Citations

Abstract Foxp3⁺ regulatory T cells (Tregs) maintain immune homeostasis, yet the process that preserves their stability during aging remain unclear. Mechanistic progress has been hindered by models that ablate Tregs or delete Foxp3 , which induce acute autoimmunity and prevent longitudinal study of physiological regulatory drift. Here, we establish a dose-dependent mitochondrial framework that preserves Treg lineage survival while permitting gradual metabolic attenuation. Using Treg-restricted TFAM modulation, a complementary haploinsufficient model, and whole-spleen single-cell profiling. We identify lineage-selective immune remodeling characterized by contraction of naïve CD8⁺ and follicular B-cell pools, alteration of CD4⁺ states, expansion of activated Tregs, and emergence of neuroimmune stress linked transcriptional modules that parallel physiological aging. Mechanistically, mitochondrial insufficiency is associated with functional loss of FOXP3- centered chromatin coordination and enrichment of NF-κB/NFAT/AP-1 inflammatory and senescence programs while lineage identity remains detectable. Partial mitochondrial attenuation within Tregs alone is sufficient to drive chronic low-grade systemic inflammation, neuromuscular decline, gut microbial restructuring, and elevated microglial responsiveness without Treg depletion. Pharmacologic and microbiota-directed interventions partially reduce inflammatory tone and improve functional metrics. Together, our findings identify TFAM as a key regulator of immune aging and reveal that healthy mitochondrial function in Tregs is essential for protecting against inflammaging and age-associated functional decline.

Abstract The methodological procedure for generating three-dimensional (3-D) finite element analysis (FEA) geometry models from CT or MRI medical imaging scan data was developed in this study. Medical images of a human scapula and a fifth proximal phalangeal bone were used to demonstrate the techniques of image processing and generation of 3-D FEA models. The biomedical imaging quality and its effects on the outcome of the FEA geometry model was also studied.

OBJECTIVE Combinations of certain social risk factors of race, sex, education, socioeconomic status (SES), insurance, education, employment, and one’s housing situation have been associated with poorer pain and disability outcomes after lumbar spine surgery. To date, an exploration of such factors in patients with cervical spine surgery has not been conducted. The objective of the current work was to 1) define the social risk phenotypes of individuals who have undergone cervical spine surgery for myelopathy and 2) analyze their predictive capacity toward disability, pain, quality of life, and patient satisfaction–based outcomes. METHODS The Cervical Myelopathy Quality Outcomes Database was queried for the period from January 2016 to December 2018. Race/ethnicity, educational attainment, SES, insurance payer, and employment status were modeled into unique social phenotypes using latent class analyses. Proportions of social groups were analyzed for demonstrating a minimal clinically important difference (MCID) of 30% from baseline for disability, neck and arm pain, quality of life, and patient satisfaction at the 3-month and 1-year follow-ups. RESULTS A total of 730 individuals who had undergone cervical myelopathy surgery were included in the final cohort. Latent class analysis identified 2 subgroups: 1) high risk (non-White race and ethnicity, lower educational attainment, not working, poor insurance, and predominantly lower SES), n = 268, 36.7% (class 1); and 2) low risk (White, employed with good insurance, and higher education and SES), n = 462, 63.3% (class 2). For both 3-month and 1-year outcomes, the high-risk group (class 1) had decreased odds (all p < 0.05) of attaining an MCID score in disability, neck/arm pain, and health-related quality of life. Being in the low-risk group (class 2) resulted in an increased odds of attaining an MCID score in disability, neck/arm pain, and health-related quality of life. Neither group had increased or decreased odds of being satisfied with surgery. CONCLUSIONS Although 2 groups underwent similar surgical approaches, the social phenotype involving non-White race/ethnicity, poor insurance, lower SES, and poor employment did not meet MCIDs for a variety of outcome measures. This finding should prompt surgeons to proactively incorporate socially conscience care pathways within healthcare systems, as well as to optimize community-based resources to improve outcomes and personalize care for populations at social risk.

