alyce jones | Old Dominion University (original) (raw)

Papers by alyce jones

Cryopreserved allograft heart valves represent the best solution for a patient with a failing hea... more Cryopreserved allograft heart valves represent the best solution for a patient with a failing heart valve. However, the constituent cells become apoptotic and within months of transplant the heart valve becomes acellular and the recipient's cells do not repopulate the allograft (3, 51). A strategy to prevent this situation would be to minimize or prevent apoptosis from occurring by strategically altering steps during heart valve processing. Recently it has been demonstrated that: 1) Heat shock protein 70 is a negative modulator of the apoptotic cascade; 2) Cells in culture exposed to hypothermic conditions produce heat shock protein 70 upon rewarming; and 3) Glutamine can induce heat shock protein 70 production. The purpose of the current research is to apply these vii TABLE OF CONTENTS Page LIST OF TABLES ix LIST OF FIGURES x Chapter viii 3.18 STATISTICAL ANALYSIS 4. RESULT 4.1 DONOR VARIABLES 4.2 PROTEIN CONCENTRATION OVER TIME 4.3 GLUTAMINE CONCENTRATION 4.4 HEAT SHOCK PROTEIN 70 QUANTITATION ANTIBIOTIC INCUBATION 4.5 HEAT SHOCK PROTEIN 70 QUANTITATION INCUBATION POST-CRYOPRESERVATION 4.6 CYTOCHROME C QUANTITATION CYTOSOLIC ANALYSIS DURING ANTIBIOTIC INCUBATION 4.7 CYTOCHROME C QUANTITATION CYTOSOLIC ANALYSIS POST-CRYOPRESERVATION 4.8 CYTOCHROME C QUANTITATION MITOCHONDRIAL ANALYSIS DURING ANTIBIOTIC INCUBATION 4.9 CYTOCHROME C QUANTITATION MITOCHONDRIAL ANALYSIS POST-CRYOPRESERVATION 4.10 BCL-2 QUANTITATION-PRECRYOPRESERVATION .. .84 4.11BCL-2 QUANTITATION-POSTCRYOPRESERVATION 4.12CASPASE-3 IMMUNOHISTOCHEMISTRY-PRECRYOPRESERVATION 4.13 CASPASE-3 IMMUNOHISTOCHEMISTRY-POST-CYOPRESERVATION 4.14 VISUALIZATION OF APOPTOTIC CELLS-PRECRYOPRESERVATION 109 4.15 VISUALIZATION OF APOPTOTIC CELLS-POST-CRYOPRESERVATION 113 5. DISCUSSION 123 6. CONCLUSIONS AND FUTURE RESEARCH 135 xi 17. Quantitation of mitochondrial cytochrome c in aortic conduit tissue after Cryopreservation 18. Mitochondrial cytochrome c vs. Hsp70 content over time during post-cryopreservation in the 4°C and 4°C+GLN treatment groups 19. Mitochondrial cytochrome c vs. Hsp70 content in the cells post-cryopreservation in the 37°C and 37°C+GLN treatment groups 20. Cytochrome c content in the mitochondria for each treatment group for the duration of the study-disinfection and post-cryopreservation 21. Quantitation of Bcl-2 in aortic conduit tissue during disinfection under various treatment conditions 22. Bcl-2 vs. Hsp70 content over time during disinfection in the 4°C and 4°C+GLN treatment groups 23. Bcl-2 vs. Hsp70 content over time during disinfection in the 37°C and 37°C+GLN treatment groups 24. Quantitation of Bcl-2 in aortic conduit tissue after cryopreservation 25. Bcl-2 vs. Hsp70 content over time post-cryopreservation in the 4°C and 4°C+GLN treatment groups 26. Bcl-2 vs. Hsp70 content in the cells post-cryopreservation in the 37°C and 37°C+GLN treatment groups 27. Quantitation of caspase-3 in aortic conduit tissue during disinfection under various treatment conditions 28. Caspase-3 vs. Hsp70 content in the cells during.disinfection in the 4°C and 4°C+GLN treatment groups 29. Percentage of Caspase-3 positive cells vs. Hsp70 content over time during disinfection in the 37°C and 37°C+GLN treatment groups 30. Quantitation of caspase-3 in aortic conduit tissue after cryopreservation 98 31. Percentage of Caspase-3 positive cells vs. Hsp70 content in the cells post-cryopreservation in the 4°C and 4°C+GLN treatment groups 99 32. Percentage of caspase-3 positive cells vs. Hsp70 content over time post-cryopreservation in the 37°C and 37°C+GLN treatment groups 100 33. Caspase-3 Positive Control 101 34. Caspase-3 Positive Control 102 xii 35. Caspase-3 Negative Control 36. Baseline caspase-3 staining 104 37. Baseline caspase-3 staining 38. Caspase-3 micrograph, 25% positivity 106 39. Caspase-3 micrograph, 25% positivity 107 40. Caspase-3 micrograph, 45% positivity 108 41. Quantitation of TUNEL positive cells in aortic conduit tissue during disinfection under various treatment conditions 110 42. Percentage of TUNEL positive cells vs. Hsp70 content over time during disinfection in the 4°C and 4°C+GLN treatment groups 43. Percentage of TUNEL positive cells vs. Hsp70 content in the cells during disinfection in the 37°C and 37°C+GLN treatment groups 44. Quantitation of TUNEL positive cells in aortic conduit tissue after Cryopreservation 45. Percentage of TUNEL positive cells vs. Hsp70 content in the cells post-cryopreservation in the 4°C and 4°C+GLN treatment groups 46. Percentage of TUNEL positive cells vs. Hsp70 content in the cells post-cryopreservation in the 37°C and 37°C+GLN treatment groups 47. TUNEL Positive Control 118 48. TUNEL Negative Control 119 49. Baseline TUNEL staining 120 50. TUNEL micrograph, 25% positivity 121 51. TUNEL micrograph, 45% positivity 52. Hsp70 Inductive Signals, Hsp70 Gene Activation and HP70 Synthesis 130 53. Multiple Negative Control Points in the Apoptotic Cascade that Hsp70 Modulates 131

