Kevin Lye - Academia.edu (original) (raw)
Papers by Kevin Lye
Physiological Genomics, 2004
Enterochromaffin-like (ECL) cell hyperplasia and then irreversible neoplasia can be generated in ... more Enterochromaffin-like (ECL) cell hyperplasia and then irreversible neoplasia can be generated in the African rodent Mastomys natalensis using the H2 receptor blocker, loxtidine, for 8–16 wk. We used a GeneChip approach complemented by standard technologies to identify gene expression alterations in the gastric mucosa during gastrin-mediated ECL cell transformation. Gastric mucosa (mucosal scrapping) and ECL cell-enriched fractions were obtained from untreated Mastomys (controls) and from animals treated with loxtidine for 8 wk (hyperplasia). Tumor ECL cells were obtained by hand-dissection of gastric ECL cell nodules from animals treated with loxtidine for >16 wk and from a spontaneously developed ECL cell tumor. RNA was isolated, examined on rat U34A GeneChips, and comparison analysis was performed to identify altered gene expression. Alterations in gene expressions were examined further by immunohistochemistry, quantitative RT-PCR (Q-RT-PCR), sequencing and Western blot. GeneSp...
Tissue engineering. Part C, Methods, Jan 28, 2017
Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clini... more Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clinical applications. The current study evaluated a point of care (POC) technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived stromal vascular fraction cells to be used in the fabrication of a tissue engineered vascular graft in the operating room. A total of 7 patients were enrolled in this FDA registered Investigational Device Exemption clinical trial and received femoral to tibial expanded polytetrafluoroethylene (ePTFE) bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on 5 patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe was 70 minutes. The SVF cell population was evaluated for cell yield, endotoxin levels a...
Hawaii Medical Journal, Apr 1, 2009
Purpose: Breast reconstruction with expander/implants is generally discouraged in patients who ha... more Purpose: Breast reconstruction with expander/implants is generally discouraged in patients who have undergone radiation therapy. However, not every patient treated with radiation develops sequelae severe enough to preclude the use of prostheses. To date, there have been no studies that have established criteria for selecting which patients may still be considered for expander/implant reconstruction. We present a series of 27 patients--the largest of its kind to date--all of whom underwent bilateral mastectomies, radiation therapy to only one chest wall, and delayed reconstruction with submuscular expander/implants. The aesthetic outcomes of the irradiated and the non-irradiated breasts were compared, and a classification of post-radiation skin changes was devised for selecting candidates for expander/implant reconstruction. Methods: Patient records were reviewed to identify those who had undergone bilateral mastectomies, radiation treatment to only one chest wall, and delayed expander/implant reconstructions of both breasts. Twenty-seven patients were identified who met our inclusion criteria. Early post-radiation skin changes were classified as "moderate" or "severe," while aesthetic assessments were classified as "good," "acceptable" or "poor." Results: Irradiated chest walls with moderate skin changes and absent induration have aesthetic outcomes comparable to the nonirradiated chest walls (p > 0.50). In contrast, patients who develop induration or severe post-radiation skin changes have a greater rate of modified Baker class IV capsular contracture and poor results that range from 75% to 100% of reconstructed breasts. Conclusions: A history of chest wall radiation should not itself exclude patients from receiving expander/implant reconstruction. Patients who develop neither severe skin changes nor induration may still be considered for prostheses.
The Surgeon Journal of the Royal Colleges of Surgeons of Edinburgh and Ireland, Jul 1, 2003
Journal of Clinical Gastroenterology, Apr 30, 2004
The European Journal of Surgery Acta Chirurgica, Feb 1, 2002
Plastic and Reconstructive Surgery, 2007
Journal of clinical gastroenterology
Although Galen first described esophagitis almost 2000 years ago, its relation to acid was only r... more Although Galen first described esophagitis almost 2000 years ago, its relation to acid was only recognized in the 19th century by Rokitansky. Considerably more interest in the symptoms and complications of esophagitis has been evident over the last century, as gastroesophageal reflux disease displaced peptic ulceration and became the principal acid-related disease of our times. Of particular interest has been the recognition of the clinical significance of the previously overlooked extraesophageal manifestations of the disease such as laryngitis, asthma, and sleep disturbance. The evolution of highly effective medical therapy has over the last decade drastically reduced the need for surgical intervention for control of symptoms except under select conditions, especially volume-related reflux and children with refractory symptoms. The proton pump inhibitor class of drugs is indisputably the most effective overall form of management, while individual proton pump inhibitors appear to b...
