Institute tools (JBI). Certainty of evidence was evaluated using the GRADE approach. STUDY SELECTION & RESULTS: Sixty-six studies published between 2008 and 2025 were included. Pooled survival rates ranged from 92.9% to 98.7% up to 10 years for single crowns (SCs), 77.6% over 10 to 13 years for fixed dental prostheses (FPDs), 97.4% for resin-bonded FPDs (RBFPDs) over 10 to 15 years, from 50.0% to 52.6% over 9 to 13 years for conventional cantilever FPDs (CFPDs) and 89.0% for inlay-retained FPDs (IRFPDs) over 10 years. Pooled success rates were 46.1% for SCs over 10 years, 40.1% for FDPs over 10 to 13 years, 84.3% for RBDPDs over 10 to 15 years, 12.5% to 22.6% for CFPDs over 9 to 13 years and 70.3% for IRFPDs over 10 years. Biological and mechanical complication rates were 12.1% and 53.9% for SCs at 10 years, 19.4% and 46.7% for FPDs over 10 to 13 years, 50.0% and 37.5% for CFPDs at 9 years, 21.4% and 14.3% for IRFPDs at 3 years, and 3.3% and 8.0% for RBFPDs over 10 to 15 years. Restorations treated with airborne-particle abrasion (APA) combined with 10-methacryloyloxydecyl dihydrogen phosphate (MDP) achieved favorable short-term clinical outcomes, with pooled survival and success rates of 98.6% and 97.7% for SCs, and 98.1% and 70.1% for IRFPDs, respectively. The included studies were assessed as having low to moderate risk of bias using RoB 2, NOS, and JBI tools, but GRADE assessment yielded evidence of very low certainty. CONCLUSIONS: ZDRs generally demonstrated acceptable to excellent short- to long-term survival and success outcomes. Mid- to long-term clinical performance was varied according to restoration types. The RBFPDs had relatively low complication rates, followed by the SCs, the FPDs and the IRFPDs. CFPDs exhibited relatively low success rates and high complication rates. The predominant biological complications were secondary caries and pulpitis or apical periodontitis, while chipping and debonding were the most common mechanical complications. APA treatment followed by application of MDP is capable of producing favorable short-term clinical outcomes. CLINICAL SIGNIFICANCE: ZDRs except for CFPDs could achieve favorable mid- to long-term clinical performance. CFPDs should be conducted with caution.

Zirconium

A systematic review and meta-analysis of OCT-based ophthalmic changes in amyotrophic lateral sclerosis.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease marked by motor decline and respiratory failure. Optical coherence tomography (OCT), a non-invasive imaging technique, has been explored for detecting retinal structural changes that may reflect neurodegeneration in ALS. While some studies report thinning of retinal layers, findings remain inconsistent. Therefore, a meta-analysis is needed to clarify the extent of retinal involvement and the potential of OCT as a biomarker in ALS. METHODS: A systematic literature search was conducted across PubMed, EMBASE, and Cochrane databases for studies published between 2010 and May 2025. Study quality was assessed using the Newcastle-Ottawa Scale (NOS), and publication bias was evaluated through funnel plot asymmetry and Egger's test. Pooled effect sizes were calculated using random-effects models to account for between-study heterogeneity, and differences in OCT parameters between ALS patients and healthy controls were expressed as standardized mean differences (SMD) with 95% confidence intervals (CI). Statistical heterogeneity was quantified using the I2 statistic. RESULTS: A total of 17 studies were included in the present meta-analysis. The primary unadjusted global model demonstrated significant reduction of retinal nerve fibre layer (RNFL) thickness in ALS patients compared to controls (unadjusted SMD&#xa0;=&#xa0;-0.295, 95% CI: -0.522, -0.068). Upon applying a Design Effect variance inflation model to address fellow-eye non-independence, the pooled estimate remained robustly significant across a conservative range of intraclass correlations (SMD ranged from -0.256 to -0.249). Subgroup analyses revealed that RNFL thinning was particularly pronounced in spinal-onset ALS (SMD&#xa0;=&#xa0;-0.54, 95% CI: (-0.98, -0.10). When studies were stratified by the region of conduct, RNFL and macular thinning reached statistical significance only within the non-Asian subgroup, though the formal test for subgroup differences was not significant. CONCLUSION: This meta-analysis demonstrates significant bilateral RNFL thinning in ALS, with relative preservation of the Inner Nuclear Layer and Ganglion Cell Layer - Inner Plexiform Layer, supporting retinal neurodegeneration as a feature of this multisystem disorder. SYSTEMATIC REVIEW REGISTRATION: PROSPERO identifier CRD420251076035.

