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1.
Am J Nephrol ; 55(2): 245-254, 2024.
Article in English | MEDLINE | ID: mdl-38198780

ABSTRACT

INTRODUCTION: Serum activin A has been reported to contribute to vascular calcification and kidney fibrosis in chronic kidney disease. We aimed to investigate whether higher serum activin levels were associated with poor allograft outcomes in patients with kidney transplantation (KT). METHODS: A total of 860 KT patients from KNOW-KT (Korean Cohort Study for Outcome in Patients with Kidney Transplantation) were analyzed. We measured serum activin levels pre-KT and 1 year after KT. The primary outcome was the composite of a ≥50% decline in estimated glomerular filtration rate and graft failure. Multivariable cause-specific hazard model was used to analyze association of 1-year activin levels with the primary outcome. The secondary outcome was coronary artery calcification score (CACS) at 5 years after KT. RESULTS: During the median follow-up of 6.7 years, the primary outcome occurred in 109 (12.7%) patients. The serum activin levels at 1 year were significantly lower than those at pre-KT (488.2 ± 247.3 vs. 704.0 ± 349.6). When patients were grouped based on the median activin level at 1 year, the high-activin group had a 1.91-fold higher risk (95% CI, 1.25-2.91) for the primary outcome compared to the low-activin group. A one-standard deviation increase in activin levels as a continuous variable was associated with a 1.36-fold higher risk (95% CI, 1.16-1.60) for the primary outcome. Moreover, high activin levels were significantly associated with 1.56-fold higher CACS (95% CI, 1.12-2.18). CONCLUSION: Post-transplant activin levels were independently associated with allograft functions as well as coronary artery calcification in KT patients.


Subject(s)
Kidney Transplantation , Humans , Kidney Transplantation/adverse effects , Cohort Studies , Treatment Outcome , Graft Survival , Allografts , Activins , Risk Factors
2.
Xenotransplantation ; 31(1): e12838, 2024.
Article in English | MEDLINE | ID: mdl-38112053

ABSTRACT

BACKGROUND: αGal-deficient xenografts are protected from hyperacute rejection during xenotransplantation but are still rejected more rapidly than allografts. Despite studies showing the roles of non-Gal antibodies and αß T cells in xenograft rejection, the involvement of γδ T cells in xenograft rejection has been limitedly investigated. METHODS: Six male cynomolgus monkeys were transplanted with porcine vessel xenografts from wild-type (n = 3) or GGTA1 knockout (n = 3) pigs. We measured the proportions and T cell receptor (TCR) repertoires of blood γδ T cells before and after xenotransplant. Grafted porcine vessel-infiltrating immune cells were visualized at the end of experiments. RESULTS: Blood γδ T cells expanded and infiltrated into the graft vessel adventitia following xenotransplantation of α-Gal-deficient pig blood vessels. Pre- and post-transplant analysis of γδ TCR repertoire revealed a transition in δ chain usage post-transplantation, with the expansion of several clonotypes of δ1, δ3, or δ7 chains. Furthermore, the distinctions between pre- and post-transplant δ chain usages were more prominent than those observed for γ chain usages. CONCLUSION: γδ TCR repertoire was significantly altered by xenotransplantation, suggesting the role of γδ T cells in sustained xenoreactive immune responses.


Subject(s)
Primates , T-Lymphocyte Subsets , Animals , Male , Heterografts , Receptors, Antigen, T-Cell , Swine , Transplantation, Heterologous , Macaca fascicularis
3.
Transpl Int ; 37: 12574, 2024.
Article in English | MEDLINE | ID: mdl-39170864

ABSTRACT

The optimal target blood pressure for kidney transplant (KT) patients remains unclear. We included 808 KT patients from the KNOW-KT as a discovery set, and 1,294 KT patients from the KOTRY as a validation set. The main exposures were baseline systolic blood pressure (SBP) at 1 year after KT and time-varying SBP. Patients were classified into five groups: SBP <110; 110-119; 120-129; 130-139; and ≥140 mmHg. SBP trajectories were classified into decreasing, stable, and increasing groups. Primary outcome was composite kidney outcome of ≥50% decrease in eGFR or death-censored graft loss. Compared with the 110-119 mmHg group, both the lowest (adjusted hazard ratio [aHR], 2.43) and the highest SBP (aHR, 2.25) were associated with a higher risk of composite kidney outcome. In time-varying model, also the lowest (aHR, 3.02) and the highest SBP (aHR, 3.60) were associated with a higher risk. In the trajectory model, an increasing SBP trajectory was associated with a higher risk than a stable SBP trajectory (aHR, 2.26). This associations were consistent in the validation set. In conclusion, SBP ≥140 mmHg and an increasing SBP trajectory were associated with a higher risk of allograft dysfunction and failure in KT patients.


