@article{ludwig_abraham_mckinney_freund_stewart_garman_barbas_sudan_gonzalez_2023, title={45: Comparison of the Effects of Normothermic Machine Perfusion and Cold Storage Preservation on Porcine Intestinal Allograft Regenerative Potential and Viability}, volume={107}, ISSN={0041-1337}, url={http://dx.doi.org/10.1097/01.tp.0000945636.34372.db}, DOI={10.1097/01.tp.0000945636.34372.db}, abstractNote={Historically, intestinal transplantation (IT) has been reserved as the last treatment option for patients with irreversible intestinal failure who are unable to tolerate total parenteral nutrition. Successful IT is reliant upon graft health at the time of donation, minimizing graft injury that may occur during procurement, storage, and IT, and the ability of the graft to heal following insult. Unfortunately, the intestine is easily damaged by ischemia-reperfusion injury (IRI). IRI induces intestinal epithelial cell apoptosis and damages the mucosal barrier, which can result in bacterial translocation and activation of the local and systemic immune and inflammatory response, ultimately contributing to graft failure, rejection, and decreased recipient survival. The current, preferred method of intestinal preservation prior to IT is static cold storage (CS), however the prolonged hypothermic ischemia of CS causes cell injury and intensifies the IRI that occurs during transplantation. Furthermore, IRI to the epithelial crypt region diminishes the intestine’s ability to heal by inducing loss of the highly proliferative intestinal stem cells (ISCs) that are responsible for maintenance, regeneration, and repair of the epithelium, critical to graft health. Thus, the investigation of alternative organ preservation techniques that reduce IRI, cellular damage, and graft injury are warranted to overall improve IT success. Normothermic machine perfusion (NMP) is a preservation method that reduces inflammation and promotes graft regeneration in other organs by preventing CS-associated IRI. However, NMP has not been described for intestine. We hypothesized that, compared to CS, intestinal NMP will induce less epithelial injury and better protect ISC regenerative potential and viability. 15 porcine intestines were flushed with UW solution, stored at 4°C (CS), or perfused with 34°C perfusate (NMP) for 6hr, and transplanted (n=9). Recipient pigs were recovered from anesthesia. Jejunal and ileal segments were collected immediately after flushing, serving as control tissue (CO), after 6hr of CS or NMP, and after 1hr of reperfusion post-IT. Histologic injury was assessed. Crypts isolated after flushing (CO), 6hr CS or NMP, and 1hr of reperfusion post-IT were cultured. Spheroid number, size, and EdU staining quantified ISC viability and proliferation. Expression of ISC and cellular proliferation genes and proteins were measured. Histologically, NMP tissue had mild epithelial erosion and increased columnar cell attenuation and expression of ISC and proliferation genes/proteins was observed. NMP spheroid areas and proliferating cell numbers were significantly larger than control and CS. Apoptotic cells were increased following CS. Post-graft reperfusion, CS had increased injury compared to uninjured control and NMP tissue. Compared to CS, NMP may improve graft regenerative potential, resulting in transplantation of healthier bowel and superior recipient survival.}, number={7S}, journal={Transplantation}, publisher={Ovid Technologies (Wolters Kluwer Health)}, author={Ludwig, Elsa and Abraham, Nader and McKinney, Caroline and Freund, John and Stewart, Amy and Garman, Katherine and Barbas, Andrew and Sudan, Debra and Gonzalez, Liara}, year={2023}, month={Jun}, pages={25–25} }
 @article{ludwig_hallowell_womble_o'neil_2023, title={Bilateral patellar aplasia in a foal}, ISSN={["2053-1095"]}, DOI={10.1002/vms3.1083}, abstractNote={Abstract}, journal={VETERINARY MEDICINE AND SCIENCE}, author={Ludwig, Elsa K. and Hallowell, Kim and Womble, Mandy and O'Neil, Erin}, year={2023}, month={Feb} }
 @article{ludwig_hobbs_mckinney-aguirre_gonzalez_2023, title={Biomarkers of Intestinal Injury in Colic}, volume={13}, ISSN={2076-2615}, url={http://dx.doi.org/10.3390/ani13020227}, DOI={10.3390/ani13020227}, abstractNote={Biomarkers are typically proteins, enzymes, or other molecular changes that are elevated or decreased in body fluids during the course of inflammation or disease. Biomarkers pose an extremely attractive tool for establishing diagnoses and prognoses of equine gastrointestinal colic, one of the most prevalent causes of morbidity and mortality in horses. This topic has received increasing attention because early diagnosis of some forms of severe colic, such as intestinal ischemia, would create opportunities for rapid interventions that would likely improve case outcomes. This review explores biomarkers currently used in equine medicine for colic, including acute phase proteins, proinflammatory cytokines, markers of endotoxemia, and tissue injury metabolites. To date, no single biomarker has been identified that is perfectly sensitive and specific for intestinal ischemia; however, L-lactate has been proven to be a very functional and highly utilized diagnostic tool. However, further exploration of other biomarkers discussed in this review may provide the key to accelerated identification, intervention, and better outcomes for horses suffering from severe colic.}, number={2}, journal={Animals}, publisher={MDPI AG}, author={Ludwig, Elsa K. and Hobbs, Kallie J. and McKinney-Aguirre, Caroline A. and Gonzalez, Liara M.}, year={2023}, month={Jan}, pages={227} }
