Tag: statistics

Mol Imaging Biol. 2026 Feb 23. doi: 10.1007/s11307-026-02084-x. Online ahead of print.

ABSTRACT

PURPOSE: To assess hypoxia-associated host-tumour vascular adaptations and glycolytic metabolism in the chick chorioallantoic membrane (CAM) glioblastoma model.

PROCEDURES: U251 GBM cells were conditioned under normoxia (21% O₂) or hypoxia (1% O₂) for 72 h before implantation onto the CAM on embryonic day 7 (E7). Imaging was performed on E13 using MRI (control-CAM n = 8, normoxic-tumour n = 7, hypoxic-tumour n = 6) and brightfield microscopy (control-CAM n = 7, normoxic-tumour n = 8, hypoxic-tumour n = 7). Tumours were harvested on E14 for histology and gene expression analyses. In a separate cohort of 25 GBM-CAM tumours grown under normoxic conditioning, the correlation of glucose metabolism was assessed using [¹⁸F]FDG-PET on E12 followed by lactate MRS on E13 (n = 8).

RESULTS: Normoxia- and hypoxia-conditioned tumour-bearing CAMs exhibited vascular remodelling and significant upregulation of VEGFA and ADM compared to cultured cells. αSMA staining confirmed vessel infiltration in normoxia-conditioned tumours. CAIX staining revealed a hypoxic core in these tumours while hypoxia-conditioned tumours displayed heterogeneous staining. In both conditions, GLUT1 staining colocalised with CAIX staining, indicating hypoxia-associated glycolysis. GLUT1, PDK1 and LDHA expression was elevated in CAM tumours relative to tumour cells in vitro. In the metabolic imaging cohort, most tumours exhibited [¹⁸F]FDG uptake and lactate signal. However, no statistically significant relationship was observed between the two methods.

CONCLUSIONS: The CAM model provides a versatile platform for investigating GBM vascularisation and metabolism. Hypoxic conditioning amplifies transcriptional and vascular changes to the CAM. Although both [¹⁸F]FDG uptake and lactate were measurable, no significant correlation between the two was observed, potentially reflecting variability in tumour engraftment, vascular delivery of [¹⁸F]FDG, and microenvironmental influences on lactate accumulation.

PMID:41731278 | DOI:10.1007/s11307-026-02084-x

Sports Med. 2026 Feb 23. doi: 10.1007/s40279-026-02395-7. Online ahead of print.

ABSTRACT

BACKGROUND: The literature is equivocal on whether complex training (i.e., combining traditional resistance and ballistic exercises within a single session) is superior to ballistic training in improving physical fitness qualities. This systematic review with meta-analysis aims to compare the effects of complex and ballistic training on physical fitness outcomes.

METHODS: A systematic search using the PRISMA 2020 guidelines was conducted in electronic databases (i.e., PubMed, Scopus, Web of Science). From the included studies, data were extracted for linear sprint, vertical jump (i.e., countermovement jump, squat jump), change of direction speed, and maximal strength. The risk of bias of the included studies was assessed using RoB-2 and ROBINS-I tools for randomized and nonrandomized studies, respectively. The meta-analyses were computed using a DerSimonian and Laird random effects model, reporting Hedges’ g effect size (ES) with 95% confidence and prediction intervals. Statistical significance was set at p ≤ 0.05. In addition, the certainty of evidence was assessed using the GRADE approach.

RESULTS: A total of 20 studies were initially eligible. However, one study was excluded owing to critical concerns at risk of bias assessment stage. Thereafter, 19 studies involving 537 participants ranging from “tier 0” (i.e., sedentary) to “tier 3” (i.e., highly trained) level were included. Randomized studies presented low (k = 2), some (k = 10), and high concerns (k = 5) regarding the risk of bias, while nonrandomized studies presented moderate concerns (k = 2). Compared with ballistic training, significantly greater improvements were reported after complex training for one-repetition maximum (ES = 1.12, p = 0.010), squat jump (ES = 0.37, p = 0.004), 10 m (ES = 0.67, p = 0.033), and 40 m (ES = 0.72, p = 0.005) linear sprint. Furthermore, a significant moderating effect of training duration was observed for complex training, favoring longer (> 7.5 weeks) interventions. The certainty of the evidence was low for the squat jump and very low for all other outcomes.

CONCLUSIONS: Our findings suggest complex training to be superior in improving one-repetition maximum squat, squat jump, 10 m, and 40 m linear sprint compared with ballistic training alone. However, 5 m, 20 m, change of direction speed, countermovement jump, and jump power were similarly improved after both training methods. In addition, a longer intervention duration (> 7.5 weeks) may optimize complex training effects. However, the certainty of the evidence was low for the squat jump and very low for all other outcomes. To increase confidence in the certainty of the current evidence, and therefore to provide robust recommendations favoring (or not) the use of complex training (and its prescription factors) over ballistic training to improve participants’ physical fitness, more robust studies would be required (e.g., larger samples).