Subject(s)
Blood Pressure , Glomerular Filtration Rate , Graft Survival , Kidney Transplantation , Humans , Female , Male , Middle Aged , Adult , Allografts , Aged , Proportional Hazards Models , Graft Rejection , Transplant Recipients , Hypertension
4.
Am J Transplant ; 23(4): 565-572, 2023 04.
Article in English | MEDLINE | ID: mdl-36739177

ABSTRACT

Diminished immune response to coronavirus disease 2019 (COVID-19) vaccines and breakthrough infection (BI) is a major concern for solid organ transplant recipients. Humoral and cellular immune responses of kidney transplant (KT) recipients after a third COVID-19 vaccination were investigated compared to matched health care workers. Anti-severe acute respiratory syndrome coronavirus 2 spike protein antibody and severe acute respiratory syndrome coronavirus 2 specific interferon-gamma releasing assay (IGRA) were assessed. A total of 38 KT recipients, including 20 BI and 18 noninfection, were evaluated. In the KT BI group, antibody titers were significantly increased (median 5 to 724, binding antibody units/mL (P = 0.002) after the third vaccination, but IGRA responses were negligible. After BI, antibody titers increased (median 11 355 binding antibody unit/mL; P < 0.001) and there was a significant increase of IGRA responses to spike proteins (Spike1-Nil, median 0.05 to 0.41 IU/mL; P = 0.009). Antibody titers and IGRA responses were significantly higher in the BI than in the noninfection group after 6 months. Immune responses were stronger in the health care worker than in the KT cohort, but the gap became narrower after BI. In conclusion, KT recipients who experienced BI after 3 COVID-19 vaccinations acquired augmented humoral and cellular immune responses.


Subject(s)
COVID-19 , Kidney Transplantation , Humans , COVID-19 Vaccines , SARS-CoV-2 , COVID-19/prevention & control , Breakthrough Infections , Kidney Transplantation/adverse effects , Immunity, Cellular , Antibodies, Viral , Transplant Recipients , Vaccination , Immunity, Humoral
5.
Xenotransplantation ; 30(5): e12814, 2023.
Article in English | MEDLINE | ID: mdl-37493436

ABSTRACT

Xenotransplantation using pigs' liver offers a potentially alternative method to overcome worldwide donor shortage, or more importantly as a bridge to allotransplantation. However, it has been challenged by profound thrombocytopenia and fatal coagulopathy in non-human primate models. Here we suggest that a left auxiliary technique can be a useful method to achieve extended survival of the xenograft. Fifteen consecutive liver xenotransplants were carried out in a pig-to-cynomolgus model. Right auxiliary technique was implemented in two cases, orthotopic in eight cases, and left auxiliary in five cases. None of the right auxiliary recipients survived after surgery due to hemorrhage during complex dissection between the primate's right lobe and inferior vena cava. Orthotopic recipients survived less than 7 days secondary to profound thrombocytopenia and coagulopathy. Two out of five left auxiliary xenotransplants survived more than 3 weeks without uncontrolled thrombocytopenia or anemia, with one of them surviving 34 days, the longest graft survival reported to date. Left auxiliary xenotransplant is a feasible approach in non-human primate experiments, and the feared risk of thrombocytopenia and coagulopathy can be minimized. This may allow for longer evaluation of the xenograft and help better understand histopathological and immunological changes that occur following liver xenotransplantation.


Subject(s)
Blood Coagulation Disorders , Liver Transplantation , Thrombocytopenia , Animals , Humans , Swine , Transplantation, Heterologous/methods , Liver Transplantation/methods , Graft Rejection , Animals, Genetically Modified , Primates , Liver/surgery , Thrombocytopenia/surgery , Macaca fascicularis
6.
BMC Anesthesiol ; 23(1): 263, 2023 08 05.
Article in English | MEDLINE | ID: mdl-37543574

