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The global loss of heterochromatin during ageing has been observed in eukaryotes from yeast to humans, and this has been proposed as one of the causes of ageing. However, the cause of this age-associated loss of heterochromatin has remained enigmatic. Here we show that heterochromatin markers, including histone H3K9 di/tri-methylation and HP1, decrease with age in muscle stem cells (MuSCs) as a consequence of the depletion of the methyl donor S-adenosylmethionine (SAM). We find that restoration of intracellular SAM in aged MuSCs restores heterochromatin content to youthful levels and rejuvenates age-associated features, including DNA damage accumulation, increased cell death, and defective muscle regeneration. SAM is not only a methyl group donor for transmethylation, but it is also an aminopropyl donor for polyamine synthesis. Excessive consumption of SAM in polyamine synthesis may reduce its availability for transmethylation. Consistent with this premise, we observe that perturbation of increased polyamine synthesis by inhibiting spermidine synthase restores intracellular SAM content and heterochromatin formation, leading to improvements in aged MuSC function and regenerative capacity in male and female mice. Together, our studies demonstrate a direct causal link between polyamine metabolism and epigenetic dysregulation during murine MuSC ageing.

ObjectivesTherapeutic virtual reality (VR) has emerged as an effective, drug-free tool for pain management, but there is a lack of randomized, controlled data evaluating its effectiveness in hospitalized patients. We sought to measure the impact of on-demand VR versus "health and wellness" television programming for pain in hospitalized patients.MethodsWe performed a prospective, randomized, comparative effectiveness trial in hospitalized patients with an average pain score of ≥3 out of 10 points. Patients in the experimental group received a library of 21 VR experiences administered using the Samsung Gear Oculus headset; control patients viewed specialized television programming to promote health and wellness. Clinical staff followed usual care; study interventions were not protocolized. The primary outcome was patient-reported pain using a numeric rating scale, as recorded by nursing staff during usual care. Pre- and post-intervention pain scores were compared immediately after initial treatment and after 48- and 72-hours.ResultsThere were 120 subjects (61 VR; 59 control). The mean within-subject difference in immediate pre- and post-intervention pain scores was larger in the VR group (-1.72 points; SD 3.56) than in the control group (-0.46 points; SD 3.01); this difference was significant in favor of VR (P < .04). When limited to the subgroup of patients with severe baseline pain (≥7 points), the effect of VR was more pronounced vs. control (-3.04, SD 3.75 vs. -0.93, SD 2.16 points; P = .02). In regression analyses adjusting for pre-intervention pain, time, age, gender, and type of pain, VR yielded a .59 (P = .03) and .56 (P = .04) point incremental reduction in pain versus control during the 48- and 72-hour post-intervention periods, respectively.ConclusionsVR significantly reduces pain versus an active control condition in hospitalized patients. VR is most effective for severe pain. Future trials should evaluate standardized order sets that interpose VR as an early non-drug option for analgesia.

ObjectiveTo evaluate and compare the attitudes and preferences of younger and older adults regarding health information exchange with providers, and identify barriers and limitations to meaningful use.Study designCross-sectional study.MethodsQualitative and quantitative data gathered from online surveys of younger and older adult patients enrolled in a freestanding, Internetbased patient-physician messaging system that requires an individual account. This messaging system is only a secure messaging center, and does not allow for direct access to personal medical records.ResultsData were collected from 324 patients (or proxy users) who reported their age, with 55.2% of respondents under the age of 65 years (mean age 48.2 years) and 44.8% of respondents 65 years or older (mean age 74.9 years). Family and non-family caregivers (proxy users) (mean age 59.2 years) comprised 21.0% of respondents. Overall, 83.9% of all respondents preferred to communicate with the provider via e-mail, and 84.5% of users found the messaging system easy to use, with a majority utilizing the messaging system to communicate about health questions and/or medication requests. Finally, 83% of user respondents were satisfied with the messaging system. Results highlight several areas where improvement is needed to increase patient use and satisfaction including adequate patient education, user-friendly interface, and provider engagement. No significant differences between the younger and older adult populations were found.ConclusionAlthough a majority of enrolled older adult patients have positive attitudes about health information exchange, electronic communication platforms must address key issues in consumer education, physician commitment, and adoption of an accessible interface to ensure productive older adult consumer participation.

Three-dimensional (3D) information plays an important part in medical and veterinary education. Appreciating complex 3D spatial relationships requires a strong foundational understanding of anatomy and mental 3D visualization skills. Novel learning resources have been introduced to anatomy training to achieve this. Objective evaluation of their comparative efficacies remains scarce in the literature. This study developed and evaluated the use of a physical model in demonstrating the complex spatial relationships of the equine foot. It was hypothesized that the newly developed physical model would be more effective for students to learn magnetic resonance imaging (MRI) anatomy of the foot than textbooks or computer-based 3D models. Third year veterinary medicine students were randomly assigned to one of three teaching aid groups (physical model; textbooks; 3D computer model). The comparative efficacies of the three teaching aids were assessed through students' abilities to identify anatomical structures on MR images. Overall mean MRI assessment scores were significantly higher in students utilizing the physical model (86.39%) compared with students using textbooks (62.61%) and the 3D computer model (63.68%) ("P" less than 0.001), with no significant difference between the textbook and 3D computer model groups ("P" = 0.685). Student feedback was also more positive in the physical model group compared with both the textbook and 3D computer model groups. Our results suggest that physical models may hold a significant advantage over alternative learning resources in enhancing visuospatial and 3D understanding of complex anatomical architecture, and that 3D computer models have significant limitations with regards to 3D learning. (Contains 3 figures.)

Intra‐synovial tendon injuries are a common orthopedic problem with limited treatment options. The synovium is a specialized connective tissue forming the inner encapsulating lining of diarthrodial joints and intra‐synovial tendons. It contains multipotent mesenchymal stromal cells that render it a viable source of progenitors for tendon repair. This study evaluated the effects of autologous implantation of cells derived from normal synovium (synovial membrane cells [SMCs]) in augmenting repair in an ovine model of intra‐synovial tendon injury. For this purpose, synovial biopsies were taken from the right digital flexor tendon sheath following creation of a defect to the lateral deep digital flexor tendon. Mononuclear cells were isolated by partial enzymatic digestion and assessed for MSC characteristics. Cell tracking and tendon repair were assessed by implanting 5 × 106 cells into the digital flexor tendon sheath under ultrasound guidance with the effects evaluated using magnetic resonance imaging and histopathology. Synovial biopsies yielded an average 4.0 × 105 ± 2.7 × 105 SMCs that exhibited a fibroblastic morphology, variable osteogenic, and adipogenic responses but were ubiquitously strongly chondrogenic. SMCs displayed high expression of CD29 with CD271NEGATIVE and MHC‐IILOW cell‐surface marker profiles, and variable expression of CD73, CD90, CD105, CD166, and MHC‐I. Implanted SMCs demonstrated engraftment within the synovium, though a lack of repair of the tendon lesion over 24 weeks was observed. We conclude healthy synovium is a viable source of multipotent cells, but that the heterogeneity of synovium underlies the variability between different SMC populations, which while capable of engraftment and persistence within the synovium exhibit limited capacity of influencing tendon repair. © 2019 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society J Orthop Res 38:128–138, 2020 [ABSTRACT FROM AUTHOR]