Frank Dor - Academia.edu (original) (raw)
Papers by Frank Dor
BMJ open, 2015
Delayed graft function due to ischaemia-reperfusion injury is a frequent complication in deceased... more Delayed graft function due to ischaemia-reperfusion injury is a frequent complication in deceased donor renal transplantation. Experimental evidence indicates that remote ischaemic conditioning (RIC) provides systemic protection against ischaemia-reperfusion injury in various tissues. 'Remote ischaemic conditioning in renal transplantation-effect on immediate and extended kidney graft function' (the CONTEXT study) is an investigator initiated, multicentre, randomised controlled trial investigating whether RIC of the leg of the recipient improves short and long-term graft function following deceased donor kidney transplantation. The study will include 200 kidney transplant recipients of organ donation after brain death and 20 kidney transplant recipients of organ donation after circulatory death. Participants are randomised in a 1:1 design to RIC or sham-RIC (control). RIC consists of four cycles of 5 min occlusion of the thigh by a tourniquet inflated to 250 mm Hg, separated...
BMC Medicine, 2015
Whether overweight or obese end stage renal disease (ESRD) patients are suitable for renal transp... more Whether overweight or obese end stage renal disease (ESRD) patients are suitable for renal transplantation (RT) is often debated. The objective of this review and meta-analysis was to systematically investigate the outcome of low versus high BMI recipients after RT. Comprehensive searches were conducted in MEDLINE OvidSP, Web of Science, Google Scholar, Embase, and CENTRAL (the Cochrane Library 2014, issue 8). We reviewed four major guidelines that are available regarding (potential) RT recipients. The methodology was in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and written based on the PRISMA statement. The quality assessment of studies was performed by using the GRADE tool. A meta-analysis was performed using Review Manager 5.3. Random-effects models were used. After identifying 5,526 studies addressing this topic, 56 studies were included. We extracted data for 37 outcome measures (including data of more than 209,000 RT recipients), of which 26 could be meta-analysed. The following outcome measures demonstrated significant differences in favour of low BMI (<30) recipients: mortality (RR = 1.52), delayed graft function (RR = 1.52), acute rejection (RR = 1.17), 1-, 2-, and 3-year graft survival (RR = 0.97, 0.95, and 0.97), 1-, 2-, and 3-year patient survival (RR = 0.99, 0.99, and 0.99), wound infection and dehiscence (RR = 3.13 and 4.85), NODAT (RR = 2.24), length of hospital stay (2.31 days), operation duration (0.77 hours), hypertension (RR = 1.35), and incisional hernia (RR = 2.72). However, patient survival expressed in hazard ratios was in significant favour of high BMI recipients. Differences in other outcome parameters were not significant. Several of the pooled outcome measurements show significant benefits for 'low' BMI (<30) recipients. Therefore, we postulate that ESRD patients with a BMI >30 preferably should lose weight prior to RT. If this cannot be achieved with common measures, in morbidly obese RT candidates, bariatric surgery could be considered.
Transplant international : official journal of the European Society for Organ Transplantation, 2015
The aim of this study was to evaluate the role of ureteral length on urological complications. Da... more The aim of this study was to evaluate the role of ureteral length on urological complications. Data were retrospective collected from the INEX-trial database, a RCT to compare the intravesical to the extravesical ureteroneocystostomy. Ureteral length was measured in 198 recipients and used to divide recipients into three categories based on interquartile ranges: short (≤8.5 cm), medium (8.6-10.9 cm) and long ureters (≥11 cm). Urological complications were defined as the number of percutaneous nephrostomy placements (PCN). Fifty recipients fell into the short, 98 into the medium and 50 recipients into the long ureter category. Median follow-up was 26 (range 2-45) months. There was no significant difference in number of PCN placements between the categories. There were 9 (18%) PCN placements in the short ureter category, 21 (20%) in medium ureter category and 10 (21%) in the long ureter category, P = 0.886. Risk factor analysis for gender, arterial multiplicity and type of ureteroneoc...