ABSTRACT

BACKGROUND: International guidelines have recommended preemptive kidney transplantation (KT) as the preferred approach, advocating for transplantation before the initiation of dialysis. This approach is advantageous for graft and patient survival by avoiding dialysis-related complications. However, recipients of preemptive KT may undergo anesthesia without the opportunity to optimize volume status or correct metabolic disturbances associated with end-stage renal disease. In these regard, we aimed to investigate the anesthetic events that occur more frequently during preemptive KT compared to nonpreemptive KT. METHODS: This is a single-center retrospective study. Of the 672 patients who underwent Living donor KT (LDKT), 388 of 519 who underwent nonpreemptive KT were matched with 153 of 153 who underwent preemptive KT using propensity score based on preoperative covariates. The primary outcome was intraoperative hypotension defined as area under the threshold (AUT), with a threshold set at a mean arterial blood pressure below 70 mmHg. The secondary outcomes were intraoperative metabolic acidosis estimated by base excess and serum bicarbonate, electrolyte imbalance, the use of inotropes or vasopressors, intraoperative transfusion, immediate graft function evaluated by the nadir creatinine, and re-operation due to bleeding. RESULTS: After propensity score matching, we analyzed 388 and 153 patients in non-preemptive and preemptive groups. The multivariable analysis revealed the AUT of the preemptive group to be significantly greater than that of the nonpreemptive group (mean ± standard deviation, 29.7 ± 61.5 and 14.5 ± 37.7, respectively, P = 0.007). Metabolic acidosis was more severe in the preemptive group compared to the nonpreemptive group. The differences in the nadir creatinine value and times to nadir creatinine were statistically significant, but clinically insignificant. CONCLUSION: Intraoperative hypotension and metabolic acidosis occurred more frequently in the preemptive group during LDKT. These findings highlight the need for anesthesiologists to be prepared and vigilant in managing these events during surgery.


Subject(s)
Anesthesia , Kidney Failure, Chronic , Kidney Transplantation , Humans , Retrospective Studies , Creatinine , Propensity Score , Graft Survival , Living Donors , Kidney Failure, Chronic/surgery , Anesthesia/adverse effects
7.
Liver Transpl ; 28(11): 1747-1755, 2022 11.
Article in English | MEDLINE | ID: mdl-35687652

ABSTRACT

Bile duct surgeries are conventionally considered to promote bacterial contamination of the surgical field. However, liver transplantation recipients' bile produced by the newly implanted liver graft from healthy living donors may be sterile. We tested bacterial contamination of autologous blood salvaged before and after bile duct anastomosis (BDA) during living donor liver transplantation (LDLT). In 29 patients undergoing LDLT, bacterial culture was performed for four blood samples and one bile sample: two from autologous blood salvaged before BDA (one was nonleukoreduced and another was leukoreduced), two from autologous blood salvaged after BDA (one was nonleukoreduced and another was leukoreduced), and one from bile produced in the newly implanted liver graft. The primary outcome was bacterial contamination. The risk of bacterial contamination was not significantly different between nonleukoreduced autologous blood salvaged before BDA and nonleukoreduced autologous blood salvaged after BDA (44.8% and 31.0%; odds ratio 0.33, 95% confidence interval 0.03-1.86; p = 0.228). No bacteria were found after leukoreduction in all 58 autologous blood samples. All bile samples were negative for bacteria. None of the 29 patients, including 13 patients who received salvaged autologous blood positive for bacteria, developed postoperative bacteremia. We found that bile from the newly implanted liver graft is sterile in LDLT and BDA does not increase the risk of bacterial contamination of salvaged blood, supporting the use of blood salvage during LDLT even after BDA. Leukoreduction converted all autologous blood samples positive for bacteria to negative. The clinical benefit of leukoreduction for salvaged autologous blood on post-LDLT bacteremia needs further research.


Subject(s)
Bacteremia , Liver Transplantation , Anastomosis, Surgical , Bile Ducts/surgery , Humans , Liver Transplantation/adverse effects , Living Donors , Postoperative Complications , Retrospective Studies
8.
Ann Surg Oncol ; 29(12): 7335-7348, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35767103

ABSTRACT

BACKGROUND: Surgery is the mainstay of treatment for retroperitoneal sarcoma (RPS), but local recurrence is common. Biologic behavior and recurrence patterns differ significantly among histologic types of RPS, with implications for management. The Transatlantic Australasian RPS Working Group (TARPSWG) published a consensus approach to primary RPS, and to complement this, one for recurrent RPS in 2016. Since then, additional studies have been published, and collaborative discussion is ongoing to address the clinical challenges of local recurrence in RPS. METHODS: An extensive literature search was performed, and the previous consensus statements for recurrent RPS were updated after review by TARPSWG members. The search included the most common RPS histologic types: liposarcoma, leiomyosarcoma, solitary fibrous tumor, undifferentiated pleomorphic sarcoma, and malignant peripheral nerve sheath tumor. RESULTS: Recurrent RPS management was evaluated from diagnosis to follow-up evaluation. For appropriately selected patients, resection is safe. Nomograms currently are available to help predict outcome after resection. These and other new findings have been combined with expert recommendations to provide 36 statements, each of which is attributed a level of evidence and grade of recommendation. In this updated document, more emphasis is placed on histologic type and clarification of the intent for surgical treatment, either curative or palliative. Overall, the fundamental tenet of optimal care for patients with recurrent RPS remains individualized treatment after multidisciplinary discussion by an experienced team with expertise in RPS. CONCLUSIONS: Updated consensus recommendations are provided to help guide decision-making for treatment of locally recurrent RPS and better selection of patients who would potentially benefit from surgery.