PROTOCOL REGISTRATION: The protocol was published in the Open Science Framework (OSF) platform on 13/04/2024 (DOI: https://doi.org/10.17605/OSF.IO/STUZ7 ; Archive link: https://archive.org/details/osf-registrations-stuz7-v1 ).

PMID:41731268 | DOI:10.1007/s40279-026-02395-7

Ann Biomed Eng. 2026 Feb 23. doi: 10.1007/s10439-026-04040-w. Online ahead of print.

ABSTRACT

PURPOSE: Traditional hypertonia diagnosis relies on the Modified Ashworth Scale (MAS), which is subjective and dependent on doctors’ experience. Although previous studies have explored the use of force sensors and surface electromyography (sEMG), finding a reliable and valid detection method remains a challenge. This study aims to develop a simple yet effective platform that integrates biomechanical and sEMG data for upper-limb muscle tone assessment, providing a more objective and quantitative evaluation approach.

METHODS: A detection platform was developed to collect biomechanical and sEMG data from 59 subjects, including 49 patients (MAS Ⅰ = 21, MAS Ⅰ + = 16, MAS Ⅱ = 12) and 10 healthy individuals, at different movement speeds (15°/s, 20°/s, and 25°/s). The acquired data underwent feature extraction, including signal processing and statistical analysis. Dimensionality reduction was applied to optimize the extracted features, and these features were then integrated into a classification algorithm for further analysis.

RESULTS: The extracted features effectively distinguished patients from healthy individuals, with statistically significant differences (p < 0.01). Furthermore, the strong correlation between the extracted features and MAS scores (p < 0.01) confirmed the reliability of the proposed method. Finally, the classification algorithm demonstrated high consistency with clinical evaluations, validating its potential for clinical application in muscle tone assessment.

CONCLUSION: This study introduces an objective and quantitative method for assessing muscle tone, shifting away from the traditional subjective MAS evaluation. By enhancing diagnostic accuracy, the proposed approach provides a more reliable basis for hypertonia diagnosis and treatment. The findings hold significant promise for optimizing clinical decision-making, ultimately improving patient management and therapeutic strategies.

PMID:41731265 | DOI:10.1007/s10439-026-04040-w

J Radiol Prot. 2026 Feb 23. doi: 10.1088/1361-6498/ae490e. Online ahead of print.

ABSTRACT

Borated polyethylene is an effective neutron moderator and absorber in medical linear accelerator shielding; however, there is limited data regarding the required material thickness for adequate neutron attenuation. To address the gap in shielding data, our study systematically quantifies first and equilibrium tenth-value layers (TVL1 and TVLe) for polyethylene containing 0%, 5% and 30% natural boron by weight across neutron energies ranging from thermal to fast. Comprehensive Monte Carlo simulations (n = 3504) were performed to estimate TVL thicknesses from thermal to 20 MeV neutrons. A current tally was used to count neutrons exiting the shield and determine thicknesses corresponding to 10% and 1% transmission. Sixteen energies and 73 thicknesses of materials were modelled with statistical uncertainties below 3%. TVL thicknesses were independently validated with PHITS using identical simulation parameters. We found that TVL values ranged from 1.3 mm for thermal neutrons in borated polyethylene, to 50 cm for 20 MeV neutrons in pure polyethylene. In all cases, adding boron to polyethylene reduced the TVL, with the greatest effect at thermal energies, and a smallest effect at 12 MeV. Here we provide the first comprehensive characterization of borated polyethylene’s ability to attenuate neutrons, supporting shielding design for medical linear accelerators.

PMID:41730243 | DOI:10.1088/1361-6498/ae490e

Am Nat. 2026 Mar;207(3):347-355. doi: 10.1086/738891. Epub 2026 Jan 27.

ABSTRACT

AbstractGenomic forecasting is an emerging area of predictive ecology and evolution that leverages high-throughput sequencing to incorporate information on genomic variation into quantitative predictions of biological responses to environmental change. A central and increasingly applied concept in this field is genomic offset, a measure of the mismatch between current genomic composition and that predicted in new environments. This special issue brings together six studies spanning theoretical and methodological development, empirical evaluation, time series analysis, and conservation applications aimed at advancing the potential of genomic offset and related forecasting approaches for predicting population responses to environmental change. Contributions explore how genomic offset relates to stabilizing selection, compare individual- versus population-level offset models, and evaluate predictions using common garden experiments, long-term forest inventories, genomic time series, and conservation-relevant taxa. Collectively, the articles underscore both the promise and the current limitations of genomic forecasting while emphasizing that model predictive performance is often context dependent and influenced by statistical method, loci choice, and fitness proxies. Future progress will require rigorous validation, theory and methods development, and broader taxonomic coverage to ensure that genomic forecasting can realize its potential for informing biodiversity management in a rapidly changing world.