PLOS ONE, 2015
Preoperative fasting and dietary restriction offer robust protection against renal ischemia/ repe... more Preoperative fasting and dietary restriction offer robust protection against renal ischemia/ reperfusion injury (I/RI) in mice. We recently showed that Mannan-binding lectin (MBL), the initiator of the lectin pathway of complement activation, plays a pivotal role in renal I/RI. Based on these findings, we investigated the effect of short-term DR (30% reduction of total food intake) or three days of water only fasting on MBL in 10-12 weeks old male C57/Bl6 mice. Both dietary regimens significantly reduce the circulating levels of MBL as well as its mRNA expression in liver, the sole production site of MBL. Reconstitution of MBL abolished the protection afforded by dietary restriction, whereas in the fasting group the protection persisted. These data show that modulation of MBL is involved in the protection against renal I/RI induced by dietary restriction, and suggest that the mechanisms of protection induced by dietary restriction and fasting may be different.
American Journal of Transplantation
The aim of this study is to review the surgical outcome of kidney retransplantation in the ipsila... more The aim of this study is to review the surgical outcome of kidney retransplantation in the ipsilateral iliac fossa in comparison to first kidney transplants. The database was screened for retransplantations between 1995 and 2013. Each study patient was matched with 3 patients with a first kidney transplantation. Just for graft and patient survival analyses, we added an extra control group including all patients receiving a second transplantation in the contralateral iliac fossa. We identified 99 patients who received a retransplantation in the ipsilateral iliac fossa. There was significantly more blood loss and longer operative time in the retransplantation group. The rate of vascular complications and graft nephrectomies within 1 year was significantly higher in the study group. The graft survival rates at 1 year and 3, 5, and 10 years were 76%, 67%, 61%, and 47% in the study group versus 94%, 88%, 77%, and 67% (p < 0.001) in the first control group versus 91%, 86%, 78%, and 57%...
Current Opinion in Organ Transplantation, 2003
ABSTRACT
Obesity, 2015
Brown adipose tissue (BAT) can generate heat by burning fatty acids, a process mediated by uncoup... more Brown adipose tissue (BAT) can generate heat by burning fatty acids, a process mediated by uncoupling protein 1 (UCP1). White adipose tissue (WAT) depots can gain BAT-like properties, and various studies have suggested that females have more active BAT or BAT-like WAT. We studied sex differences in BAT-like properties of human perirenal adipose tissue. Perirenal and subcutaneous adipose tissue was obtained from 20 male and 24 female healthy live kidney donors. Mesenchymal stem cells (MSCs), adipocyte precursor cells, were isolated from these depots to study whether intrinsic factors control BAT-like properties of the adipose tissue depots. When average outside temperature a week before harvesting was below 11°C, brown-like adipocytes expressing UCP1 were present in perirenal adipose tissue of women, but not of men. MSCs derived from perirenal adipose tissue expressed significantly more UCP1 when from female origin compared to male origin (P = 0.009). However, UCP1 protein content and oxygen consumption rate did not differ between adipocytes derived from male and female perirenal MSCs. Female perirenal adipose tissue has a higher potency to gain BAT-like properties than male perirenal adipose tissue. The degree of gaining BAT-like properties depends on sex-specific intrinsic factors and environmental triggers such as temperature.
Journal of Transplantation, 2015
Transplantation, Jan 8, 2015
With the recent transposition of Directive 2010/53/EU into the transplant regulation of EU Member... more With the recent transposition of Directive 2010/53/EU into the transplant regulation of EU Member States, the time is right to have a closer look at its implications for living organ donation practice. We first discuss the relevance of the Action Plan which forms the basis for the policy of the European Commission in the field of organ donation and transplantation. We then analyze the impact of Directive 2010/53/EU which was adopted to support the implementation of the Priority Actions set out in the Action Plan. We more specifically focus on the obligations of transplant centers engaged in living organ donation and highlight their significance for clinical practice. Finally, we point out some strengths and weaknesses of the Directive in addressing living organ donation.
Transplantation, Jan 15, 2014
Informed consent in live donor nephrectomy is a topic of great interest. Safety and transparency ... more Informed consent in live donor nephrectomy is a topic of great interest. Safety and transparency are key items increasingly getting more attention from media and healthcare inspection. Because live donors are not patients, but healthy individuals undergoing elective interventions, they justly insist on optimal conditions and guaranteed safety. Although transplant professionals agree that consent should be voluntary, free of coercion, and fully informed, there is no consensus on which information should be provided, and how the donors' comprehension should be ascertained. Comprehensive searches were conducted in Embase, Medline OvidSP, Web-of-Science, PubMed, CENTRAL (The Cochrane Library 2014, issue 1) and Google Scholar, evaluating the informed consent procedure for live kidney donation. The methodology was in accordance with the Cochrane Handbook for Interventional Systematic Reviews and written based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (P...