Subject(s)
Biological Products , Liposarcoma , Retroperitoneal Neoplasms , Sarcoma , Soft Tissue Neoplasms , Adult , Humans , Neoplasm Recurrence, Local/surgery , Retroperitoneal Neoplasms/pathology , Retroperitoneal Neoplasms/surgery , Retrospective Studies , Sarcoma/pathology , Sarcoma/surgery
9.
Transpl Int ; 35: 10714, 2022.
Article in English | MEDLINE | ID: mdl-36187463

ABSTRACT

Some kidney donors have diabetes, and little of their natural course of diabetic nephropathy (DN) is known. The aim of this study was to analyze the changes in pathologic lesions in the diabetic donor kidney after KT by performing protocol biopsy two weeks and one year after KT. This retrospective study included 103 patients who underwent KT, with kidneys from donors with a history of diabetes mellitus (DM). Among them, data of 34 patients who underwent biopsy two weeks and one year after KT were reviewed. Biopsy specimens were reviewed using light microscopy and electron microscopy. Glomerular basement membrane (GBM) thickness at 2 weeks and 1 year was compared. Biopsy showed that DN occurred in 29 of the 34 patients. Only trivial histological changes were observed in 22 patients (64.7%), including 5 patients who did not show DN. At one year after transplantation, there was no change in the DN histologic class in 26 patients (76.5%), and there was no statistically significant difference in the change in GBM thickness. This pattern was observed regardless of the recipient's DM or glycemic control. With this understanding, clinicians can use kidneys from DM donors with more comfort, thereby reducing the kidney discard rate.


Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Kidney Transplantation , Diabetic Nephropathies/pathology , Diabetic Nephropathies/surgery , Humans , Kidney/pathology , Kidney Transplantation/adverse effects , Retrospective Studies , Tissue Donors
10.
Am J Transplant ; 20(4): 1056-1062, 2020 04.
Article in English | MEDLINE | ID: mdl-31733034

ABSTRACT

The development of surrogate markers for long-term outcomes of kidney transplant (KT) is a focus of attention. We examined the possibility of using a combination of the area under the curve of estimated glomerular filtration rate (eGFR) for 2 years (AUCeGFR2yrs ) and percent change in eGFR between 1 and 2 years after KT (% changeeGFR1/2yr ) as a surrogate marker. We compared the predictive power of death-censored graft failure with various combinations. The combination of >2% vs ≤2% for % changeeGFR1/2yr and >1300 vs ≤1300 mL/min/month for AUCeGFR2yr had the highest Harrell C-index (0.647; 95% confidence interval [95% CI], 0.604-0.690). The death-censored graft survival rate of the group with ≤2% changeeGFR1/2yr and ≤1300 mL/min/month AUCeGFR2yr was significantly lower than those of other groups. The AUC/% change eGFR had comparable predictive power to the previously identified marker ≥30% decline in eGFR between years 1 and 3 after KT (≤-30% changeeGFR1/3yr ) (Harrell's C-index = 0.645 [95% CI 0.628-0.662] for ≤-30% changeeGFR1/3yr ). The proposed combination might be useful as a surrogate marker in KT trials because it requires a shorter surveillance period than the established marker while having comparable predictive power.


Subject(s)
Kidney Transplantation , Glomerular Filtration Rate , Graft Survival , Treatment Outcome
11.
J Viral Hepat ; 27(7): 739-746, 2020 07.
Article in English | MEDLINE | ID: mdl-32057171

ABSTRACT

Nowadays, intensive immunosuppressive therapy including rituximab is commonly used prior to kidney transplantation (KT), raising concerns over hepatitis B virus (HBV) reactivation among hepatitis B surface antigen (HBsAg)-negative and anti-hepatitis B core (HBc)-positive KT recipients. Recent practice guidelines suggested watchful monitoring or antiviral prophylaxis for the first 6-12 months, the period of maximal immunosuppression. However, the actual risk for HBV reactivation, and whether short-term antiviral therapy in the early period is necessary, remains unclear. A total of 449 HBsAg-negative and anti-HBc-positive KT recipients were analysed for HBV reactivation. During a median follow-up of 6.7 (interquartile range: 4.2-9.4) years, HBV reactivation was observed in 9 patients (2.0%). The median time of HBV reactivation from KT was 2.8 years (range: 1.4-11.5 years), with cumulative incidence rates of 0%, 1% and 2% for 1, 3 and 5 years, respectively. There were no severe adverse outcomes, including liver transplantation or mortality related to HBV reactivation. The risk of HBV reactivation was not high, even in anti-HBs-negative patients (n = 60, 4% at 5 years), ABO mismatch (n = 92, 4% at 5 years), use of rituximab (n = 66, 3% at 5 years) or plasmapheresis (n = 17, 7% at 5 years), and acute rejection (n = 169, 3% at 5 years). In conclusion, the HBV reactivation risk was not high and the time of detection was not clustered in the early post-KT period. Our findings favour continued watchful monitoring over antiviral prophylaxis in the early period.