Gastrointestinal Endoscopy Clinics of North America, 2003
Plastic and Reconstructive Surgery, 2008
Tissue engineering. Part C, Methods, Jan 28, 2017
Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clini... more Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clinical applications. The current study evaluated a point of care (POC) technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived stromal vascular fraction cells to be used in the fabrication of a tissue engineered vascular graft in the operating room. A total of 7 patients were enrolled in this FDA registered Investigational Device Exemption clinical trial and received femoral to tibial expanded polytetrafluoroethylene (ePTFE) bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on 5 patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe was 70 minutes. The SVF cell population was evaluated for cell yield, endotoxin levels a...
Tissue engineering. Part C, Methods, Jan 28, 2017
Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clini... more Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clinical applications. The current study evaluated a point of care (POC) technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived stromal vascular fraction cells to be used in the fabrication of a tissue engineered vascular graft in the operating room. A total of 7 patients were enrolled in this FDA registered Investigational Device Exemption clinical trial and received femoral to tibial expanded polytetrafluoroethylene (ePTFE) bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on 5 patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe was 70 minutes. The SVF cell population was evaluated for cell yield, endotoxin levels a...
Http Dx Doi Org 10 1089 Ten Tea 2012 0318, Apr 26, 2013
We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal v... more We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal vascular fraction cells, and the subsequent deposition of these cells onto the luminal surface of an expanded polytetrafluoroethylene (ePTFE) vascular graft for use as a bypass graft. The hypothesis evaluated was that an instrument requiring minimal user interface will provide a therapeutic dose of cells to improve the patency of synthetic vascular grafts in an autologous animal model of graft patency. The stromal vascular fraction (SVF) cells were isolated using an automated adipose tissue processing and cell isolation system and cells sodded onto the surface of an ePTFE vascular graft. Control grafts, used off-the-shelf without cell treatment were used as a control to assess patency effects. Each animal received a control, untreated graft implanted in one carotid artery, and the cell-treated graft implanted in the carotid artery on the contralateral side. The grafts were implanted for 6 months utilizing 12 animals. Results indicate a fully automated adipose tissue processing system will consistently produce functional autologous cells for immediate use in the operating room. Cell-sodded polymeric grafts exhibited improved patency compared to control grafts after 6 month implantation in the canine carotid artery model.
Stem Cells and Cloning: Advances and Applications, 2015
Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In th... more Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In this study, we present our findings on the potential application of adipose-derived stem cells (ASCs) as well as induced cardiac-like progenitors (iCPs) derived from ASCs for the treatment of myocardial infarction. Human bone marrow (BM)-derived stem cells, ASCs, and iCPs generated from ASCs using three defined cardiac lineage transcription factors were assessed in an immune-compromised mouse myocardial infarction model. Analysis of iCP prior to transplant confirmed changes in gene and protein expression consistent with a cardiac phenotype. Endpoint analysis was performed 1 month posttransplant. Significantly increased endpoint fractional shortening, as well as reduction in the infarct area at risk, was observed in recipients of iCPs as compared to the other recipient cohorts. Both recipients of iCPs and ASCs presented higher myocardial capillary densities than either recipients of BM-derived stem cells or the control cohort. Furthermore, mice receiving iCPs had a significantly higher cardiac retention of transplanted cells than all other groups. Overall, iCPs generated from ASCs outperform BM-derived stem cells and ASCs in facilitating recovery from induced myocardial infarction in mice.