Humans

Genetic mutations driving ciprofloxacin resistance in laboratory-evolved Salmonella Typhimurium.

Ciprofloxacin resistance in Salmonella Typhimurium is a significant public health concern, and the mechanisms by which the resistance evolves are poorly defined. Here, by serial passaging under antibiotic selection, we isolated ciprofloxacin-resistant S. Typhimurium mutants and subjected them to whole-genome sequencing to reveal the major mutations associated with resistance. The Low CipR mutant acquired four chromosomal mutations in ramR, icdA, lipB, and gyrA, and the High CipR mutant gained additional mutations in gyrB, yaiC, and corA. Functional characterization determined that mutations in ramR resulted in efflux pump upregulation, while disruptions in the TCA cycle caused by mutations in icdA and lipB led to metabolic alterations. These changes indirectly enhanced resistance by increasing the expression of the global regulator MarA and reducing OmpF-dependent membrane permeability. Despite the observation of the G105A substitution in GyrA, enzymatic assays confirmed the failure to support resistance to ciprofloxacin, possibly because the structural alteration remained minimal. GyrB488-489dup was associated with maintained supercoiling under ciprofloxacin and enhanced fluoroquinolone resistance, suggesting a major role in resistance evolution. Other mutations in yaiC impaired biofilm and, in corA, intracellular accumulation of magnesium, possibly stabilizing the bacterial cell envelope under antibiotic pressure. The findings provide novel explanations for the multifaceted mechanisms leading to ciprofloxacin resistance in Salmonella and suggest targets to combat antimicrobial resistance.IMPORTANCEAntibiotic resistance in Salmonella Typhimurium is an increasing public health concern, yet the genetic changes that allow bacteria to become resistant are not fully understood. In this study, we evolved ciprofloxacin-resistant Salmonella in the laboratory and identified the mutations that arise during resistance development. We found that resistance does not result from a single change but from multiple adaptations affecting drug efflux, metabolism, and the antibiotic target. Some mutations increased the activity of pumps that remove antibiotics from the cell, while others altered bacterial metabolism and reduced membrane permeability, making it harder for the drug to enter. A duplication in the DNA gyrase subunit GyrB played a particularly important role in maintaining DNA function under antibiotic stress. Together, these results reveal how diverse genetic changes cooperate to generate ciprofloxacin resistance and provide insights that may help guide strategies to combat drug-resistant Salmonella infections.

DNA gyrase

The effect of zalunfiban on high sensitivity cardiac troponin and the association with clinical outcomes in patients with STEMI.

BACKGROUND: Among individuals with ST-segment elevation myocardial infarction (STEMI), a single subcutaneous injection of the short-acting glycoprotein IIb/IIIa receptor blocker antagonist zalunfiban at first medical contact significantly improved the primary outcome including clinical endpoints. The impact of zalunfiban on Myocardial Infarction (MI) size and association with downstream outcomes remains unclear. METHODS: In a prespecified analysis, we studied results among study participants treated with 2 doses of zalunfiban who had core laboratory measurements concentrations of hs-cTnT. RESULTS: More elevated hs-cTnT concentrations at presentation were associated with less resolution of ST deviation (P = .006) and more frequent Q wave development (P < .001). At coronary angiography more elevated hs-cTnT at presentation was associated with higher thrombus grade and worse epicardial and myocardial perfusion (all P < .05). In multivariable analyses, higher hs-cTnT concentrations at 24 hours were associated with greater adjusted risk for all-cause death (odds ratio [OR] 1.83 per log unit increase; P = .03), cardiovascular death (OR 1.83 per log unit increase; P = .03), heart failure (OR 2.74 per log unit increase; P < .001) or the composite of death and heart failure (P < .001) by 30 days. At 24 hours, those treated with zalunfiban had lower hs-cTnT compared to placebo (P = .04) and across multiples &#x2265; 10 to &#x2265; 1,000 times elevation, treatment with zalunfiban resulted in smaller hs-cTnT determined MI size. CONCLUSIONS: Among patients with STEMI, more elevated concentrations of hs-cTnT are associated with worse measures of reperfusion and higher-risk for short-term death or heart failure. A single dose of zalunfiban at first medical contact reduced MI size. TRIAL REGISTRATION: A phase 3 study of zalunfiban in subjects with ST-elevation MI (CELEBRATE); NCT04825743.