Subject(s)
Hepatitis B , Immunosuppressive Agents/adverse effects , Kidney Transplantation , Virus Activation , Antiviral Agents/therapeutic use , Hepatitis B/etiology , Hepatitis B Antibodies , Hepatitis B Core Antigens , Hepatitis B Surface Antigens , Hepatitis B virus/immunology , Humans , Rituximab/adverse effects , Transplant Recipients
12.
Transpl Int ; 33(1): 68-75, 2020 01.
Article in English | MEDLINE | ID: mdl-31429502

ABSTRACT

The aim of the study was to evaluate the association between postoperative hyperglycemia and CMV infection. We analyzed 741 CMV seropositive recipients, of livers from seropositive living donors, who underwent preemptive CMV treatment without CMV prophylaxis. The primary outcome was early CMV infection within 1 month after surgery. Hyperglycemia was defined when mean postoperative blood glucose concentration was >180 mg/dl based on previous research and guidelines. Survival analysis was performed using the Fine and Gray model by accounting for the competing risk of CMV infection-unrelated death. Of the 741 recipients (hyperglycemic group, n = 287; nonhyperglycemic group, n = 454), 372 (50.2%) recipients developed cytomegalovirus (CMV) infection within 1 month after surgery. CMV infection risk was significantly higher in hyperglycemic group than in nonhyperglycemic group in univariable analysis [hazard ratio (HR) 1.34, 95% confidence interval (CI), 1.08-1.66; P = 0.007] and in multivariable analysis (HR 1.25, 95% CI 1.0-1.54; P = 0.038). CMV infection risk was also significantly associated with recipient age, graft ischemia time, model for end-stage liver disease score, and preoperative neutrophil-to-lymphocyte ratio (P < 0.05). In conclusion, preventing postoperative hyperglycemia appears to be an important factor decreasing the risk of CMV infection in seropositive liver transplant recipients undergoing preemptive CMV treatment.


Subject(s)
Cytomegalovirus Infections , End Stage Liver Disease , Hyperglycemia , Liver Transplantation , Antiviral Agents/therapeutic use , Cytomegalovirus , Cytomegalovirus Infections/drug therapy , Cytomegalovirus Infections/epidemiology , Cytomegalovirus Infections/prevention & control , Humans , Hyperglycemia/complications , Liver Transplantation/adverse effects , Retrospective Studies , Severity of Illness Index , Transplant Recipients
13.
BMC Nephrol ; 21(1): 3, 2020 01 06.
Article in English | MEDLINE | ID: mdl-31902366

ABSTRACT

PURPOSE: Dual kidney transplantation (DKT) offers a way to extend the use of kidneys from expanded criteria donors (ECDs). Here, we compared the outcomes of DKT with those of single kidney transplantation from standard criteria donors (SCDs) and ECDs. METHODS: In 2014, we began performing DKT using both kidneys from deceased donors greater than 70 years of age with one of two risk factors: serum creatinine (sCr) level over 3.0 mg/dl or eGFR under 30 ml/min. By 2017, we had performed 15 DKTs. We compared the outcomes of the 15 DKT recipients with those of 124 patients who received a kidney from an SCD and 80 patients who received a kidney from an ECD. RESULTS: Compared with ECDs and SCDs, DKT donors were older, had a higher diabetes burden, and a higher sCr level (p < 0.01, < 0.01, and 0.03, respectively). DKT recipients were also older and had a higher diabetes burden than recipients of kidneys from ECDs and SCDs (p < 0.01, both). DKT recipients had a lower nadir sCr and shorter duration to nadir sCr than single ECD KT recipients (p < 0.01and 0.04, respectively). CONCLUSIONS: The survival rates of DKT grafts were compatible with those of single KT grafts. Therefore, DKT may be considered a suitable an option to expand the donor pool.