Cell and Tissue Banking, Dec 9, 2022

Given the possibility for disease transmission, this study was performed to determine whether the... more Given the possibility for disease transmission, this study was performed to determine whether there is detectable SARS-CoV-2 viral RNA in the blood of deceased tissue donors. A retrospective analysis of blood samples from eligible deceased tissue donors from Oct 2019 through June 2020 was performed. Plasma aliquots were initially tested with a SARS-CoV-2 NAT Assay; positive samples were further tested using an alternate NAT and an antibody assay. The proportion of donors with confirmed RNAemia and 95% confidence intervals were computed. Of donor samples collected in 2019, 894 yielded valid results, with 6 initially positive, none of which confirmed positive by alternate NAT. Of donor samples collected in 2020, 2562 yielded valid initial NAT results, with 21 (0.8%) initially positive.

Cell and Tissue Banking

Given the possibility for disease transmission, this study was performed to determine whether the... more Given the possibility for disease transmission, this study was performed to determine whether there is detectable SARS-CoV-2 viral RNA in the blood of deceased tissue donors. A retrospective analysis of blood samples from eligible deceased tissue donors from Oct 2019 through June 2020 was performed. Plasma aliquots were initially tested with a SARS-CoV-2 NAT Assay; positive samples were further tested using an alternate NAT and an antibody assay. The proportion of donors with confirmed RNAemia and 95% confidence intervals were computed. Of donor samples collected in 2019, 894 yielded valid results, with 6 initially positive, none of which confirmed positive by alternate NAT. Of donor samples collected in 2020, 2562 yielded valid initial NAT results, with 21 (0.8%) initially positive. Among those, 3 were confirmed by alternate NAT, 17 were not confirmed, and 1 had an invalid alternate NAT result. The rate of SARS-CoV-2 RNAemia in deceased tissue donors is approximately 1 per 1000, an...

