Browsing by Author "Lopez, David"

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    Cx43 Overexpression in Osteocytes Prevents Osteocyte Apoptosis and Preserves Cortical Bone Quality in Aging Mice
    (Wiley, 2018-02-26) Davis, Hannah M.; Aref, Mohammad W.; Aguilar‐Perez, Alexandra; Pacheco‐Costa, Rafael; Allen, Kimberly; Valdez, Sinai; Herrera, Carmen; Atkinson, Emily G.; Mohammad, Arwa; Lopez, David; Harris, Marie A.; Harris, Stephen E.; Allen, Matthew; Bellido, Teresita; Plotkin, Lilian I.; Anatomy and Cell Biology, School of Medicine
    Young, skeletally mature mice lacking Cx43 in osteocytes exhibit increased osteocyte apoptosis and decreased bone strength, resembling the phenotype of old mice. Further, the expression of Cx43 in bone decreases with age, suggesting a contribution of reduced Cx43 levels to the age-related changes in the skeleton. We report herein that Cx43 overexpression in osteocytes achieved by using the DMP1-8kb promoter (Cx43OT mice) attenuates the skeletal cortical but not trabecular bone phenotype of aged, 14-month-old mice. The percentage of Cx43-expressing osteocytes was higher in Cx43OT mice, whereas the percentage of Cx43-positive osteoblasts remained similar to wild-type (WT) littermate control mice. The percentage of apoptotic osteocytes and osteoblasts was increased in aged WT mice compared with skeletally mature, 6-month-old WT mice, and the percentage of apoptotic osteocytes, but not osteoblasts, was decreased in age-matched Cx43OT mice. Aged WT mice exhibited decreased bone formation and increased bone resorption as quantified by histomorphometric analysis and circulating markers compared with skeletally mature mice. Further, aged WT mice exhibited the expected decrease in bone biomechanical structural and material properties compared with young mice. Cx43 overexpression prevented the increase in osteoclasts and decrease in bone formation on the endocortical surfaces and the changes in circulating markers in the aged mice. Moreover, the ability of bone to resist damage was preserved in aged Cx43OT mice both at the structural and material level. All together, these findings suggest that increased Cx43 expression in osteocytes ameliorates age-induced cortical bone changes by preserving osteocyte viability and maintaining bone formation, leading to improved bone strength. © 2018 American Society for Bone and Mineral Research.
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    Feasibility of a virtual reality intervention in the intensive care unit
    (Elsevier, 2021) Jawed, Yameena T.; Golovyan, Dmitriy; Lopez, David; Khan, Sikandar H.; Wang, Sophia; Freund, Chauncey; Imran, Sundus; Bin Hameed, Usman; Smith, Joseph P.; Kok, Lotte; Khan, Babar A.; Medicine, School of Medicine
    Background: Delirium prevention requires optimal management of pain and anxiety. Given the limitations of current pharmacologic interventions, evaluation of novel non-pharmacological interventions is required. Virtual reality (VR) stimulation may be a promising intervention because of its capability to reduce psychophysiological stress, pain, and anxiety and to restore cognitive and attentional capacities. Objective: To ascertain patients' and providers' perceptions of acceptability and safety of VR intervention in the intensive care unit (ICU). Methods: We enrolled a cohort of 15 ICU patients and 21 health care providers to administer a 15-minute session showing a relaxing beach scene with VR headsets and nature sound effects. Participants were then asked to rate their experiences on a Likert scale survey. Results: The majority of patients (86%, 12 of 14) rated the headsets as moderately to very comfortable. All had moderate or greater sense of presence in the virtual environment, and 79% (11 of 14) rated their overall experience at 3 or greater (5 indicating that they enjoyed it very much). Seventy-one percent (10 of 14) of the patients felt that their anxiety was better with VR, and 57% (8 of 14) did not notice a change in their pain or discomfort. All health care providers found the headset to be at least moderately comfortable and felt a moderate or greater sense of presence. All providers concluded that VR therapy should be available for their patients. Both groups experienced minimal side effects. Conclusion: In this prospective study of perceptions of VR therapy for ICU patients and health care providers, there was a high level of acceptance, with minimal side effects, for both groups despite their low levels of prior experience with virtual reality and video gaming.
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    Releasing the brakes: a case report of pulmonary arterial hypertension induced by immune checkpoint inhibitor therapy
    (Wiley, 2020-10) Glick, Matthew; Baxter, Chase; Lopez, David; Mufti, Kashif; Sawada, Stephen; Lahm, Tim; Medicine, School of Medicine
    Immune checkpoint inhibitors successfully treat various malignancies by inducing an immune response to tumor cells. However, their use has been associated with a variety of autoimmune disorders, such as diabetes, hepatitis, and pneumonitis. Pulmonary arterial hypertension due to checkpoint inhibitor use has not yet been described. We present a novel case of pulmonary arterial hypertension associated with systemic lupus erythematosus and Sjogren’s syndrome overlap that was induced by therapy with the checkpoint inhibitor durvalumab.