Enhancing the mediated electrochemical reduction process combined with developed liquid-gas electrochemical flow sensors for sustainable N2O removal at room temperature.

New electrocatalysts with high reduction efficiency are needed to upgrade the mediated electrochemical reduction for real applications. In addition, automation is required to quantify active electrocatalysts in alkaline media and air pollution. In this study, N2O was removed sustainably by electrogenerated low valent nickel(I) phthalocyanine tetrasulfonate [Ni(I)TSPc] in 1 M KOH using an electroscrubbing system. Ni(I)TSPc electro generation and N2O removal were automated by two (liquid/gas) electrochemical flow sensors, respectively. The Ni(I)TSPc was generated electrochemically up to 95% in 1 M KOH, and high removal efficiency (100%) was observed for 5 ppm N2O and 90% for 10 ppm N2O. A limiting potential change in the in-situ LSV of the chemically synthesized Ni(I)TSPc was taken and derived from the calibration plot and validated by an ex-situ potentiometric titration using an oxygen reduction potential electrode. Using the obtained calibration plot, electrogenerated Ni(I)TSPc allowed a direct determination in a liquid flow cell. The gas flow sensor developed using a KOH/Ni(II)CN4 (TCN (II))-fabricated silver solid amalgam electrode showed an excellent response to N2O concentrations up to 32 ppm. A calibration plot with known concentration was derived and validated by gas chromatography. The response time and sensitivity obtained were approximately 500s and -0.012 mA ppm-1 cm-2, respectively. The sensor stability test confirmed its good stability. Finally, the developed in-situ electrochemical flow sensors were applied to the sustainable automation of N2O pollutant removal.

Cerium-polysulfide redox flow battery with possible high energy density enabled by MFI-Zeolite membrane working with acid-base electrolytes.

A pH change can enable high-energy-density RFB (redox flow battery) in an aqueous medium. Nevertheless, a membrane to prevent the ion crossover is needed. This study adopted cerium and polysulfide in an acid-base combined electrolyte with an MFI-Zeolite membrane as a separator. The increased potential with pH change is described by the OCP (open circuit potential) difference, which varies by 0.8 V for the combination of acid-acid and acid-base electrolyte. A decrease of 350 mV at the redox peak potential of Ce3+/Ce4+ and a 10 mV negative potential shift for S42-/2S22- highlights the pH effect between the combination of acid-acid and acid-base electrolyte indicates the influence of pH leading in half-cell of anodic than the opposite cathodic side. The UV-visible spectral analysis for Ce3+ and S42- ions displacement shows that cerium and sulfur ions do not migrate to each other half-cell through an MFI-Zeolite membrane. As a result, the current efficiency of 94%, voltage, and energy efficiency of 40%-43% were attained at a current density of 10 mA cm-2. Moreover, the acid-base composition of the Ce/S system showed an energy density of 378.3 Wh l -1.

Enhanced sustainable electro-generation of a Ni (I) homogeneous electro-catalyst at a silver solid amalgam electrode for the continuous degradation of N2O, NO, DCM, and CB pollutants.

This paper reports the sustainable and enhanced generation of a Ni(I) active electro-catalyst using AgSAE as a cathode material for the sustainable degradation of N2O, NO, dichloromethane (DCM), and chlorobenzene (CB) by electroscrubbing in a series operation. The AgSAE electrode showed 1.66 times higher Ni(I) formation than the Ag metal electrode. The AgSAE achieved 20% ± 2% Ni(I) generation in a highly concentrated alkaline medium, whereas Ag metal only achieved 12% ± 2% Ni(I) generation at the same current density. Electrochemical impedance spectroscopy and voltammetric studies determined that the kinetics of the charge-transfer reaction was also preferential at the AgSAE, with the cathodic peak at -1.26 V vs. Ag/AgCl confirming Ni(I) formation. Initially, the change in the oxygen reduction potential and reduction efficiency of Ni(I) confirmed the removal of N2O, NO, DCM and CB. In addition, the gas Fourier transform infrared (FTIR) spectrum revealed 99.8% removal efficiency of toxic pollutants. Therefore, the regeneration of Ni(I) confirmed the sustainable removal of toxic pollutants. Furthermore, the FTIR spectra revealed the formation of NH3 during the reduction of N2O and NO. On the other hand, DCM and CB were reduced to benzene derivatives in the solution phase. In addition, a plausible reduction mechanism was derived. As a result, the AgSAE cathode exhibited two-fold higher removal efficiency of N2O, NO, DCM, and CB than the previously reported electrodes.