Frontiers in immunology, 2013
Xenotransplantation, 2004
The Journal of heart valve disease, 2002
Human valve allografts are commonly used in cardiac surgery for congenital and acquired valve dis... more Human valve allografts are commonly used in cardiac surgery for congenital and acquired valve diseases. Particularly in the pediatric population, these allografts are prone to fail in the long term, and require replacement. In part, this failure may be due to immunological phenomena. The frequency of helper T lymphocytes (HTLf) measured in peripheral blood and spleen serves as a parameter for acute rejection in organ transplantation. The value of this parameter in valve transplantation was studied using the 'Rotterdam' implantation model in rats. HTLf were determined in peripheral blood and spleen at seven and 21 days after allogeneic (WAG-->DA) and syngeneic (DA-->DA) implantation of an aortic valved conduit. Valve competence was tested pre-implantation, at days 7 and 21 after implantation, and after explantation using a retrograde saline injection. Explanted valves were examined histologically. At seven days after allogeneic valve transplantation, HTLf in spleen (med...
Frontiers in Immunology, 2012
Experimental studies have established the use of mesenchymal stem cells (MSC) as a candidate immu... more Experimental studies have established the use of mesenchymal stem cells (MSC) as a candidate immunosuppressive therapy. MSC exert their immunomodulatory function through the inhibition of CD4 + and CD8 + T cell proliferation. It is unknown whether MSC impair the immunosuppressive function of regulatory T cells (Treg). In vitro and in vivo studies suggest that MSC mediate their immunomodulatory effects through the induction of Treg. In this review we will focus on the interactions between MSC and Treg, and evaluate the consequences of these cellular interplays for prospective MSC immunotherapy in organ transplantation.
BMJ open, 2015
Delayed graft function due to ischaemia-reperfusion injury is a frequent complication in deceased... more Delayed graft function due to ischaemia-reperfusion injury is a frequent complication in deceased donor renal transplantation. Experimental evidence indicates that remote ischaemic conditioning (RIC) provides systemic protection against ischaemia-reperfusion injury in various tissues. 'Remote ischaemic conditioning in renal transplantation-effect on immediate and extended kidney graft function' (the CONTEXT study) is an investigator initiated, multicentre, randomised controlled trial investigating whether RIC of the leg of the recipient improves short and long-term graft function following deceased donor kidney transplantation. The study will include 200 kidney transplant recipients of organ donation after brain death and 20 kidney transplant recipients of organ donation after circulatory death. Participants are randomised in a 1:1 design to RIC or sham-RIC (control). RIC consists of four cycles of 5 min occlusion of the thigh by a tourniquet inflated to 250 mm Hg, separated...
BMC Medicine, 2015
Whether overweight or obese end stage renal disease (ESRD) patients are suitable for renal transp... more Whether overweight or obese end stage renal disease (ESRD) patients are suitable for renal transplantation (RT) is often debated. The objective of this review and meta-analysis was to systematically investigate the outcome of low versus high BMI recipients after RT. Comprehensive searches were conducted in MEDLINE OvidSP, Web of Science, Google Scholar, Embase, and CENTRAL (the Cochrane Library 2014, issue 8). We reviewed four major guidelines that are available regarding (potential) RT recipients. The methodology was in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and written based on the PRISMA statement. The quality assessment of studies was performed by using the GRADE tool. A meta-analysis was performed using Review Manager 5.3. Random-effects models were used. After identifying 5,526 studies addressing this topic, 56 studies were included. We extracted data for 37 outcome measures (including data of more than 209,000 RT recipients), of which 26 could be meta-analysed. The following outcome measures demonstrated significant differences in favour of low BMI (&amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;30) recipients: mortality (RR = 1.52), delayed graft function (RR = 1.52), acute rejection (RR = 1.17), 1-, 2-, and 3-year graft survival (RR = 0.97, 0.95, and 0.97), 1-, 2-, and 3-year patient survival (RR = 0.99, 0.99, and 0.99), wound infection and dehiscence (RR = 3.13 and 4.85), NODAT (RR = 2.24), length of hospital stay (2.31 days), operation duration (0.77 hours), hypertension (RR = 1.35), and incisional hernia (RR = 2.72). However, patient survival expressed in hazard ratios was in significant favour of high BMI recipients. Differences in other outcome parameters were not significant. Several of the pooled outcome measurements show significant benefits for &amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;low&amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; BMI (&amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;30) recipients. Therefore, we postulate that ESRD patients with a BMI &amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;30 preferably should lose weight prior to RT. If this cannot be achieved with common measures, in morbidly obese RT candidates, bariatric surgery could be considered.