Tissue Engineering Part A, 2013
We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal v... more We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal vascular fraction cells, and the subsequent deposition of these cells onto the luminal surface of an expanded polytetrafluoroethylene (ePTFE) vascular graft for use as a bypass graft. The hypothesis evaluated was that an instrument requiring minimal user interface will provide a therapeutic dose of cells to improve the patency of synthetic vascular grafts in an autologous animal model of graft patency. The stromal vascular fraction (SVF) cells were isolated using an automated adipose tissue processing and cell isolation system and cells sodded onto the surface of an ePTFE vascular graft. Control grafts, used off-the-shelf without cell treatment were used as a control to assess patency effects. Each animal received a control, untreated graft implanted in one carotid artery, and the cell-treated graft implanted in the carotid artery on the contralateral side. The grafts were implanted for 6 months utilizing 12 animals. Results indicate a fully automated adipose tissue processing system will consistently produce functional autologous cells for immediate use in the operating room. Cell-sodded polymeric grafts exhibited improved patency compared to control grafts after 6 month implantation in the canine carotid artery model.
Bailliere S Best Practice Research Clinical Gastroenterology, 2002
Bailliere S Best Practice Research Clinical Gastroenterology, Dec 31, 2002
resolution of a disease aecting a speci®c organ system. In this fashion, a time sensitive trainin... more resolution of a disease aecting a speci®c organ system. In this fashion, a time sensitive training programme producing educationally pre-focused physicians can be implemented to deliver time eective care in a cost contained environment with maximization of expertise and comprehensive interdisciplinary integration of knowledge, experience and skill (cluster care module). As such, digestive surgery itself should cease to be regarded as an end in itself or separate entity, but rather as representative of one facet in the delivery of a multifaceted integrated health care modality focused on the digestive tract.
J Amer Coll Surgeons, 2002
Temporary abdominal closure in damage-control celiotomy has become a common procedure, frequently... more Temporary abdominal closure in damage-control celiotomy has become a common procedure, frequently leading to large, full-thickness abdominal wall defects. Several surgical techniques have been used to close the ensuing defects, including a spectrum of muscle and pedicle grafts. 1-4 The Suture Tension Adjustment Reel (STAR, Closure Systems, LLC, Boston, MA) system was originally introduced to assist in closure of calf fasciotomy defects by applying constant and progressive tension to wound edges. We adapted the STAR system to aid in closure of three large, full-thickness abdominal wall defects by placing the winding, ratcheting device over a suture loop extending through the full thickness of the abdominal wall.
Physiological Genomics, 2004
Enterochromaffin-like (ECL) cell hyperplasia and then irreversible neoplasia can be generated in ... more Enterochromaffin-like (ECL) cell hyperplasia and then irreversible neoplasia can be generated in the African rodent Mastomys natalensis using the H2 receptor blocker, loxtidine, for 8–16 wk. We used a GeneChip approach complemented by standard technologies to identify gene expression alterations in the gastric mucosa during gastrin-mediated ECL cell transformation. Gastric mucosa (mucosal scrapping) and ECL cell-enriched fractions were obtained from untreated Mastomys (controls) and from animals treated with loxtidine for 8 wk (hyperplasia). Tumor ECL cells were obtained by hand-dissection of gastric ECL cell nodules from animals treated with loxtidine for >16 wk and from a spontaneously developed ECL cell tumor. RNA was isolated, examined on rat U34A GeneChips, and comparison analysis was performed to identify altered gene expression. Alterations in gene expressions were examined further by immunohistochemistry, quantitative RT-PCR (Q-RT-PCR), sequencing and Western blot. GeneSp...
Tissue engineering. Part C, Methods, Jan 28, 2017
Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clini... more Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clinical applications. The current study evaluated a point of care (POC) technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived stromal vascular fraction cells to be used in the fabrication of a tissue engineered vascular graft in the operating room. A total of 7 patients were enrolled in this FDA registered Investigational Device Exemption clinical trial and received femoral to tibial expanded polytetrafluoroethylene (ePTFE) bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on 5 patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe was 70 minutes. The SVF cell population was evaluated for cell yield, endotoxin levels a...