LACTATE THRESHOLD: THE COMPARISON OF RUNNING ON A LAND TREADMILL VERSUS HEAD-OUT WATER IMMERSION ... more LACTATE THRESHOLD: THE COMPARISON OF RUNNING ON A LAND TREADMILL VERSUS HEAD-OUT WATER IMMERSION TREADMILL RUNNING. Stephanie Jones Zobell Department of Exercise Sciences Master of Science ABSTRACT Introduction. Exercise and head-out water immersion (HOI) have consistently reported an increase in central blood volume associated with the cephalad shift in blood volume. This causes an increase in left ventricular end diastolic volume and greater stroke volume during exercise compared to exercise in air at similar metabolic costs. In contrast, the metabolic response, specifically, blood lactate accumulation during exercise combined with HOI has yielded varying results depending on the mode of exercise. At present it appears that during exercise at similar metabolic costs, cycle ergometry exercise augments plasma lactate over treadmill running while HOI reduces the plasma lactate response to cycle ergometry exercise. The interaction between treadmill running and HOI appears less certain...

La presente invention concerne une greffe de cartilage pouvant faciliter la desinfection, le nett... more La presente invention concerne une greffe de cartilage pouvant faciliter la desinfection, le nettoyage, la devitalisation, la recellularisation et l'integration apres implantation. L'invention concerne egalement le nettoyage et la devitalisation de cartilage. Elle concerne en outre des procedes de recellularisation de cartilage et d'implantation de cartilage.

Open Forum Infectious Diseases, 2021

Background Tissue donors are evaluated for communicable disease in order to minimize the risk of ... more Background Tissue donors are evaluated for communicable disease in order to minimize the risk of transmission to recipients. Although there are data suggesting SARS-CoV-2 viremia across a wide spectrum of illness, prevalence in deceased tissue donors and the potential for transplant transmission are unknown. Methods Eight tissue banks participated in a retrospective analysis of samples from eligible deceased tissue donors from Oct 2019 through June 2020, one participant in Canada and the remainder located in the United States. All four Census regions of the continental US and all major racial-ethnic groups were represented. EDTA or sodium citrate plasma aliquots were tested in singlicate with the Research Use Only Procleix SARS-CoV-2 Assay on the Procleix Panther System, which uses transcription-mediated nucleic acid amplification (TMA) technology for detection of the SARS-CoV-2 RNA. Plasma (or if unavailable, serum) aliquots were sent to Grifols for an alternate SARS-CoV-2 nucleic ...

of human dermis using non-denaturing

Journal of Heart Valve Disease, 2004

Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered... more Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered heart valve designs, with the expectation of replicating the anatomic, histological and biomechanical characteristics of semi-lunar valves. The study aim was to evaluate the extent of in-vivo recellularization and the explant pathology findings of a prototype anionic, non-denaturing detergent and endonuclease technique used to decellularize allograft (homograft) valve conduits implanted in the right ventricular outflow tract (RVOT) of sheep, and to identify possible risks associated with tissue-engineered heart valve conduits based on decellularized allograft semilunar valve scaffolds. Valve conduits were decellularized using a solution of N-lauroylsarcosinate and endonucleases, rinsed in lactated Ringers solution, and stored in an antibiotic solution at 4 degrees C until implanted. Explanted valves and unimplanted controls were examined macroscopically, radiographically (for calcificat...

Cell and tissue banking, Jan 29, 2016

In regard to evaluating tissue banking methods used to preserve or otherwise treat (process) soft... more In regard to evaluating tissue banking methods used to preserve or otherwise treat (process) soft allograft tissue, current tests may not be sufficiently sensitive to detect potential damage inflicted before, during, and after processing. Using controlled parameters, we aim to examine the sensitivity of specific biomechanical, electrical, and biological tests in detecting mild damage to collagen. Fresh porcine pulmonary heart valves were treated with an enzyme, collagenase, and incubated using various times. Controls received no incubation. All valves were cryopreserved and stored at -135 °C until being rewarmed for evaluation using biomechanical, permeability, and cell viability tests. Statistically significant time dependent changes in leaflet ultimate stress, (p = 0.006), permeability (p = 0.01), and viability (p ≤ 0.02, four different days of culture) were found between heart valves subjected to 0-15 min of collagenase treatment (ANOVA). However, no statistical significance was ...