Subject(s)
Kidney Transplantation , Tissue Donors , Adult , Aged , Cadaver , Creatinine/blood , Diabetes Mellitus , Female , Glomerular Filtration Rate , Graft Survival , Humans , Kidney Transplantation/methods , Male , Middle Aged , Survival Analysis
14.
Liver Transpl ; 25(11): 1642-1650, 2019 11.
Article in English | MEDLINE | ID: mdl-31271699

ABSTRACT

Donor safety and graft results of pure laparoscopic living donor right hepatectomy (LLDRH) have previously been compared with those of open living donor right hepatectomy (OLDRH). However, the clinical outcomes of recipients at 1-year follow-up have never been accurately compared. We aimed to compare 1-year outcomes of recipients of living donor right liver transplantation (LRLT) using pure LLDRH and OLDRH. From May 2013 to May 2017, 197 consecutive recipients underwent LRLT. Donor hepatectomies were performed either by OLDRH (n = 127) or pure LLDRH (n = 70). After propensity score matching, 53 recipients were included in each group for analysis. The clinical outcomes at 1-year follow-up were compared between the 2 groups. The primary outcome was recipient death or graft failure during the 1-year follow-up period. In the propensity-matched analysis, the incidence of death or graft failure during the 1-year follow-up period was not different between the 2 groups (3.8% versus 5.7%; odds ratio [OR], 1.45; 95% confidence interval [CI], 0.24-8.95; P = 0.69). However, the composite of Clavien-Dindo 3b-5 complications was more frequent in the pure LLDRH group (OR, 2.62; 95% CI, 1.15-5.96; P = 0.02). In conclusion, although pure LLDRH affords a comparable incidence of fatal complications in recipients, operative complications may increase at the beginning of the program. The safety of the recipients should be confirmed to accept pure LLDRH as a feasible option.


Subject(s)
End Stage Liver Disease/surgery , Graft Rejection/epidemiology , Hepatectomy/adverse effects , Laparoscopy/adverse effects , Liver Transplantation/adverse effects , Postoperative Complications/epidemiology , Tissue and Organ Harvesting/adverse effects , Adult , End Stage Liver Disease/mortality , Feasibility Studies , Female , Follow-Up Studies , Graft Rejection/etiology , Graft Survival , Hepatectomy/methods , Humans , Incidence , Length of Stay , Liver Transplantation/methods , Living Donors/statistics & numerical data , Male , Middle Aged , Operative Time , Patient Safety/statistics & numerical data , Postoperative Complications/etiology , Propensity Score , Retrospective Studies , Tissue and Organ Harvesting/methods , Transplant Recipients/statistics & numerical data , Treatment Outcome , Young Adult
15.
Xenotransplantation ; 26(1): e12457, 2019 01.
Article in English | MEDLINE | ID: mdl-30183120

ABSTRACT

We designed this study to define reference values of the cynomolgus monkey coagulation system, as the normal range of values has not been established. Measurement of coagulation function was determined by testing plasma samples from 30 healthy male cynomolgus monkeys. Prothrombin time (PT), PT activity, PT international normalized ratio (INR), activated prothrombin time (aPTT), antithrombin III activity, factor II, V, VII, VIII, IX, X, XI, and XII, protein C activity, protein S activity, and d-dimer were measured using standardized techniques. Mean age and body weight were 69.5 ± 11.8 months and 5.3 ± 0.8 kg, respectively. The mean PT, PT activity, PT INR, aPTT, and antithrombin III activities were 11.72 seconds (95% CI = 10.55-12.88), 143.4% (95% CI = 102.0-184.9), 0.85 (95% CI = 0.74-0.96), 28.2 seconds (95% CI = 23.24-33.09), and 99.7% (95% CI = 79.2-120.3), respectively. The mean activities of factors II, V, VII, VIII, IX, X, XI, and XII were 110.2% (95% CI = 88.8-131.5), 134.1% (95% CI = 73.0-195.2), 318.9% (95% CI = 185.0-452.9) 160.2% (95% CI = 96.9-261.3), 38.0% (95% CI = 20.9-55.1), 85.7% (95% CI = 61.4-110.0), 155.0% (95% CI = 81.4-228.6), and 353.7% (95% CI = 246.7-460.6), respectively. The mean activities of protein C and protein S were 195.7% (95% CI = 133.4-258.0) and 122.7% (95% CI = 83.2-162.3), respectively. The mean level of d-dimer was 1.80 µg/mL (95% CI = 0.27-3.33). Factors V (P = 0.008), IX (P = 0.002), and XI (P = 0.002), and protein S activity (P = 0.025) were positively correlated with age. Our study presented the baseline values of coagulation biomarkers of cynomolgus monkeys. Despite the similarity to previous published studies, more data are required to elucidate the age effect on coagulation biomarkers.