Sustainable removal of N2O by mediated electrocatalytic reduction at ambient temperature electro-scrubbing using electrogenerated Ni(I) electron mediator.

Direct catalysis is generally proposed for nitrous oxide (N2O) abatement but catalysis is expensive, requires high temperatures, and suffers from media fouling, which limits its lifetime. In the present study, an ambient temperature electroscrubbing method was developed, coupling wet-scrubbing with an electrogenerated Ni(I) ([Ni(I)(CN)4]3-) mediator, to enable N2O reduction in a single process stage. The initial studies of 10 ppm N2O absorption into 9 M KOH and an electrolyzed 9 M KOH solution showed no removal. However, 95% N2O removal was identified through the addition of Ni(I) to an electrolyzed 9 M KOH. A change in the oxidation/reduction potential from -850 mV to -650 mV occurred following a decrease in Ni(I) concentration from 4.6 mM to 4.0 mM, which confirmed that N2O removal was mediated by an electrocatalytic reduction (MER) pathway. Online analysis identified the reaction product to be ammonia (NH3). Increasing the feed N2O concentration increased NH3 formation, which suggests that a decrease in electrolyzed solution reactivity induced by the increased N2O load constrained the side reaction with the carrier gas. Importantly, this study outlines a new regenerable method for N2O removal to commodity product NH3 at ambient temperature that fosters process intensification, overcomes the limitations generally observed with catalysis, and permits product transformation to NH3.

Kidney Transplantation Using Expanded-Criteria Deceased Donors: A Comparison With Ideal Deceased Donors and Non-Expanded-Criteria Deceased Donors.

PURPOSE: The use of expanded-criteria deceased-donor (ECD) kidneys must be evaluated within the objective perspective of critical organ shortage and graft function and survival. In this study, we aimed to compare the clinical outcomes of ECD reliance with concurrent use of ideal-criteria deceased donors (IDDs) and non-ECDs in adult renal transplantation. METHODS: Between February 2000 and December 2015, we analyzed 405 deceased-donor renal transplants, specifically 129 grafts (31.9%) from ECDs, 233 grafts (57.5%) from non-ECDs, and 43 grafts (10.6%) from IDDs. ECDs were classified according to the United Network for Organ Sharing guidelines, while an IDD was defined as a younger person (10-39 years of age) with no medical risk factors who died from a traumatic head injury. Donor and recipient risk factors were separately analyzed and correlated with recipient graft function, and survival was evaluated. RESULTS: ECDs were older (56.8 ± 6.3 years); showed increased incidence of hypertension, diabetes, and cerebrovascular brain death; and had a higher pre-retrieval serum creatinine level than the other groups. ECD kidney recipients were also older (50.6 ± 9.8 years), had a shorter waiting time (P = .031), and demonstrated a low frequency of re-transplantation (P = .028). Long-term renal function followed longitudinally was lower in ECD kidney recipients until five years after transplantation, while the glomerular filtration rate (GFR) level at 7 and 10 years did not differ significantly among the groups (P = .074 and .262, respectively). There were no significant differences in terms of graft survival (P = .394) or patient survival (P = .737) among the groups. CONCLUSIONS: Although the long-term renal function followed longitudinally was lower in ECD kidney recipients, the use of renal grafts from ECDs is an acceptable method to resolve the disparity of critical organ shortage. However, the classification of the high-risk group should be updated with consideration given to differences in regional characteristics.

Electrochemically generated bimetallic reductive mediator Cu1+[Ni2+(CN)4]1- for the degradation of CF4 to ethanol by electro-scrubbing.