BACKGROUND AND AIM OF THE STUDY Biodegradable polymeric materials or extracellular matrix scaffol... more BACKGROUND AND AIM OF THE STUDY Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered heart valve designs, with the expectation of replicating the anatomic, histological and biomechanical characteristics of semi-lunar valves. The study aim was to evaluate the extent of in-vivo recellularization and the explant pathology findings of a prototype anionic, non-denaturing detergent and endonuclease technique used to decellularize allograft (homograft) valve conduits implanted in the right ventricular outflow tract (RVOT) of sheep, and to identify possible risks associated with tissue-engineered heart valve conduits based on decellularized allograft semilunar valve scaffolds. METHODS Valve conduits were decellularized using a solution of N-lauroylsarcosinate and endonucleases, rinsed in lactated Ringers solution, and stored in an antibiotic solution at 4 degrees C until implanted. Explanted valves and unimplanted controls were examined macroscop...

Cardiovascular engineering and technology, Jan 13, 2017

The purpose of this study was to determine the impact of elevated temperature exposure in tissue ... more The purpose of this study was to determine the impact of elevated temperature exposure in tissue banking on soft tissues. A secondary objective was to determine the relative ability of various assays to detect changes in soft tissues due to temperature deviations. Porcine pulmonary heart valve leaflets exposed to 37 °C were compared with those incubated at 52 and 67 °C for 10, 30 and 100 min. The analytical methods consisted of (1) viability assessment using the resazurin assay, (2) collagen content using the Sircol assay, and (3) permeability assessment using an electrical conductivity assay. Additionally, histology and two photon microscopy were used to reveal mechanisms of cell and tissue damage. Viability, collagen content, and permeability all decreased following heat treatment. In terms of statistical significance with respect to treatment temperature, cell viability was most affected (p < 0.0001), followed by permeability (p < 0.0001), and then collagen content (p = 0.1...

Advances in Skin & Wound Care, 2016

The Journal of Heart Valve Disease, Oct 1, 2004

Cryopreserved allograft (homograft) heart valves remain as the standard for ventricular outflow t... more Cryopreserved allograft (homograft) heart valves remain as the standard for ventricular outflow tract reconstruction in infants, children and young adults (1,2). Although the long-term safety and clinical performance of cryopreserved allografts is encouraging (3), their performance characteristics are not ideal in

The Journal of heart valve disease, 2004

Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered... more Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered heart valve designs, with the expectation of replicating the anatomic, histological and biomechanical characteristics of semi-lunar valves. The study aim was to evaluate the extent of in-vivo recellularization and the explant pathology findings of a prototype anionic, non-denaturing detergent and endonuclease technique used to decellularize allograft (homograft) valve conduits implanted in the right ventricular outflow tract (RVOT) of sheep, and to identify possible risks associated with tissue-engineered heart valve conduits based on decellularized allograft semilunar valve scaffolds. Valve conduits were decellularized using a solution of N-lauroylsarcosinate and endonucleases, rinsed in lactated Ringers solution, and stored in an antibiotic solution at 4 degrees C until implanted. Explanted valves and unimplanted controls were examined macroscopically, radiographically (for calcificat...

Fehily/Tissue and Cell Processing, 2012

Cell and Tissue Banking, 2014

Decellularized human dermis has been used for a number of clinical applications including wound h... more Decellularized human dermis has been used for a number of clinical applications including wound healing, soft tissue reconstruction, and sports medicine procedures. A variety of methods exist to prepare this useful class of biomaterial. Here, we describe a decellularization technology (MatrA-CELL Ò) utilizing a non-denaturing anionic detergent, N-Lauroyl sarcosinate, and endonuclease, which was developed to remove potentially immunogenic material while retaining biomechanical properties. Effective decellularization was demonstrated by a residual DNA content of B4 ng/mg of wet weight which represented[97 % DNA removal compared to unprocessed dermis. Two millimeter thick MatrACELL processed human acellular dermal matrix (MH-ADM) exhibited average ultimate tensile load to failure of 635.4 ± 199.9 N and average suture retention strength of 134.9 ± 55.1 N. Using an in vivo mouse skin excisional model, MH-ADM was shown to be biocompatible and capable of supporting cellular and vascular in-growth. Finally, clinical studies of MH-ADM in variety of applications suggest it can be an appropriate scaffold for wound healing, soft tissue reconstruction, and soft tissue augmentation.