Subject(s)
Biomarkers/blood , Blood Coagulation Factors/metabolism , Blood Coagulation/physiology , Transplantation, Heterologous , Animals , Humans , Macaca fascicularis , Male , Protein C/biosynthesis , Prothrombin Time , Transplantation, Heterologous/methods
16.
J Pharmacol Sci ; 139(2): 65-71, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30573325

ABSTRACT

Tacrolimus is one of the most commonly used immunosuppressive agents in animal models of transplantation. However, in these models, oral administration is often problematic due to the lowered compliance associated with highly invasive surgery and due to malabsorption in the intestinal tract. Therefore, we carried out a study to determine the pharmacokinetics of tacrolimus after intramuscular (IM) injection and to determine the optimal IM dosing regimens in primate models. Six male cynomolgus monkeys (Macaca fascicularis) were used in the study. Doses of 0.1 mg/kg and 5 mg were administered via IM injection and oral administration, respectively, once to determine single-dose pharmacokinetics and once daily for 5 days to determine multiple-dose pharmacokinetics. According to pharmacokinetic model estimates, the inter- and intra-individual variabilities in bioavailability following IM injection were remarkably reduced compared with those following oral administration. Monte Carlo simulations revealed that Cpeak, Ctrough and AUC would also have less variability following IM injection compared with oral administration. In this study, we found that the pharmacokinetic characteristics of tacrolimus were more constant following IM injection compared with oral administration. These results suggest that IM injection can be an alternative route of administration fin non-human primate model studies.


Subject(s)
Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/pharmacokinetics , Tacrolimus/administration & dosage , Tacrolimus/pharmacokinetics , Administration, Oral , Animals , Area Under Curve , Immunosuppressive Agents/toxicity , Injections, Intramuscular , Macaca fascicularis , Male , Models, Biological , Tacrolimus/toxicity
17.
Int J Clin Oncol ; 24(5): 583-589, 2019 May.
Article in English | MEDLINE | ID: mdl-30604162

ABSTRACT

BACKGROUND: This study was designed to identify the optimal maximum duration for delaying salvage operation when recurrence of retroperitoneal liposarcoma (LPS) is suspected. METHODS: Patients who underwent salvage operation at Samsung Medical Center for recurrent retroperitoneal LPS from January 2000 to December 2015 were reviewed. The time interval between recurrence and operation for recurrence was divided by 1, 2 or 3 months. A Cox proportional-hazards model was used to analyze factors related to disease-free survival along with recurrence-to-operation interval divided by 1, 2 or 3 months. RESULTS: The 1-, 3-, and 5-year disease-free survival rates were 43.2%, 15.6% and 13.4%, respectively. FNCLCC grade (p = 0.023) and recurrence-to-operation interval divided by 3 months (p = 0.003) were significant factors associated with recurrence. FNCLCC grade 2 (HR 1.940, CI 0.935-4.026, p = 0.238) and grade 3 (HR 4.049, CI 1.767-9.281, p = 0.007) showed increased risk compared to grade 1. Patients who underwent salvage operation more than 3 months after recurrence showed significantly increased risk of recurrence compared to patients within 3 months (HR 2.724, CI 1.391-5.337, p = 0.003). CONCLUSIONS: Based on our analysis of recurrence-free survival, salvage operation can be delayed for less than 3 months when recurrence is suspected. A short-term follow-up imaging study should be performed within this period.


Subject(s)
Liposarcoma/mortality , Liposarcoma/surgery , Retroperitoneal Neoplasms/mortality , Retroperitoneal Neoplasms/surgery , Salvage Therapy/methods , Adult , Aged , Disease-Free Survival , Female , Humans , Liposarcoma/pathology , Male , Middle Aged , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/surgery , Postoperative Care , Prognosis , Proportional Hazards Models , Retroperitoneal Neoplasms/pathology , Survival Rate , Time Factors , Tomography, X-Ray Computed
18.
Urol Int ; 103(4): 482-487, 2019.
Article in English | MEDLINE | ID: mdl-31645045

ABSTRACT

PURPOSE: To evaluate the long-term cure and complication rates of the canal transobturator tape (TOT) procedure for stress urinary incontinence (SUI) in females and assess how to reduce mesh erosion in TOT surgery. MATERIALS AND METHODS: The canal TOT procedure was developed in 2009 and was effective in mitigating the complications of the original TOT procedure in the short-term follow-up. This study was designed for a long-term follow-up. Between October 2006 and December 2010, 232 consecutive women with stress and mixed urinary incontinence underwent the canal TOT procedure. All patients were followed up by urological examination and self-assessment questionnaires. We performed urodynamic studies in patients with pure SUI symptoms and pelvic examination for all patients 5 years post-surgery. RESULTS: A minimum 5 years follow-up data were available for 144 patients. Complications were evaluated according to the Clavien-Dindo classification. Vaginal mesh erosion was reported in 2 patients (1.4%), and the mesh was surgically removed. No bladder or urethral mesh erosion were observed. The subjective and objective cure rates at 5 years were 77.8 and 94.5% respectively. CONCLUSIONS: Canal TOT procedure is an effective minimally invasive procedure with satisfactory results for female SUI in the long term. Compared to the rate of mesh erosion after the original TOT procedure, this technique might be useful in preventing mesh erosion because the mesh is always anatomically well positioned.