Hawaii Medical Journal, Apr 1, 2009
Purpose: Breast reconstruction with expander/implants is generally discouraged in patients who ha... more Purpose: Breast reconstruction with expander/implants is generally discouraged in patients who have undergone radiation therapy. However, not every patient treated with radiation develops sequelae severe enough to preclude the use of prostheses. To date, there have been no studies that have established criteria for selecting which patients may still be considered for expander/implant reconstruction. We present a series of 27 patients--the largest of its kind to date--all of whom underwent bilateral mastectomies, radiation therapy to only one chest wall, and delayed reconstruction with submuscular expander/implants. The aesthetic outcomes of the irradiated and the non-irradiated breasts were compared, and a classification of post-radiation skin changes was devised for selecting candidates for expander/implant reconstruction. Methods: Patient records were reviewed to identify those who had undergone bilateral mastectomies, radiation treatment to only one chest wall, and delayed expander/implant reconstructions of both breasts. Twenty-seven patients were identified who met our inclusion criteria. Early post-radiation skin changes were classified as "moderate" or "severe," while aesthetic assessments were classified as "good," "acceptable" or "poor." Results: Irradiated chest walls with moderate skin changes and absent induration have aesthetic outcomes comparable to the nonirradiated chest walls (p > 0.50). In contrast, patients who develop induration or severe post-radiation skin changes have a greater rate of modified Baker class IV capsular contracture and poor results that range from 75% to 100% of reconstructed breasts. Conclusions: A history of chest wall radiation should not itself exclude patients from receiving expander/implant reconstruction. Patients who develop neither severe skin changes nor induration may still be considered for prostheses.
The Surgeon Journal of the Royal Colleges of Surgeons of Edinburgh and Ireland, Jul 1, 2003
Journal of Clinical Gastroenterology, Apr 30, 2004
The European Journal of Surgery Acta Chirurgica, Feb 1, 2002
Plastic and Reconstructive Surgery, 2007
Journal of clinical gastroenterology
Although Galen first described esophagitis almost 2000 years ago, its relation to acid was only r... more Although Galen first described esophagitis almost 2000 years ago, its relation to acid was only recognized in the 19th century by Rokitansky. Considerably more interest in the symptoms and complications of esophagitis has been evident over the last century, as gastroesophageal reflux disease displaced peptic ulceration and became the principal acid-related disease of our times. Of particular interest has been the recognition of the clinical significance of the previously overlooked extraesophageal manifestations of the disease such as laryngitis, asthma, and sleep disturbance. The evolution of highly effective medical therapy has over the last decade drastically reduced the need for surgical intervention for control of symptoms except under select conditions, especially volume-related reflux and children with refractory symptoms. The proton pump inhibitor class of drugs is indisputably the most effective overall form of management, while individual proton pump inhibitors appear to b...
Gastrointestinal Endoscopy Clinics of North America, 2003
Plastic and Reconstructive Surgery, 2008
Tissue engineering. Part C, Methods, Jan 28, 2017
Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clini... more Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clinical applications. The current study evaluated a point of care (POC) technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived stromal vascular fraction cells to be used in the fabrication of a tissue engineered vascular graft in the operating room. A total of 7 patients were enrolled in this FDA registered Investigational Device Exemption clinical trial and received femoral to tibial expanded polytetrafluoroethylene (ePTFE) bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on 5 patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe was 70 minutes. The SVF cell population was evaluated for cell yield, endotoxin levels a...
Tissue engineering. Part C, Methods, Jan 28, 2017
Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clini... more Adipose-derived stromal vascular fraction cell populations are being evaluated for numerous clinical applications. The current study evaluated a point of care (POC) technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived stromal vascular fraction cells to be used in the fabrication of a tissue engineered vascular graft in the operating room. A total of 7 patients were enrolled in this FDA registered Investigational Device Exemption clinical trial and received femoral to tibial expanded polytetrafluoroethylene (ePTFE) bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on 5 patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe was 70 minutes. The SVF cell population was evaluated for cell yield, endotoxin levels a...
Http Dx Doi Org 10 1089 Ten Tea 2012 0318, Apr 26, 2013
We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal v... more We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal vascular fraction cells, and the subsequent deposition of these cells onto the luminal surface of an expanded polytetrafluoroethylene (ePTFE) vascular graft for use as a bypass graft. The hypothesis evaluated was that an instrument requiring minimal user interface will provide a therapeutic dose of cells to improve the patency of synthetic vascular grafts in an autologous animal model of graft patency. The stromal vascular fraction (SVF) cells were isolated using an automated adipose tissue processing and cell isolation system and cells sodded onto the surface of an ePTFE vascular graft. Control grafts, used off-the-shelf without cell treatment were used as a control to assess patency effects. Each animal received a control, untreated graft implanted in one carotid artery, and the cell-treated graft implanted in the carotid artery on the contralateral side. The grafts were implanted for 6 months utilizing 12 animals. Results indicate a fully automated adipose tissue processing system will consistently produce functional autologous cells for immediate use in the operating room. Cell-sodded polymeric grafts exhibited improved patency compared to control grafts after 6 month implantation in the canine carotid artery model.