Cryopreserved allograft heart valves represent the best solution for a patient with a failing hea... more Cryopreserved allograft heart valves represent the best solution for a patient with a failing heart valve. However, the constituent cells become apoptotic and within months of transplant the heart valve becomes acellular and the recipient's cells do not repopulate the allograft (3, 51). A strategy to prevent this situation would be to minimize or prevent apoptosis from occurring by strategically altering steps during heart valve processing. Recently it has been demonstrated that: 1) Heat shock protein 70 is a negative modulator of the apoptotic cascade; 2) Cells in culture exposed to hypothermic conditions produce heat shock protein 70 upon rewarming; and 3) Glutamine can induce heat shock protein 70 production. The purpose of the current research is to apply these vii TABLE OF CONTENTS Page LIST OF TABLES ix LIST OF FIGURES x Chapter viii 3.18 STATISTICAL ANALYSIS 4. RESULT 4.1 DONOR VARIABLES 4.2 PROTEIN CONCENTRATION OVER TIME 4.3 GLUTAMINE CONCENTRATION 4.4 HEAT SHOCK PROTEIN 70 QUANTITATION ANTIBIOTIC INCUBATION 4.5 HEAT SHOCK PROTEIN 70 QUANTITATION INCUBATION POST-CRYOPRESERVATION 4.6 CYTOCHROME C QUANTITATION CYTOSOLIC ANALYSIS DURING ANTIBIOTIC INCUBATION 4.7 CYTOCHROME C QUANTITATION CYTOSOLIC ANALYSIS POST-CRYOPRESERVATION 4.8 CYTOCHROME C QUANTITATION MITOCHONDRIAL ANALYSIS DURING ANTIBIOTIC INCUBATION 4.9 CYTOCHROME C QUANTITATION MITOCHONDRIAL ANALYSIS POST-CRYOPRESERVATION 4.10 BCL-2 QUANTITATION-PRECRYOPRESERVATION .. .84 4.11BCL-2 QUANTITATION-POSTCRYOPRESERVATION 4.12CASPASE-3 IMMUNOHISTOCHEMISTRY-PRECRYOPRESERVATION 4.13 CASPASE-3 IMMUNOHISTOCHEMISTRY-POST-CYOPRESERVATION 4.14 VISUALIZATION OF APOPTOTIC CELLS-PRECRYOPRESERVATION 109 4.15 VISUALIZATION OF APOPTOTIC CELLS-POST-CRYOPRESERVATION 113 5. DISCUSSION 123 6. CONCLUSIONS AND FUTURE RESEARCH 135 xi 17. Quantitation of mitochondrial cytochrome c in aortic conduit tissue after Cryopreservation 18. Mitochondrial cytochrome c vs. Hsp70 content over time during post-cryopreservation in the 4°C and 4°C+GLN treatment groups 19. Mitochondrial cytochrome c vs. Hsp70 content in the cells post-cryopreservation in the 37°C and 37°C+GLN treatment groups 20. Cytochrome c content in the mitochondria for each treatment group for the duration of the study-disinfection and post-cryopreservation 21. Quantitation of Bcl-2 in aortic conduit tissue during disinfection under various treatment conditions 22. Bcl-2 vs. Hsp70 content over time during disinfection in the 4°C and 4°C+GLN treatment groups 23. Bcl-2 vs. Hsp70 content over time during disinfection in the 37°C and 37°C+GLN treatment groups 24. Quantitation of Bcl-2 in aortic conduit tissue after cryopreservation 25. Bcl-2 vs. Hsp70 content over time post-cryopreservation in the 4°C and 4°C+GLN treatment groups 26. Bcl-2 vs. Hsp70 content in the cells post-cryopreservation in the 37°C and 37°C+GLN treatment groups 27. Quantitation of caspase-3 in aortic conduit tissue during disinfection under various treatment conditions 28. Caspase-3 vs. Hsp70 content in the cells during.disinfection in the 4°C and 4°C+GLN treatment groups 29. Percentage of Caspase-3 positive cells vs. Hsp70 content over time during disinfection in the 37°C and 37°C+GLN treatment groups 30. Quantitation of caspase-3 in aortic conduit tissue after cryopreservation 98 31. Percentage of Caspase-3 positive cells vs. Hsp70 content in the cells post-cryopreservation in the 4°C and 4°C+GLN treatment groups 99 32. Percentage of caspase-3 positive cells vs. Hsp70 content over time post-cryopreservation in the 37°C and 37°C+GLN treatment groups 100 33. Caspase-3 Positive Control 101 34. Caspase-3 Positive Control 102 xii 35. Caspase-3 Negative Control 36. Baseline caspase-3 staining 104 37. Baseline caspase-3 staining 38. Caspase-3 micrograph, 25% positivity 106 39. Caspase-3 micrograph, 25% positivity 107 40. Caspase-3 micrograph, 45% positivity 108 41. Quantitation of TUNEL positive cells in aortic conduit tissue during disinfection under various treatment conditions 110 42. Percentage of TUNEL positive cells vs. Hsp70 content over time during disinfection in the 4°C and 4°C+GLN treatment groups 43. Percentage of TUNEL positive cells vs. Hsp70 content in the cells during disinfection in the 37°C and 37°C+GLN treatment groups 44. Quantitation of TUNEL positive cells in aortic conduit tissue after Cryopreservation 45. Percentage of TUNEL positive cells vs. Hsp70 content in the cells post-cryopreservation in the 4°C and 4°C+GLN treatment groups 46. Percentage of TUNEL positive cells vs. Hsp70 content in the cells post-cryopreservation in the 37°C and 37°C+GLN treatment groups 47. TUNEL Positive Control 118 48. TUNEL Negative Control 119 49. Baseline TUNEL staining 120 50. TUNEL micrograph, 25% positivity 121 51. TUNEL micrograph, 45% positivity 52. Hsp70 Inductive Signals, Hsp70 Gene Activation and HP70 Synthesis 130 53. Multiple Negative Control Points in the Apoptotic Cascade that Hsp70 Modulates 131