Humans

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

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

Humans

Experiences of stigma, bias, and communication challenges among pregnant healthcare workers: A systematic review of qualitative evidence.

BACKGROUND: Healthcare work environments are fraught with occupational hazards that can impact pregnant healthcare workers' health as well as patient care. Despite the feminization of healthcare globally, systematic discrimination against pregnant workers persists across diverse healthcare settings and cultural contexts. The intersection of stigma, bias, and communication challenges creates substantial barriers to career advancement and wellbeing. However, no systematic review has synthesized qualitative evidence on how these three constructs interact across healthcare professions and cultural contexts using an integrated theoretical framework. OBJECTIVE: To systematically review and synthesize qualitative evidence on experiences of stigma, bias, and communication challenges among pregnant healthcare workers across different healthcare settings and cultural contexts using an integrated theoretical framework. DESIGN: Systematic review of qualitative studies following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with thematic synthesis. DATA SOURCES: Seven databases were searched from inception to January 2026. REVIEW METHODS: Included qualitative studies were appraised using the Critical Appraisal Skills Programme (CASP) checklist and synthesized through theory-guided thematic synthesis. Confidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation-Confidence in the Evidence from Reviews of Qualitative research (GRADE-CERQual) approach. RESULTS: Fourteen studies encompassing 1223 participants across 17 countries revealed four major themes: (1) professional identity stigma and workplace discrimination through systematic labeling and stereotyping; (2) gender-based institutional bias rooted in masculine organizational logic; (3) multilevel communication failures creating fear-based climates; and (4) individual and collective resistance strategies developed despite constraints. Occupational hazards specific to pregnancy included exposure to infectious diseases, imaging, physical tasks, cleaning products, patient violence, and medication administration. Support from coworkers and supervisors was identified as the most critical facilitator for avoiding hazards and making necessary modifications, while the desire to be 'supernurses' and fear of consequences emerged as significant barriers. These patterns were consistent across healthcare professions, settings, and cultural contexts, with specialty culture and healthcare system type moderating discrimination intensity. Confidence in core findings was rated high using GRADE-CERQual. CONCLUSIONS: Pregnant healthcare workers globally experience interconnected stigma, bias, and communication challenges that are systematically embedded within healthcare organizational structures. These challenges operate synergistically, requiring comprehensive multilevel interventions beyond policy compliance. Healthcare organizations must implement evidence-based strategies addressing stigma reduction, bias interruption, and communication transformation simultaneously to retain skilled workers and ensure quality patient care.

Female

Open repairs with biceps rerouting does not impact retears in large to massive rotator cuff tears compared to conventional open repair: a randomized clinical trial.