Stem Cells and Cloning: Advances and Applications, 2015
Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In th... more Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In this study, we present our findings on the potential application of adipose-derived stem cells (ASCs) as well as induced cardiac-like progenitors (iCPs) derived from ASCs for the treatment of myocardial infarction. Human bone marrow (BM)-derived stem cells, ASCs, and iCPs generated from ASCs using three defined cardiac lineage transcription factors were assessed in an immune-compromised mouse myocardial infarction model. Analysis of iCP prior to transplant confirmed changes in gene and protein expression consistent with a cardiac phenotype. Endpoint analysis was performed 1 month posttransplant. Significantly increased endpoint fractional shortening, as well as reduction in the infarct area at risk, was observed in recipients of iCPs as compared to the other recipient cohorts. Both recipients of iCPs and ASCs presented higher myocardial capillary densities than either recipients of BM-derived stem cells or the control cohort. Furthermore, mice receiving iCPs had a significantly higher cardiac retention of transplanted cells than all other groups. Overall, iCPs generated from ASCs outperform BM-derived stem cells and ASCs in facilitating recovery from induced myocardial infarction in mice.
Tissue Engineering Part A, 2013
We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal v... more We evaluated the use of an automated, point-of-care instrument to derive canine adipose stromal vascular fraction cells, and the subsequent deposition of these cells onto the luminal surface of an expanded polytetrafluoroethylene (ePTFE) vascular graft for use as a bypass graft. The hypothesis evaluated was that an instrument requiring minimal user interface will provide a therapeutic dose of cells to improve the patency of synthetic vascular grafts in an autologous animal model of graft patency. The stromal vascular fraction (SVF) cells were isolated using an automated adipose tissue processing and cell isolation system and cells sodded onto the surface of an ePTFE vascular graft. Control grafts, used off-the-shelf without cell treatment were used as a control to assess patency effects. Each animal received a control, untreated graft implanted in one carotid artery, and the cell-treated graft implanted in the carotid artery on the contralateral side. The grafts were implanted for 6 months utilizing 12 animals. Results indicate a fully automated adipose tissue processing system will consistently produce functional autologous cells for immediate use in the operating room. Cell-sodded polymeric grafts exhibited improved patency compared to control grafts after 6 month implantation in the canine carotid artery model.
Bailliere S Best Practice Research Clinical Gastroenterology, 2002
Bailliere S Best Practice Research Clinical Gastroenterology, Dec 31, 2002
resolution of a disease aecting a speci®c organ system. In this fashion, a time sensitive trainin... more resolution of a disease aecting a speci®c organ system. In this fashion, a time sensitive training programme producing educationally pre-focused physicians can be implemented to deliver time eective care in a cost contained environment with maximization of expertise and comprehensive interdisciplinary integration of knowledge, experience and skill (cluster care module). As such, digestive surgery itself should cease to be regarded as an end in itself or separate entity, but rather as representative of one facet in the delivery of a multifaceted integrated health care modality focused on the digestive tract.
J Amer Coll Surgeons, 2002
Temporary abdominal closure in damage-control celiotomy has become a common procedure, frequently... more Temporary abdominal closure in damage-control celiotomy has become a common procedure, frequently leading to large, full-thickness abdominal wall defects. Several surgical techniques have been used to close the ensuing defects, including a spectrum of muscle and pedicle grafts. 1-4 The Suture Tension Adjustment Reel (STAR, Closure Systems, LLC, Boston, MA) system was originally introduced to assist in closure of calf fasciotomy defects by applying constant and progressive tension to wound edges. We adapted the STAR system to aid in closure of three large, full-thickness abdominal wall defects by placing the winding, ratcheting device over a suture loop extending through the full thickness of the abdominal wall.