Transplant international : official journal of the European Society for Organ Transplantation, 2015
The aim of this study was to evaluate the role of ureteral length on urological complications. Da... more The aim of this study was to evaluate the role of ureteral length on urological complications. Data were retrospective collected from the INEX-trial database, a RCT to compare the intravesical to the extravesical ureteroneocystostomy. Ureteral length was measured in 198 recipients and used to divide recipients into three categories based on interquartile ranges: short (≤8.5 cm), medium (8.6-10.9 cm) and long ureters (≥11 cm). Urological complications were defined as the number of percutaneous nephrostomy placements (PCN). Fifty recipients fell into the short, 98 into the medium and 50 recipients into the long ureter category. Median follow-up was 26 (range 2-45) months. There was no significant difference in number of PCN placements between the categories. There were 9 (18%) PCN placements in the short ureter category, 21 (20%) in medium ureter category and 10 (21%) in the long ureter category, P = 0.886. Risk factor analysis for gender, arterial multiplicity and type of ureteroneoc...
PLOS ONE, 2015
Preoperative fasting and dietary restriction offer robust protection against renal ischemia/ repe... more Preoperative fasting and dietary restriction offer robust protection against renal ischemia/ reperfusion injury (I/RI) in mice. We recently showed that Mannan-binding lectin (MBL), the initiator of the lectin pathway of complement activation, plays a pivotal role in renal I/RI. Based on these findings, we investigated the effect of short-term DR (30% reduction of total food intake) or three days of water only fasting on MBL in 10-12 weeks old male C57/Bl6 mice. Both dietary regimens significantly reduce the circulating levels of MBL as well as its mRNA expression in liver, the sole production site of MBL. Reconstitution of MBL abolished the protection afforded by dietary restriction, whereas in the fasting group the protection persisted. These data show that modulation of MBL is involved in the protection against renal I/RI induced by dietary restriction, and suggest that the mechanisms of protection induced by dietary restriction and fasting may be different.
American Journal of Transplantation
The aim of this study is to review the surgical outcome of kidney retransplantation in the ipsila... more The aim of this study is to review the surgical outcome of kidney retransplantation in the ipsilateral iliac fossa in comparison to first kidney transplants. The database was screened for retransplantations between 1995 and 2013. Each study patient was matched with 3 patients with a first kidney transplantation. Just for graft and patient survival analyses, we added an extra control group including all patients receiving a second transplantation in the contralateral iliac fossa. We identified 99 patients who received a retransplantation in the ipsilateral iliac fossa. There was significantly more blood loss and longer operative time in the retransplantation group. The rate of vascular complications and graft nephrectomies within 1 year was significantly higher in the study group. The graft survival rates at 1 year and 3, 5, and 10 years were 76%, 67%, 61%, and 47% in the study group versus 94%, 88%, 77%, and 67% (p < 0.001) in the first control group versus 91%, 86%, 78%, and 57%...