Subject(s)
Postoperative Complications/epidemiology , Suburethral Slings , Surgical Mesh , Urinary Incontinence, Stress/surgery , Adult , Aged , Aged, 80 and over , Equipment Failure/statistics & numerical data , Female , Humans , Middle Aged , Postoperative Complications/etiology , Prospective Studies , Surgical Mesh/adverse effects , Time Factors , Treatment Outcome , Urologic Surgical Procedures/instrumentation
19.
Bioconjug Chem ; 29(9): 2945-2953, 2018 09 19.
Article in English | MEDLINE | ID: mdl-29985588

ABSTRACT

The microenvironment of pancreatic islets gets disrupted during enzyme digestion and causes islets to remain in a vulnerable state, leading to poor outcome in the initial days of transplantation. To avoid immune invasion while allowing the reconstruction of the microenvironment of the transplanted site, we propose immunoisolation polymers, which can nanoencapsulate islets quickly without cytotoxicity. Here, nonhuman primate (NHP) islets were nanoencapsulated with hyperbranched polyethylene glycol (hb-PEG) and heparin by layer-by-layer technology and transplanted into the kidney subcapsular space of diabetic C57BL/6 mice. An immunosuppressive drug protocol was applied to increase the survival time until the animals were sacrificed. The recipients of NHP islets exhibited high nonfasting blood glucose level (BGL) for 2-3 weeks, which was normalized afterward. Immunohistochemical (IHC) analysis revealed an immature vascular basement membrane and cell surface integrins directly associated with poor initial insulin production. The transplanted grafts regained their own microenvironment within a month without any outside stimuli. No lymphocyte infiltration was observed in the grafts at any time. Humoral and cell-mediated immune responses were prominently diminished by the hb-PEG/Heparin nanoencapsulated islets. Immunoisolation accompanied by an immunosuppressive drug protocol protects islets by helping them avoid immunogenesis while at the same time allowing them to reconstruct their microenvironment.


Subject(s)
Blood Glucose/metabolism , Cellular Microenvironment , Heparin/chemistry , Islets of Langerhans Transplantation/methods , Nanotechnology , Polyethylene Glycols/chemistry , Animals , Antibody Formation , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/immunology , Diabetes Mellitus, Experimental/therapy , Immunity, Cellular , Macaca fascicularis , Male , Mice , Mice, Inbred C57BL
20.
Xenotransplantation ; 25(1)2018 01.
Article in English | MEDLINE | ID: mdl-29135052

ABSTRACT

BACKGROUND: Porcine islet xenotransplantation is considered an attractive alternative treatment for type 1 diabetes mellitus. However, it is largely limited because of initial rejection due to Instant Blood-Mediated Inflammatory Reaction (IBMIR), oxidative stress, and inflammatory responses. Recently, soluble tumor necrosis factor-ɑ receptor type I (sTNF-αR) and heme oxygenase (HO)-1 genes (HO-1/sTNF-αR) have been shown to improve the viability and functionality of porcine islets after transplantation. METHODS: In this study, genetically modified mesenchymal stem cells (MSCs) expressing the HO-1/sTNF-αR genes (HO-1/sTNF-αR-MSC) were developed using an adenoviral system, and porcine islet viability and function were confirmed by in vitro tests such as GSIS, AO/PI, and the ADP/ATP ratio after coculturing with HO-1/sTNF-αR-MSCs. Subsequently, isolated porcine islets were transplanted underneath the kidney capsule of diabetic humanized mice without MSCs, with MSCs or with HO-1/sTNF-αR-MSCs. RESULTS: According to the results, the HO-1/sTNF-αR-MSC-treated group exhibited improved survival of porcine islets and could reverse hyperglycemia more than porcine islets not treated with MSCs or islets cotransplanted with MSCs. Moreover, the HO-1/sTNF-αR-MSC group maintained its morphological characteristics and the insulin secretion pattern of transplanted porcine islets similar to endogenous islets in immunocompetent humanized mice. CONCLUSIONS: Our results suggest that HO-1/sTNF-αR-MSCs are efficient tools for porcine islet xenotransplantation, and this study may provide basic information for pre-clinical animal models and future clinical trials of porcine islet xenotransplantation.


Subject(s)
Graft Survival , Heme Oxygenase-1/genetics , Heterografts/immunology , Membrane Proteins/genetics , Mesenchymal Stem Cells/cytology , Receptors, Tumor Necrosis Factor, Type I/metabolism , Animals , Coculture Techniques , Diabetes Mellitus, Experimental/immunology , Diabetes Mellitus, Experimental/therapy , Graft Survival/immunology , Humans , Immunoglobulin Fc Fragments/immunology , Islets of Langerhans/immunology , Islets of Langerhans Transplantation/methods , Mesenchymal Stem Cell Transplantation/methods , Mice, Transgenic , Transplantation, Heterologous/methods
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