BACKGROUND: The treatment of large to massive rotator cuff tears leads to a high failure rate and several techniques have been proposed to improve these results. Rerouting the long head of the biceps tendon (LHBT) appears to be a biological reinforcement to increase tendon healing. Therefore, this study aimed to compare the clinical and radiological outcomes of open repair for large and massive rotator cuff tears reinforced with the LHBT to conventional open repair. METHODS: A prospective randomized study was conducted with patients diagnosed with large to massive rotator posterosuperior rotator cuff tear and intact LHBT, randomized into 2 groups: biceps rerouting and conventional open repair. The functional outcomes were assessed by the American Shoulder and Elbow Surgeon score, University of California at Los Angeles score, and SF-12 questionnaire preoperatively and at 6, 12, and 24 months postoperatively. Pain level was also assessed by the visual analog scale including the first day and 2 weeks postoperatively. Structural outcomes were rotator cuff and LHBT healing with magnetic resonance imaging and acromiohumeral distance (AHD) through radiography. RESULTS: We evaluated 58 patients, 29 in each group. At the end of the follow-up there were no statistically significant differences between groups in American Shoulder and Elbow Surgeon (76.1 vs. 80.4, P = .761), University of California at Los Angeles (27.1 vs. 29.1, P = .634), or visual analog scale scores (1.3 vs. 1.1, P = .781). Additionally, rotator cuff healing rates (48.3% vs. 44.8%, P = .402) and LHBT healing rates (79.3% vs. 82.7%, P = .738) were similar. AHD increased in both groups, with no significant difference in delta AHD (P = .513). Both groups showed significant clinical improvement over time in all evaluated outcomes (P < 0,01). No postoperative complications were reported. CONCLUSIONS: We could not identify an advantage of open repair with LHBT rerouting as reinforcement over conventional open repair. Nonetheless, all clinical scores improved at the end of the 24 months of follow-up in both groups.

Humans

Epigenetic Gene Networks Governing Immune State Transitions Across the Lifespan.

Immune function across development, tissue repair, aging, and disease depends not only on signaling pathways but also on epigenetic architectures that determine whether coordinated transcriptional programs can be accessed and resolved. Increasing evidence indicates that epigenetic gene networks regulate the accessibility and reversibility of semi-stable immune states, shaping plastic, homeostatic, reparative, and degenerative configurations. We propose the concept of epigenetic transition windows, defined as temporally and contextually restricted intervals during which epigenetic constraints are relaxed, permitting coordinated and reversible transitions between immune states. During development, these windows are broad and support immune tolerance and adaptive plasticity. In adulthood they become spatially and temporally restricted, preserving stability while enabling conditional adaptation. With aging, they progressively narrow, contributing to chronic inflammation, impaired repair, and increased vulnerability to neurodegeneration. Conversely, pathological persistence of regulatory permissiveness may underlie immune evasion and sustained plasticity in cancer. We outline operational genomic readouts for quantifying transition windows, including chromatin accessibility variance, enhancer switching dynamics, reversibility metrics, and cross-cell coordination indices, and derive experimentally testable predictions that distinguish this model from pathway-centric or damage-centric explanations. By reframing immune dysfunction as a failure of regulated state transition rather than excessive signaling alone, this framework integrates inflammaging, trained immunity, immune resolution failure, and tumor immune escape within a unified regulatory architecture and provides a systems-level perspective on immune adaptability across the lifespan.

Epigenesis, Genetic

Improving survival in Duchenne muscular dystrophy across eras: a systematic review and cumulative meta-analysis.

BACKGROUND: Duchenne muscular dystrophy (DMD) was historically associated with death in the late teens or early twenties, mainly from respiratory failure. Survival has improved substantially with home mechanical ventilation (HMV) and multidisciplinary care, although variability remains. This study evaluated temporal trends in survival in DMD and the impact of HMV. METHODS: A study-level cumulative meta-analysis (PROSPERO CRD420251163011) of studies reporting survival outcomes in patients with DMD was conducted (PubMed 1977 to 13 October 2025). Pooled estimates of median survival were calculated, and random-effects meta-analyses with predefined subgroups (HMV and study period) were performed, alongside meta-regressions. Risk of bias was assessed using the Newcastle-Ottawa Scale. RESULTS: 53 studies (median follow-up 8&#xa0;years), comprising more than 13,000 patients, of whom 60% received HMV, were included. Median survival differed substantially between ventilated (29&#xa0;years, 95%CI 27 to 31) and non-ventilated (19&#xa0;years, 95%CI 18 to 20) patients. Survival improved progressively over time in both groups. Glucocorticoid therapy was not associated with improved survival (p=0.45), whereas treatment with heart failure medications, including renin-angiotensin system inhibitors (p=0.002) and &#x3b2;-blockers (p=0.02), was associated with longer survival. The predominance of mortality shifted from respiratory to cardiac causes, while enhanced cardiac management was associated with a growing contribution of other causes of death. CONCLUSION: Survival in DMD has increased substantially over time, with median survival now approaching the third decade of life among ventilated patients. The growing contribution of cardiac and other non-respiratory causes of death highlights the importance of long-term multidisciplinary and early cardioprotective intervention. STUDY REGISTRATION: The meta-analysis and systematic review have been registered on PROSPERO (CRD420251163011).