Remediation of electronic gas CF4 using commercially available technologies results in another kind of greenhouse gas and corrosive side products. This investigation aimed to develop CF4 removal at room temperature with formation of useful product by attempting an electrogenerated Cu1+[Ni2+(CN)4]1- mediator. The initial electrolysis of the bimetallic complex at the anodized Ti cathode demonstrated Cu1+[Ni2+(CN)4]1- formation, which was confirmed by additional electron spin resonance results. The degradation of CF4 followed mediated electrochemical reduction by electrogenerated Cu1+[Ni2+(CN)4]1-. The removal efficiency of CF4 of 95% was achieved by this electroscrubbing process at room temperature. The spectral results of online and offline Fourier transform infrared analyzer, either in gas or in solution phase, demonstrated that the product formed during the removal of CF4 by electrogenerated Cu1+[Ni2+(CN)4]1- by electroscrubbing was ethanol (CH3CH2OH), with a small amount of trifluoroethane (CF3CH3) intermediate.

Progression of Osteoporosis After Kidney Transplantation in Patients With End-Stage Renal Disease.

BACKGROUND: This study investigated the prevalence of osteoporosis and the risk factors for its progression in kidney transplant recipients (KTRs). METHODS: Dual energy X-ray absorptiometry was used to prospectively measure changes in bone mineral density (BMD) before kidney transplantation (KT) and 1 year after transplantation in 207 individuals. We also analyzed the risk factors of osteoporosis progression during this period. RESULTS: Prior to KT, the mean BMD score (T-score of the femur neck area) was -2.1 ± 1.2, and the prevalence of osteoporosis was 41.5% (86/207). At 1 year post-transplantation, the mean BMD score significantly decreased to -2.3 ± 1.1 (P < .001), and the prevalence of osteoporosis increased to 47.3% (98/207; P = .277). The BMD score worsened over the study period in 69.1% (143/207) of patients, improved in 24.1% (50/207), and showed no change in 6.8% (14/207). Minimal intact parathyroid hormone (iPTH) improvement after KT was found to be an independent risk factor of osteoporosis progression. CONCLUSIONS: This study demonstrates progressive loss of BMD after KT and sustained secondary hyperparathyroidism might influence the progression of osteoporosis.

Effect of Donor-Recipient Age Match in Expanded Criteria Deceased Donor Kidney Transplantation.

PURPOSE: Our objective was to investigate the effects of age on patient and graft survival in expanded criteria donor (ECD) renal transplantation. METHODS: Between February 2000 and December 2015, we analyzed 405 deceased donor renal transplants, including 128 grafts (31.9%) from ECDs. Based on recipient age and ECD criteria classification, the recipients were divided into four groups: Group I, non-ECD to recipient age <50 years; Group II, non-ECD to recipient age ≥50 years; Group III, ECD to recipient age <50 years; and Group IV, ECD to recipient age ≥50 years. RESULTS: Among the four groups, there were significant differences in baseline characteristics (age, body mass index [BMI], cause of end-stage renal disease [ESRD], number of kidney transplantations, and use of induction agent). The mean modification of diet in renal disease (MDRD) glomerular filtration rate (GFR) level at 1 month, 6 months, 1 year, 3 years, and 5 years after transplantation was significantly lower in patients with ECDs but MDRD GFR level at 7, 9, and 10 years did not differ significantly (P = .183, .041, and .388, respectively). There were no significant differences in graft survival (P = .400) and patient survival (P = .147). CONCLUSION: Our result shows that, regardless of recipient age, kidney transplants donated by deceased ECDs have similar graft and patient survival.

Benefits of active middle ear implants over hearing aids in patients with sloping high tone hearing loss: comparison with hearing aids.

In this retrospective chart review we compared the subjective and objective benefits of active middle ear implants (AMEIs) with conventional hearing aids (HAs) in patients with sloping high tone hearing loss. Thirty-four patients with sensorineural hearing loss were treated with AMEIs. Of these, six had sloping high tone hearing loss and had worn an HA for more than 6 months. Objective assessments, a pure-tone audiogram, as well as a word recognition test, and the Korean version of the Hearing in Noise Test (K-HINT), and a subjective assessment, the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire, were performed. Tests were conducted under three circumstances: 1) the unaided state before surgery; 2) the HA-aided state before surgery; and 3) the AMEI-aided state 3 months after surgery. The average high-frequency hearing gain (≥ 2 kHz) was significantly better with AMEIs than with HAs. Although the result had no statistical significance, AMEIs showed a superior word recognition score (WRS) compared to HAs. However, the most comfortable hearing level at which the WRS was tested was significantly decreased with an AMEI compared to an HA. In the K-HINT, patients with an AMEI showed greater recognition than those fitted with an HA under both quiet and noisy conditions. The APAHB scores revealed that patients were more satisfied with an AMEI rather than an HA on all subscales. The use of vibroplasty in patients with sloping high tone loss resulted in positive hearing outcomes when compared to conventional HAs. Based on the data from this study, AMEIs provided better objective and subjective results and could, therefore, be a better alternative for the treatment of sloping hearing loss.