Abstract Only recently has the rodent hippocampus been implicated in orexigenic appetitive processing1,2. This function has been found to be mediated at least in part by lateral hypothalamic inputs involving an orexigenic neuropeptide, melanin-concentrating hormone3. This circuit remains elusive in humans. Here, we combine tractography, intracranial electrophysiology, cortico-subcortical evoked potentials, and brain-clearing 3D histology to identify an orexigenic circuit involving the lateral hypothalamus converging in a hippocampal subregion. We found that low-frequency power is modulated by sweet-fat food cues and this modulation was specific to the dorsolateral hippocampus. Lastly, structural and functional analyses of this circuit in a human cohort exhibiting dysregulated eating behavior revealed connectivity that was inversely related to body mass index. Collectively, this multimodal approach describes an orexigenic subnetwork within the human hippocampus implicated in obesity and related eating disorders.

Abstract Background Brainstem toxicity after radiation therapy (RT) is a devastating complication and a particular concern with proton radiation (PBT). We investigated the incidence and clinical correlates of brainstem injury in pediatric brain tumors treated with PBT. Methods All patients &lt;21 years with brain tumors treated with PBT at our institution from 2007–2019, with a brainstem Dmean &gt;30 Gy and/or Dmax &gt;50.4 Gy were included. Symptomatic brainstem injury (SBI) was defined as any new or progressive cranial neuropathy, ataxia, and/or motor weakness with corresponding radiographic abnormality within brainstem. Results A total of 595 patients were reviewed and 468 (medulloblastoma = 200, gliomas = 114, ependymoma = 87, ATRT = 43) met our inclusion criteria. Median age at RT was 6.3 years and median prescribed RT dose was 54Gy [RBE]. Fifteen patients (3.2%) developed SBI, at a median of 4 months after RT. Grades 2, 3, 4, and 5 brainstem injuries were seen in 7, 5, 1, and 2 patients respectively. Asymptomatic radiographic changes were seen in 51 patients (10.9%). SBI was significantly higher in patients with age ≤3 years, female gender, ATRT histology, patients receiving high-dose chemotherapy with stem cell rescue, and those not receiving craniospinal irradiation. Patients with SBI had a significantly higher V50–52. In 2014, our institution started using strict brainstem dose constraints (Dmax ≤57 Gy, Dmean ≤52.4 Gy, and V54≤10%). There was a trend towards decrease in SBI from 4.4% (2007-2013) to 1.5% (2014–2019) (P = .089) without affecting survival. Conclusion Our results suggest a low risk of SBI after PBT for pediatric brain tumors, comparable to photon therapy. A lower risk was seen after adopting strict brainstem dose constraints.

Abstract A theoretical model has been developed based on fuzzy logic control to predict bony response to mechanical load and estrogen. The results show good agreement with the experimental findings, which suggests that bone may be regulated by simple remodeling rules, similar to those used in the fuzzy logic control.

Abstract An optical tweezers system has been adopted for molecular biomechanical testing. To achieve nanometer manipulation and measurement, the system was modified with a piezo-stage and an interferometer. A systematic calibration was then performed on the displacement resolution. The results revealed that the system has a nanometer resolution which is sufficient for the measurement of deformation and stiffness of single macro-molecules.

Abstract Electromyography (EMG) measurement has been the one of the major sources of information to understand the neuromuscular control of human locomotion, while a limited amount of knowledge is available due to its complicate signal structure. Other measurable parameters may be of little value in extracting the neuromuscular information without having a precise mechanical relationship.

Abstract The prevalence of rotator cuff disease among the elderly population and the greatest incidence of acute dislocations will continue to provide challenging patient management decisions. Stability of the shoulder is critical to successful upper extremity function. The GH joint is stabilized by passive capsuloligamentous restraints as well as by active dynamic stabilizers through concavity compression. The compression of the convex humeral head (HH) into the concave glenoid fossa (GF) counteracts against translational shear forces (Matsen et. al 1994). The major compressive load across the joint is provided by the action of the surrounding musculature, especially the rotator cuff. The muscles may generate both compressive and shear force components as well as moments. The purpose of this study is to describe a new testing methodology of how to estimate the contribution of individual rotator cuff muscles to the dynamic stability of the GH joint at a given joint position.