PMID:41730225 | DOI:10.1086/738891

Am Nat. 2026 Mar;207(3):356-367. doi: 10.1086/739079. Epub 2026 Jan 13.

ABSTRACT

AbstractGenomic offset metrics are increasingly used to predict population maladaptation under changing climates, based on the assumption of a negative statistical relationship between offset measures and local relative fitness. Recent theoretical advances have confirmed this relationship by relating genomic offset to phenotypic trait distances along selection gradients. However, these metrics typically rely on the assumption that stabilizing selection, which maintains local adaptive optima, operates on fitness-related traits through Gaussian-shaped selection gradients. In this study, we extend the theory to accommodate more diverse forms of selection gradients and introduce more general genomic offset measures that preserve the fitness-offset relationship. We validate this generalization through simulations and demonstrate the utility of these new measures in predicting relative fitness in common garden experiments involving three plant species: pearl millet, a vital staple cereal grown in arid soils, and two emblematic North American tree species, balsam poplar and red spruce. Our findings indicate that assuming a local Gaussian-shaped selection gradient for climate adaptation is a robust approximation for these species. These results have important implications for validating genomic offset predictions using fitness proxies and for studies that aim to predict fitness loss based on genomic offset metrics.

PMID:41730221 | DOI:10.1086/739079

JMIR Form Res. 2026 Feb 23;10:e82865. doi: 10.2196/82865.

ABSTRACT

BACKGROUND: In 2017, the US Department of Health and Human Services declared a national opioid crisis. In 2022, an estimated 81,806 overdose deaths involved an opioid. Emergency departments are critical in the pathway of care for providing resources and linkages to services. Studies investigating emergency medicine (EM) physicians’ perspectives on the opioid crisis have largely focused on prescribing.

OBJECTIVES: To investigate EM physicians’ perspectives on response strategies to the opioid crisis of biosurveillance and linkages to care. A secondary objective was to map reported challenges and recommendations using a sequential intercept model as an actionable framework.

METHODS: This is a qualitative study. Six EM physicians in an academic health care system were interviewed through semi-structured interviews. Interviews were transcribed, then thematically coded and analyzed to identify cross-sector settings and barriers to care with corresponding recommendations. Settings and recommendations were mapped as a sequential intercept model.

RESULTS: EM physicians identified 9 key settings as crucial touch points in the opioid crisis: home setting, emergency medical services, patient care, clinically relevant data and information, prescriptions and pain management, predischarge coordination, outpatient resources, biosurveillance sample collection, and the external partner and administrative environment. Biosurveillance challenges included concerns about collecting biological materials for state and regional monitoring, as well as the time burden for sample collection. Linkage to care challenges included social determinants of health and limited outpatient care access. Recommendations were specific to each setting and included care coordination and fostering cross-sector partnerships. A patient-centered approach and better integration of community resources were emphasized.

CONCLUSIONS: The service delivery culture is of acute and episodic care but needs to more seamlessly address care across its fragmented multicomponent complex system. EM physicians face systemic challenges and provide actionable recommendations to promote comprehensive care to patients presenting to the emergency department with opioid-related complaints.

PMID:41730220 | DOI:10.2196/82865

J Med Internet Res. 2026 Feb 23;28:e86262. doi: 10.2196/86262.

ABSTRACT

BACKGROUND: Traditional cognitive screening relies on episodic clinical assessments and may miss early changes preceding cognitive impairment and dementia. Wearable and mobile health technologies enable continuous monitoring of sleep, physical activity, and circadian rhythms, generating digital biomarkers that may support scalable early detection and prevention. However, current evidence remains fragmented across devices, analytic approaches, and cognitive outcomes.

OBJECTIVE: This study synthesizes and critically evaluates recent evidence on wearable devices for early detection and prevention of cognitive impairment and dementia, focusing on device categories, cognitive outcomes, analytic approaches, and prevention relevance.

METHODS: We searched PubMed, Scopus, ACM Digital Library, and SpringerLink for peer-reviewed studies published between January 2020 and December 1, 2025. Eligible studies included human participants with a mean age ≥50 years, continuous wearable-derived data collected for ≥24 hours, and validated cognitive outcomes; reviews, protocols, smartphone-only studies, and pharmacological interventions were excluded. Two reviewers independently screened studies, extracted data, and assessed risk of bias using the Appraisal Tool for Cross-Sectional Studies, Newcastle-Ottawa Scale, Cochrane Risk of Bias tool, and Quality Assessment of Diagnostic Accuracy Studies-2. Owing to substantial heterogeneity in devices, outcomes, and analytic methods, quantitative meta-analysis was not feasible; a structured narrative synthesis was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidance. This study was not prospectively registered.