Cell and Tissue Banking, Dec 9, 2022

Given the possibility for disease transmission, this study was performed to determine whether the... more Given the possibility for disease transmission, this study was performed to determine whether there is detectable SARS-CoV-2 viral RNA in the blood of deceased tissue donors. A retrospective analysis of blood samples from eligible deceased tissue donors from Oct 2019 through June 2020 was performed. Plasma aliquots were initially tested with a SARS-CoV-2 NAT Assay; positive samples were further tested using an alternate NAT and an antibody assay. The proportion of donors with confirmed RNAemia and 95% confidence intervals were computed. Of donor samples collected in 2019, 894 yielded valid results, with 6 initially positive, none of which confirmed positive by alternate NAT. Of donor samples collected in 2020, 2562 yielded valid initial NAT results, with 21 (0.8%) initially positive.

Cell and Tissue Banking

Given the possibility for disease transmission, this study was performed to determine whether the... more Given the possibility for disease transmission, this study was performed to determine whether there is detectable SARS-CoV-2 viral RNA in the blood of deceased tissue donors. A retrospective analysis of blood samples from eligible deceased tissue donors from Oct 2019 through June 2020 was performed. Plasma aliquots were initially tested with a SARS-CoV-2 NAT Assay; positive samples were further tested using an alternate NAT and an antibody assay. The proportion of donors with confirmed RNAemia and 95% confidence intervals were computed. Of donor samples collected in 2019, 894 yielded valid results, with 6 initially positive, none of which confirmed positive by alternate NAT. Of donor samples collected in 2020, 2562 yielded valid initial NAT results, with 21 (0.8%) initially positive. Among those, 3 were confirmed by alternate NAT, 17 were not confirmed, and 1 had an invalid alternate NAT result. The rate of SARS-CoV-2 RNAemia in deceased tissue donors is approximately 1 per 1000, an...