Current Opinion in Organ Transplantation, 2003
ABSTRACT
Obesity, 2015
Brown adipose tissue (BAT) can generate heat by burning fatty acids, a process mediated by uncoup... more Brown adipose tissue (BAT) can generate heat by burning fatty acids, a process mediated by uncoupling protein 1 (UCP1). White adipose tissue (WAT) depots can gain BAT-like properties, and various studies have suggested that females have more active BAT or BAT-like WAT. We studied sex differences in BAT-like properties of human perirenal adipose tissue. Perirenal and subcutaneous adipose tissue was obtained from 20 male and 24 female healthy live kidney donors. Mesenchymal stem cells (MSCs), adipocyte precursor cells, were isolated from these depots to study whether intrinsic factors control BAT-like properties of the adipose tissue depots. When average outside temperature a week before harvesting was below 11°C, brown-like adipocytes expressing UCP1 were present in perirenal adipose tissue of women, but not of men. MSCs derived from perirenal adipose tissue expressed significantly more UCP1 when from female origin compared to male origin (P = 0.009). However, UCP1 protein content and oxygen consumption rate did not differ between adipocytes derived from male and female perirenal MSCs. Female perirenal adipose tissue has a higher potency to gain BAT-like properties than male perirenal adipose tissue. The degree of gaining BAT-like properties depends on sex-specific intrinsic factors and environmental triggers such as temperature.
Journal of Transplantation, 2015
Transplantation, Jan 8, 2015
With the recent transposition of Directive 2010/53/EU into the transplant regulation of EU Member... more With the recent transposition of Directive 2010/53/EU into the transplant regulation of EU Member States, the time is right to have a closer look at its implications for living organ donation practice. We first discuss the relevance of the Action Plan which forms the basis for the policy of the European Commission in the field of organ donation and transplantation. We then analyze the impact of Directive 2010/53/EU which was adopted to support the implementation of the Priority Actions set out in the Action Plan. We more specifically focus on the obligations of transplant centers engaged in living organ donation and highlight their significance for clinical practice. Finally, we point out some strengths and weaknesses of the Directive in addressing living organ donation.
Transplantation, Jan 15, 2014
Informed consent in live donor nephrectomy is a topic of great interest. Safety and transparency ... more Informed consent in live donor nephrectomy is a topic of great interest. Safety and transparency are key items increasingly getting more attention from media and healthcare inspection. Because live donors are not patients, but healthy individuals undergoing elective interventions, they justly insist on optimal conditions and guaranteed safety. Although transplant professionals agree that consent should be voluntary, free of coercion, and fully informed, there is no consensus on which information should be provided, and how the donors' comprehension should be ascertained. Comprehensive searches were conducted in Embase, Medline OvidSP, Web-of-Science, PubMed, CENTRAL (The Cochrane Library 2014, issue 1) and Google Scholar, evaluating the informed consent procedure for live kidney donation. The methodology was in accordance with the Cochrane Handbook for Interventional Systematic Reviews and written based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (P...
Frontiers in immunology, 2013
Xenotransplantation, 2004
The Journal of heart valve disease, 2002
Human valve allografts are commonly used in cardiac surgery for congenital and acquired valve dis... more Human valve allografts are commonly used in cardiac surgery for congenital and acquired valve diseases. Particularly in the pediatric population, these allografts are prone to fail in the long term, and require replacement. In part, this failure may be due to immunological phenomena. The frequency of helper T lymphocytes (HTLf) measured in peripheral blood and spleen serves as a parameter for acute rejection in organ transplantation. The value of this parameter in valve transplantation was studied using the 'Rotterdam' implantation model in rats. HTLf were determined in peripheral blood and spleen at seven and 21 days after allogeneic (WAG-->DA) and syngeneic (DA-->DA) implantation of an aortic valved conduit. Valve competence was tested pre-implantation, at days 7 and 21 after implantation, and after explantation using a retrograde saline injection. Explanted valves were examined histologically. At seven days after allogeneic valve transplantation, HTLf in spleen (med...
Frontiers in Immunology, 2012
Experimental studies have established the use of mesenchymal stem cells (MSC) as a candidate immu... more Experimental studies have established the use of mesenchymal stem cells (MSC) as a candidate immunosuppressive therapy. MSC exert their immunomodulatory function through the inhibition of CD4 + and CD8 + T cell proliferation. It is unknown whether MSC impair the immunosuppressive function of regulatory T cells (Treg). In vitro and in vivo studies suggest that MSC mediate their immunomodulatory effects through the induction of Treg. In this review we will focus on the interactions between MSC and Treg, and evaluate the consequences of these cellular interplays for prospective MSC immunotherapy in organ transplantation.