Browsing by Author "Williams, Taylor"

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    Decreased SIRT1 Activity Is Involved in the Acute Injury Response of Chondrocytes to Ex Vivo Injurious Mechanical Overload
    (MDPI, 2023-03-30) Karnik, Sonali; Noori-Dokht, Hessam; Williams, Taylor; Joukar, Amin; Trippel, Stephen B.; Sankar, Uma; Wagner, Diane R; Mechanical and Energy Engineering, School of Engineering and Technology
    A better understanding of molecular events following cartilage injury is required to develop treatments that prevent or delay the onset of trauma-induced osteoarthritis. In this study, alterations to SIRT1 activity in bovine articular cartilage explants were evaluated in the 24 h following a mechanical overload, and the effect of pharmacological SIRT1 activator SRT1720 on acute chondrocyte injury was assessed. SIRT1 enzymatic activity decreased as early as 5 min following the mechanical overload, and remained suppressed for at least 24 h. The chondrocyte injury response, including apoptosis, oxidative stress, secretion of inflammatory mediators, and alterations in cartilage matrix expression, was prevented with pharmacological activation of SIRT1 in a dose-dependent manner. Overall, the results implicate SIRT1 deactivation as a key molecular event in chondrocyte injury following a mechanical impact overload. As decreased SIRT1 signaling is associated with advanced age, these findings suggest that downregulated SIRT1 activity may be common to both age-related and injury-induced osteoarthritis.
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    A Photochemical Crosslinking Approach to Enhance Resistance to Mechanical Wear and Biochemical Degradation of Articular Cartilage
    (Sage, 2022) Noori-Dokht, Hessam; Joukar, Amin; Karnik, Sonali; Williams, Taylor; Trippel, Stephen B.; Wagner, Diane R.; Mechanical and Energy Engineering, School of Engineering and Technology
    Objective: The objective of this study was to evaluate photochemical crosslinking using Al(III) phthalocyanine chloride tetrasulfonic acid (CASPc) and light with a wavelength of 670 nm as a potential therapy to strengthen articular cartilage and prevent tissue degradation. Design: Changes in viscoelastic properties with indentation were used to identify 2 crosslinking protocols for further testing. Crosslinked cartilage was subjected to an in vitro, accelerated wear test. The ability of the crosslinked tissue to resist biochemical degradation via collagenase was also measured. To better understand how photochemical crosslinking with CASPc varies through the depth of the tissue, the distribution of photo-initiator and penetration of light through the tissue depth was characterized. Finally, the effect of CASPc on chondrocyte viability and of co-treatment with an antioxidant was evaluated. Results: The equilibrium modulus was the most sensitive viscoelastic measure of crosslinking. Crosslinking decreased both mechanical wear and collagenase digestion compared with control cartilage. These beneficial effects were realized despite the fact that crosslinking appeared to be localized to a region near the articular surface. In addition, chondrocyte viability was maintained in crosslinked tissue treated with antioxidants. Conclusion: These results suggest that photochemical crosslinking with CASPc and 670 nm light holds promise as a potential therapy to prevent cartilage degeneration by protecting cartilage from mechanical wear and biochemical degradation. Limitations were also evident, however, as an antioxidant treatment was necessary to maintain chondrocyte viability in crosslinked tissue.
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    The impact of clinical genome sequencing in a global population with suspected rare genetic disease
    (Elsevier, 2024) Thorpe, Erin; Williams, Taylor; Shaw, Chad; Chekalin, Evgenii; Ortega, Julia; Robinson, Keisha; Button, Jason; Jones, Marilyn C.; Del Campo, Miguel; Basel, Donald; McCarrier, Julie; Davis Keppen, Laura; Royer, Erin; Foster-Bonds, Romina; Duenas-Roque, Milagros M.; Urraca, Nora; Bosfield, Kerri; Brown, Chester W.; Lydigsen, Holly; Mroczkowski, Henry J.; Ward, Jewell; Sirchia, Fabio; Giorgio, Elisa; Vaux, Keith; Peña Salguero, Hildegard; Lumaka, Aimé; Mubungu, Gerrye; Makay, Prince; Ngole, Mamy; Tshilobo Lukusa, Prosper; Vanderver, Adeline; Muirhead, Kayla; Sherbini, Omar; Lah, Melissa D.; Anderson, Katelynn; Bazalar-Montoya, Jeny; Rodriguez, Richard S.; Cornejo-Olivas, Mario; Milla-Neyra, Karina; Shinaw, Marwan; Magoulas, Pilar; Henry, Duncan; Gibson, Kate; Wiaf, Samuel; Jayakar, Parul; Salyakina, Daria; Masser-Frye, Diane; Serize, Arturo; Perez, Jorge E.; Taylor, Alan; Shenbagam, Shruti; Tayoun, Ahmad Abou; Malhotra, Alka; Bennett, Maren; Rajan, Vani; Avecilla, James; Warren, Andrew; Arseneault, Max; Kalista, Tasha; Crawford, Ali; Ajay, Subramanian S.; Perry, Denise L.; Belmont, John; Taft, Ryan J.; Medicine, School of Medicine
    There is mounting evidence of the value of clinical genome sequencing (cGS) in individuals with suspected rare genetic disease (RGD), but cGS performance and impact on clinical care in a diverse population drawn from both high-income countries (HICs) and low- and middle-income countries (LMICs) has not been investigated. The iHope program, a philanthropic cGS initiative, established a network of 24 clinical sites in eight countries through which it provided cGS to individuals with signs or symptoms of an RGD and constrained access to molecular testing. A total of 1,004 individuals (median age, 6.5 years; 53.5% male) with diverse ancestral backgrounds (51.8% non-majority European) were assessed from June 2016 to September 2021. The diagnostic yield of cGS was 41.4% (416/1,004), with individuals from LMIC sites 1.7 times more likely to receive a positive test result compared to HIC sites (LMIC 56.5% [195/345] vs. HIC 33.5% [221/659], OR 2.6, 95% CI 1.9-3.4, p < 0.0001). A change in diagnostic evaluation occurred in 76.9% (514/668) of individuals. Change of management, inclusive of specialty referrals, imaging and testing, therapeutic interventions, and palliative care, was reported in 41.4% (285/694) of individuals, which increased to 69.2% (480/694) when genetic counseling and avoidance of additional testing were also included. Individuals from LMIC sites were as likely as their HIC counterparts to experience a change in diagnostic evaluation (OR 6.1, 95% CI 1.1-∞, p = 0.05) and change of management (OR 0.9, 95% CI 0.5-1.3, p = 0.49). Increased access to genomic testing may support diagnostic equity and the reduction of global health care disparities.