RESULTS: We included 49 studies, with sample sizes ranging from 14 to 91,948 participants (>200,000 total) and a median sample size of 145. Most used research-grade actigraphy (43/49, 87.8%), while fewer used commercial wearables (7/49, 14.3%). Cognitive outcomes most frequently relied on global screening instruments, including the Mini-Mental State Examination (18/49, 36.7%), followed by ICD-10 (International Statistical Classification of Diseases, Tenth Revision)-based clinical diagnoses (7/49, 14.3%) and the Montreal Cognitive Assessment (7/49, 14.3%). Analytic approaches were predominantly statistical (36/49, 73.5%), with fewer studies applying machine learning (7/49, 14.3%) or deep learning methods (6/49, 12.2%). Statistical analyses linked disrupted sleep, circadian rhythm fragmentation, and irregular activity patterns to worse cognitive outcomes, with modest-to-moderate effect sizes. Machine learning and deep learning approaches reported classification performance with area under the curve values between approximately 0.70 and 0.95. Approximately one-quarter of the studies (13/49, 26.5%) addressed early detection or prevention through longitudinal risk estimation or predictive modeling. Key limitations included small sample sizes, short monitoring durations, and limited external validation.

CONCLUSIONS: Wearable-derived behavioral markers show promise for early risk stratification. This review advances the field by shifting from descriptive associations toward a digital phenotyping framework evaluating artificial intelligence-driven prediction in the preclinical window. Unlike prior reviews focused on established dementia, it differentiates direct predictive evidence from indirect correlational findings and critically assesses methodological maturity. Continuous, passive monitoring may enable scalable detection of subtle behavioral changes, supporting earlier and more personalized risk reduction strategies.

PMID:41730193 | DOI:10.2196/86262

J Neurosurg Case Lessons. 2026 Feb 23;11(8):CASE25725. doi: 10.3171/CASE25725. Print 2026 Feb 23.

ABSTRACT

BACKGROUND: While deep brain stimulation (DBS) is an effective therapy for essential tremor (ET), Gamma Knife radiosurgery (GKRS) offers a noninvasive alternative for patients who are poor surgical candidates or who experience DBS-related complications. Although GKRS ventral intermediate nucleus (VIM) thalamotomy is generally safe, very delayed adverse effects are uncommon and not well characterized.

OBSERVATIONS: A 69-year-old woman with medically refractory ET underwent right VIM DBS, but the device was later explanted due to infection. Because she was high-risk for reimplantation, she proceeded with GKRS VIM thalamotomy. Eight years later, she developed progressive left-sided weakness and gait deviation. MRI revealed a new right thalamic cystic lesion precisely colocalized with the prior GKRS target. Stereotactic aspiration demonstrated acellular, proteinaceous fluid without evidence of malignancy or infection, consistent with a delayed postradiosurgical cyst. Neurological function improved following drainage.

LESSONS: Delayed cyst formation may occur many years after GKRS VIM thalamotomy and should be recognized as a rare but clinically significant late complication. Given the typical 7- to 10-year latency observed across radiosurgical cystogenesis, long-term but low-frequency MRI surveillance, such as a 1-year posttreatment baseline followed by imaging every 2-3 years or sooner with new neurological symptoms, may facilitate earlier detection and intervention. https://thejns.org/doi/10.3171/CASE25725.

PMID:41730189 | DOI:10.3171/CASE25725

J Neurosurg Case Lessons. 2026 Feb 23;11(8):CASE25667. doi: 10.3171/CASE25667. Print 2026 Feb 23.

ABSTRACT

BACKGROUND: For small- to medium-sized vestibular schwannomas, especially in patients with preserved hearing and no mass-effect symptoms, Gamma Knife radiosurgery (GKRS) is a preferred initial treatment. It provides effective tumor control and long-term hearing preservation. In the event of a tumor progression, reirradiation remains an option. A rare occurrence is the development of a second schwannoma along the same nerve. In such cases, repeat GKRS can be challenging, as it requires balancing local control with minimizing integral radiation dose and potential toxicity from reirradiation. The authors highlight the feasibility of repeat GKRS and the dosimetric considerations involved in radiating a second schwannoma along the same nerve.

OBSERVATIONS: A 35-year-old woman with a history of headaches and a right-sided vestibular schwannoma underwent GKRS as treatment for the tumor. After being under surveillance from 2013 to 2025, the patient’s vestibular schwannoma remained stable. After experiencing a worsening right-sided tinnitus, an updated MRI study revealed a new intracanalicular nodular formation along the nerve, which was treated with GKRS.

LESSONS: This case demonstrates the safety and efficacy of GKRS as a retreatment option in the rare occurrence of a second vestibular schwannoma developing along the same cranial nerve. https://thejns.org/doi/10.3171/CASE25667.

PMID:41730187 | DOI:10.3171/CASE25667