Humans

Wounds that echo: community perceptions of the socio-structural determinants of community violence in post-apartheid South Africa in the context of COVID-19.

The COVID-19 pandemic and its associated public health measures significantly altered the social, economic, and psychological landscape of communities worldwide. In South Africa, the post-COVID-19 period has been marked by a notable surge in homicide rates and interpersonal and community violence. Using a combined structural and social disorganisation framework, this qualitative study critically explores community members' perceptions of the socio-structural factors contributing to community violence, in the context of COVID-19. Utilising data from in-depth interviews and focus group discussions, this study examines the lived experiences of residents in a marginalised high-risk South African community, unpacking the interplay between structural inequities, social disintegration, and community violence. Community violence emerged not as periodic or individual, but as structurally generated, geographically concentrated, and socially normalised. The findings demonstrate that community violence is perceived as being embedded in cycles of survival, where long-standing systemic inequality, economic precarity, spatial disadvantage, and institutional neglect and inequity generate contexts in which community violence becomes normalised and self-reinforcing. The study findings advocate for interventions that not only address immediate catalysts of violence but also the deeper historical and structural determinants of violence in the post-pandemic era, while ensuring preparedness for effective violence prevention during future pandemics.

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

Understanding specificity in immune-brain pathways: A systematic review of differential associations between individual cytokines and brain structure and function measured through magnetic resonance imaging in humans.

Research shows that cytokines are associated with psychiatric disorders, including major depression, and multiple aspects of brain structure and function. Accumulating data suggest that different cytokines may have unique profiles of biological activity, particularly in their neuromodulatory roles, but it is currently unclear whether they have unique associations with specific neural circuits in humans. In this paper, we systematically review magnetic resonance imaging studies conducted with depressed or healthy control human participants under age 65 that examine associations between peripheral cytokines and brain structure and function, with the goal of evaluating evidence for the specificity of these cytokine-brain associations. We find that across multiple measures of brain structure and function, the majority of studies reviewed reported unique associations between individual cytokines and brain outcomes. A synthesis of findings across studies also suggests a preliminary hypothesis of specific associations of interleukin-6 levels in circulation with the default mode network and tumor necrosis factor-alpha with the salience network, which could be tested in future research. We conclude the review with future directions for research that can strengthen understanding of these associations.

Humans

O'nyong-nyong virus adaptive mutations in non-structural protein 1 and 3 enhance RNA replication and overcome FHL1 requirement.

Arthritogenic alphaviruses, like o'nyong-nyong virus (ONNV), cause debilitating musculoskeletal diseases and are geographically expanding. To predict their emergence, we seek to better understand evolutionary mechanisms that enable changes in virus tropism. Here, we identify adaptive mutations in the ONNV non-structural proteins (nsPs) that arose during cellular serial passaging and enabled ONNV to infect non-permissive Lunet cells. Using shotgun proteomics, we show that this human hepatoma cell line lacks the four-and-a-half-LIM domain protein 1 (FHL1), an essential host factor in ONNV RNA replication. Individual single nucleotide mutations in the nsP1 ring-aperture membrane-binding and oligomerization domain, the nsP3 macrodomain, and the nsP3 opal stop codon overcome FHL1 deficiency in Lunet cells by enhanced RNA replication. These findings demonstrate how subtle genomic changes in nsPs can profoundly influence alphavirus replication and tropism.