LACTATE THRESHOLD: THE COMPARISON OF RUNNING ON A LAND TREADMILL VERSUS HEAD-OUT WATER IMMERSION ... more LACTATE THRESHOLD: THE COMPARISON OF RUNNING ON A LAND TREADMILL VERSUS HEAD-OUT WATER IMMERSION TREADMILL RUNNING. Stephanie Jones Zobell Department of Exercise Sciences Master of Science ABSTRACT Introduction. Exercise and head-out water immersion (HOI) have consistently reported an increase in central blood volume associated with the cephalad shift in blood volume. This causes an increase in left ventricular end diastolic volume and greater stroke volume during exercise compared to exercise in air at similar metabolic costs. In contrast, the metabolic response, specifically, blood lactate accumulation during exercise combined with HOI has yielded varying results depending on the mode of exercise. At present it appears that during exercise at similar metabolic costs, cycle ergometry exercise augments plasma lactate over treadmill running while HOI reduces the plasma lactate response to cycle ergometry exercise. The interaction between treadmill running and HOI appears less certain...

La presente invention concerne une greffe de cartilage pouvant faciliter la desinfection, le nett... more La presente invention concerne une greffe de cartilage pouvant faciliter la desinfection, le nettoyage, la devitalisation, la recellularisation et l'integration apres implantation. L'invention concerne egalement le nettoyage et la devitalisation de cartilage. Elle concerne en outre des procedes de recellularisation de cartilage et d'implantation de cartilage.

Open Forum Infectious Diseases, 2021

Background Tissue donors are evaluated for communicable disease in order to minimize the risk of ... more Background Tissue donors are evaluated for communicable disease in order to minimize the risk of transmission to recipients. Although there are data suggesting SARS-CoV-2 viremia across a wide spectrum of illness, prevalence in deceased tissue donors and the potential for transplant transmission are unknown. Methods Eight tissue banks participated in a retrospective analysis of samples from eligible deceased tissue donors from Oct 2019 through June 2020, one participant in Canada and the remainder located in the United States. All four Census regions of the continental US and all major racial-ethnic groups were represented. EDTA or sodium citrate plasma aliquots were tested in singlicate with the Research Use Only Procleix SARS-CoV-2 Assay on the Procleix Panther System, which uses transcription-mediated nucleic acid amplification (TMA) technology for detection of the SARS-CoV-2 RNA. Plasma (or if unavailable, serum) aliquots were sent to Grifols for an alternate SARS-CoV-2 nucleic ...

of human dermis using non-denaturing

Journal of Heart Valve Disease, 2004

Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered... more Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered heart valve designs, with the expectation of replicating the anatomic, histological and biomechanical characteristics of semi-lunar valves. The study aim was to evaluate the extent of in-vivo recellularization and the explant pathology findings of a prototype anionic, non-denaturing detergent and endonuclease technique used to decellularize allograft (homograft) valve conduits implanted in the right ventricular outflow tract (RVOT) of sheep, and to identify possible risks associated with tissue-engineered heart valve conduits based on decellularized allograft semilunar valve scaffolds. Valve conduits were decellularized using a solution of N-lauroylsarcosinate and endonucleases, rinsed in lactated Ringers solution, and stored in an antibiotic solution at 4 degrees C until implanted. Explanted valves and unimplanted controls were examined macroscopically, radiographically (for calcificat...

Cell and tissue banking, Jan 29, 2016

In regard to evaluating tissue banking methods used to preserve or otherwise treat (process) soft... more In regard to evaluating tissue banking methods used to preserve or otherwise treat (process) soft allograft tissue, current tests may not be sufficiently sensitive to detect potential damage inflicted before, during, and after processing. Using controlled parameters, we aim to examine the sensitivity of specific biomechanical, electrical, and biological tests in detecting mild damage to collagen. Fresh porcine pulmonary heart valves were treated with an enzyme, collagenase, and incubated using various times. Controls received no incubation. All valves were cryopreserved and stored at -135 °C until being rewarmed for evaluation using biomechanical, permeability, and cell viability tests. Statistically significant time dependent changes in leaflet ultimate stress, (p = 0.006), permeability (p = 0.01), and viability (p ≤ 0.02, four different days of culture) were found between heart valves subjected to 0-15 min of collagenase treatment (ANOVA). However, no statistical significance was ...