 @article{veerasammy_gonzalez_báez‐ramos_schaaf_stewart_ludwig_mckinney‐aguirre_freund_robertson_gonzalez_2023, title={Changes in equine intestinal stem/progenitor cell number at resection margins in cases of small intestinal strangulation}, volume={55}, ISSN={0425-1644 2042-3306}, url={http://dx.doi.org/10.1111/evj.13927}, DOI={10.1111/evj.13927}, abstractNote={Abstract}, number={6}, journal={Equine Veterinary Journal}, publisher={Wiley}, author={Veerasammy, Brittany and Gonzalez, Gabriel and Báez‐Ramos, Patricia and Schaaf, Cecilia R. and Stewart, Amy Stieler and Ludwig, Elsa K. and McKinney‐Aguirre, Caroline and Freund, John and Robertson, James and Gonzalez, Liara M.}, year={2023}, month={Feb}, pages={995–1002} }
 @article{ludwig_abraham_schaaf_mckinney_freund_stewart_veerasammy_thomas_cardona_garman_et al._2023, title={Comparison of the effects of normothermic machine perfusion and cold storage preservation on porcine intestinal allograft regenerative potential and viability}, volume={24}, ISSN={1600-6135}, url={http://dx.doi.org/10.1016/j.ajt.2023.10.026}, DOI={10.1016/j.ajt.2023.10.026}, abstractNote={<h2>Abstract</h2> Intestinal transplantation (IT) is the final treatment option for intestinal failure. Static cold storage (CS) is the standard preservation method used for intestinal allografts. However, CS and subsequent transplantation induce ischemia-reperfusion injury (IRI). Severe IRI impairs epithelial barrier function, including loss of intestinal stem cells (ISC), critical to epithelial regeneration. Normothermic machine perfusion (NMP) preservation of kidney and liver allografts minimizes CS-associated IRI; however, it has not been used clinically for IT. We hypothesized that intestine NMP would induce less epithelial injury and better protect the intestine's regenerative ability when compared with CS. Full-length porcine jejunum and ileum were procured, stored at 4 °C, or perfused at 34 °C for 6 hours (T6), and transplanted. Histology was assessed following procurement (T0), T6, and 1 hour after reperfusion. Real-time quantitative reverse transcription polymerase chain reaction, immunofluorescence, and crypt culture measured ISC viability and proliferative potential. A greater number of NMP-preserved intestine recipients survived posttransplant, which correlated with significantly decreased tissue injury following 1-hour reperfusion in NMP compared with CS samples. Additionally, ISC gene expression, spheroid area, and cellular proliferation were significantly increased in NMP-T6 compared with CS-T6 intestine. NMP appears to reduce IRI and improve graft regeneration with improved ISC viability and proliferation.}, number={4}, journal={American Journal of Transplantation}, publisher={Elsevier BV}, author={Ludwig, Elsa K. and Abraham, Nader and Schaaf, Cecilia R. and McKinney, Caroline A. and Freund, John and Stewart, Amy S. and Veerasammy, Brittany A. and Thomas, Mallory and Cardona, Diana M. and Garman, Katherine and et al.}, year={2023}, month={Oct}, pages={564–576} }
 @article{hobbs_young_nannarone_luethy_hopster-iversen_mckenzie_ludwig_2023, title={Intravenous loss of over-the-wire catheter guidewires in 13 horses}, volume={12}, ISSN={["1939-1676"]}, url={https://doi.org/10.1111/jvim.16960}, DOI={10.1111/jvim.16960}, abstractNote={Abstract}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Hobbs, Kallie J. and Young, Kimberly A. S. and Nannarone, Sara and Luethy, Daniela and Hopster-Iversen, Charlotte and Mckenzie, Harold C. and Ludwig, Elsa K.}, year={2023}, month={Dec} }
 @article{abraham_ludwig_schaaf_veerasammy_stewart_mckinney_freund_brassil_samy_gao_et al._2022, title={Orthotopic Transplantation of the Full-length Porcine Intestine After Normothermic Machine Perfusion}, volume={8}, ISSN={2373-8731}, url={http://dx.doi.org/10.1097/TXD.0000000000001390}, DOI={10.1097/TXD.0000000000001390}, abstractNote={
            Background.
            Successful intestinal transplantation is currently hindered by graft injury that occurs during procurement and storage, which contributes to postoperative sepsis and allograft rejection. Improved graft preservation may expand transplantable graft numbers and enhance posttransplant outcomes. Superior transplant outcomes have recently been demonstrated in clinical trials using machine perfusion to preserve the liver. We hypothesized that machine perfusion preservation of intestinal allografts could be achieved and allow for transplantation in a porcine model.
          }, number={11}, journal={Transplantation Direct}, publisher={Ovid Technologies (Wolters Kluwer Health)}, author={Abraham, Nader and Ludwig, Elsa K. and Schaaf, Cecilia R. and Veerasammy, Brittany and Stewart, Amy S. and McKinney, Caroline and Freund, John and Brassil, John and Samy, Kannan P. and Gao, Qimeng and et al.}, year={2022}, month={Oct}, pages={e1390} }