LIM Domain Proteins

Mesenchymal Stem Cell-Derived Exosomes Combined With 3-Dimensional Hyaluronan-Based Scaffold Promote Tendon-to-Bone Tunnel Healing.

PURPOSE: Tendon-to-bone healing remains a major clinical challenge due to poor regenerative capacity at the enthesis. This study aimed to evaluate the effects of mesenchymal stem cell-derived exosomes combined with a 3-dimensional hyaluronan-based scaffold on graft healing within bone tunnels. This study was conducted in accordance with the ARRIVE (Animal Research: Reporting of In Vivo Experiments) guidelines. METHODS: A total of 128 tendon-bone models were created in 64 Sprague-Dawley rats, randomized into four groups: control, exosome-only, scaffold-only, and exosome-loaded scaffold. At weeks 4 and 8 postoperatively, samples were analyzed histologically (hematoxylin-eosin, Masson Trichrome), immunohistochemically (fibroblast growth factor 2, bone morphogenetic protein 2), and biomechanically (maximum failure load). RESULTS: At both time points, the exosome-loaded scaffold group demonstrated significantly enhanced vascularization, cellular activity, and collagen fiber continuity and parallelism compared to all other groups (P < .05). Fibroblast growth factor 2 and bone morphogenetic protein 2 expression levels were highest in the exosome-loaded scaffold group, indicating early activation of proregenerative pathways. Biomechanically, this group also exhibited the greatest maximum failure load (15.64 &#xb1; 0.86 N at week 4; 22.97 &#xb1; 2.86 N at week 8), suggesting superior tendon-to-bone integration. The exosome-only group showed delayed but comparable improvements by week 8. CONCLUSIONS: Combining mesenchymal stem cell-derived exosomes with a 3-dimensional hyaluronan-based polycaprolactone/tricalcium phosphate scaffold enhances early and sustained healing at the tendon-bone interface. This cell-free, biocompatible strategy significantly improves vascularization, growth factor expression, collagen organization, and mechanical strength. These findings support its potential as a clinically translatable approach for improving tendon-to-bone healing outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Animals

Targeting SIRT6: the design and therapeutic implications of activators and inhibitors.

Sirtuin 6 (SIRT6) is an NAD+-dependent deacylase that maintains genomic stability, regulates metabolism, and influences aging, making it an attractive but challenging therapeutic target. Pharmacological modulation of SIRT6 holds promise for cancer and metabolic disorders, yet its context-dependent functions demand precise intervention strategies. Potent, selective, and drug-like chemical probes are therefore essential to dissect SIRT6 biology and to validate its therapeutic potential. This review critically evaluates recent medicinal chemistry advances in SIRT6 modulation. We focus on structure-guided design strategies and structure-activity relationships (SAR) that have transformed initial hits into optimized leads for both activators and inhibitors, highlighting the remaining challenges in achieving isoform selectivity and drug-like properties.

Sirtuins

Effects of strength and balance training on the structure of the aging brain.

BACKGROUND: While it is established that motor training induces structural changes in the brains of young adults, structural adaptations in aging brains are less studied. METHODS: This randomized controlled study investigated the impact of long-term strength and balance training on the structural plasticity in 60 elderly adults (64 - 82 years old, 70.6 &#xb1; 4.7) using multi-modal neuroimaging. We compared the effects of three months of strength training to balance training of the same duration and to a passive control group. Voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) were used to assess grey matter (GM) and white matter (WM) plasticity. White matter tract integrity (WMTI) modelling was employed to explore the microstructural underpinnings of white matter alterations. RESULTS: We found that strength training was associated with changes in diffusion metrics consistent with white matter microstructural remodeling, specifically increased extra-axonal axial diffusivity in the bilateral inferior fronto-occipital and longitudinal fasciculi. Additionally, both balance and strength training mitigated reductions in axonal water fraction in the splenium of the corpus callosum and the right posterior corona radiata observed in the control group. CONCLUSION: These results underscore the potential relevance of strength and balance training to induce beneficial neural plasticity by counteracting aging-related demyelination in the corpus callosum and highlight the specific role of strength training in facilitating white matter reorganization in key transmission fiber pathways.

Humans