BACKGROUND AND AIM OF THE STUDY Biodegradable polymeric materials or extracellular matrix scaffol... more BACKGROUND AND AIM OF THE STUDY Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered heart valve designs, with the expectation of replicating the anatomic, histological and biomechanical characteristics of semi-lunar valves. The study aim was to evaluate the extent of in-vivo recellularization and the explant pathology findings of a prototype anionic, non-denaturing detergent and endonuclease technique used to decellularize allograft (homograft) valve conduits implanted in the right ventricular outflow tract (RVOT) of sheep, and to identify possible risks associated with tissue-engineered heart valve conduits based on decellularized allograft semilunar valve scaffolds. METHODS Valve conduits were decellularized using a solution of N-lauroylsarcosinate and endonucleases, rinsed in lactated Ringers solution, and stored in an antibiotic solution at 4 degrees C until implanted. Explanted valves and unimplanted controls were examined macroscop...

Cardiovascular engineering and technology, Jan 13, 2017

The purpose of this study was to determine the impact of elevated temperature exposure in tissue ... more The purpose of this study was to determine the impact of elevated temperature exposure in tissue banking on soft tissues. A secondary objective was to determine the relative ability of various assays to detect changes in soft tissues due to temperature deviations. Porcine pulmonary heart valve leaflets exposed to 37 °C were compared with those incubated at 52 and 67 °C for 10, 30 and 100 min. The analytical methods consisted of (1) viability assessment using the resazurin assay, (2) collagen content using the Sircol assay, and (3) permeability assessment using an electrical conductivity assay. Additionally, histology and two photon microscopy were used to reveal mechanisms of cell and tissue damage. Viability, collagen content, and permeability all decreased following heat treatment. In terms of statistical significance with respect to treatment temperature, cell viability was most affected (p < 0.0001), followed by permeability (p < 0.0001), and then collagen content (p = 0.1...

Advances in Skin & Wound Care, 2016

The Journal of Heart Valve Disease, Oct 1, 2004

Cryopreserved allograft (homograft) heart valves remain as the standard for ventricular outflow t... more Cryopreserved allograft (homograft) heart valves remain as the standard for ventricular outflow tract reconstruction in infants, children and young adults (1,2). Although the long-term safety and clinical performance of cryopreserved allografts is encouraging (3), their performance characteristics are not ideal in

The Journal of heart valve disease, 2004

Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered... more Biodegradable polymeric materials or extracellular matrix scaffolds are used in tissue-engineered heart valve designs, with the expectation of replicating the anatomic, histological and biomechanical characteristics of semi-lunar valves. The study aim was to evaluate the extent of in-vivo recellularization and the explant pathology findings of a prototype anionic, non-denaturing detergent and endonuclease technique used to decellularize allograft (homograft) valve conduits implanted in the right ventricular outflow tract (RVOT) of sheep, and to identify possible risks associated with tissue-engineered heart valve conduits based on decellularized allograft semilunar valve scaffolds. Valve conduits were decellularized using a solution of N-lauroylsarcosinate and endonucleases, rinsed in lactated Ringers solution, and stored in an antibiotic solution at 4 degrees C until implanted. Explanted valves and unimplanted controls were examined macroscopically, radiographically (for calcificat...

Fehily/Tissue and Cell Processing, 2012

Cell and Tissue Banking, 2014

Decellularized human dermis has been used for a number of clinical applications including wound h... more Decellularized human dermis has been used for a number of clinical applications including wound healing, soft tissue reconstruction, and sports medicine procedures. A variety of methods exist to prepare this useful class of biomaterial. Here, we describe a decellularization technology (MatrA-CELL Ò) utilizing a non-denaturing anionic detergent, N-Lauroyl sarcosinate, and endonuclease, which was developed to remove potentially immunogenic material while retaining biomechanical properties. Effective decellularization was demonstrated by a residual DNA content of B4 ng/mg of wet weight which represented[97 % DNA removal compared to unprocessed dermis. Two millimeter thick MatrACELL processed human acellular dermal matrix (MH-ADM) exhibited average ultimate tensile load to failure of 635.4 ± 199.9 N and average suture retention strength of 134.9 ± 55.1 N. Using an in vivo mouse skin excisional model, MH-ADM was shown to be biocompatible and capable of supporting cellular and vascular in-growth. Finally, clinical studies of MH-ADM in variety of applications suggest it can be an appropriate scaffold for wound healing, soft tissue reconstruction, and soft tissue augmentation.