Innovative reductive remediation of carbon tetrafluoride at room temperature by using electrogenerated Co1.

Among the non-CO2 greenhouse gases, carbon tetrafluoride (CF4) is the most recalcitrant and should be eliminated from the atmosphere. In the present study, a non-combustion electroscrubbing method was used in an attempt to degrade CF4 with an electrogenerated Co1+ mediator in a highly alkaline medium. The initial absorption experiments revealed 165mgL-1 CF4 gas dissolved in 10M NaOH. Different mediator precursors, [Co(II)(CN)5]3-, [Ni(II)(CN)4]2-, [Cu(II)(OH)4]2-, and [Co(II)(OH)4]2-, were used and the electroscrubbing results showed that the electrogenerated Co1+ or [Co(II)(OH)4]2- precursor effectively degraded up to 99.25% of the CF4 gas. The variations in [Co(II)(OH)4]2- reduction efficiency and cyclic voltammetry revealed CF4 degradation followed by electrogenerated Co1+ mediated reduction. The increased zeta potential (+6mV) of the electrogenerated Co1+ showed that the degradation reaction occurs preferably at the solution interface. Electroscrubbing for CF4 removal and the resulting products were controlled by the carrier gas. Air and H2 carrier gases lead to the formation of CHF3 and COF2. N2 as the carrier gas caused 99.25% degradation with ethanol as a product. An 80% CF4 degradation efficiency with CHF3 as the product was observed when a mixture of N2 and air was used as the carrier gas.

Ureteral Complications in Kidney Transplantation: Analysis and Management of 853 Consecutive Laparoscopic Living-Donor Nephrectomies in a Single Center.

BACKGROUND: We report the incidence and nature of ureteral and surgical complications in our series of 853 consecutive living-donor renal transplants after laparoscopic living-donor nephrectomy. The aim of this study was to analyze the therapeutic approaches to ureteral complications in kidney transplantations and their relationship with recipient outcome. METHODS: The medical records of patients who underwent kidney transplantation from 2000 to 2014 were reviewed retrospectively. After the donor nephrectomies were performed with the use of laparoscopic, hand-assisted laparoscopic, and vesico-ureteral anastomosis, the recipient's ureteral complications were classified according to the mechanism and site of urinary tract involvement: anastomosis stricture, anastomosis leakage, vesico-ureteral reflux, and urolithiasis. RESULTS: Among the 853 cases of kidney transplantation, ureteral complications occurred in 66 patients (7.73%). The most common complication was urinary tract infection caused by vesico-ureteral reflux (n = 24, 2.81%), which was managed with by means of sub-ureteral polydimethylsiloxane injection. The second most common complication was the anastomosis site stricture (n = 23, 2.69%), which was treated by means of ureteral re-implantation or percutaneous nephrostomy. Anastomosis site leakage occurred in 11 patients (1.28%) and was managed by percutaneous nephrostomy with double-J stenting and drainage or ureteral re-implantation. Urolithiasis occurred in 8 patients (0.93%). CONCLUSIONS: There was an 8% rate of recipient ureteral complications at our institution. Of the 66 patients, 46 (5.4%) required surgical repair. The remaining 20 patients with ureteral complications were treated with conservative care or minimally invasive procedures. The keys to successful management of these problems are early diagnosis and prompt reconstruction whenever possible. Most ureteral complications are easily managed with a successful outcome with early intervention.

Impact of Pretransplant Panel-Reactive Antibody Level on Renal Graft Survival in Patients With a Negative Crossmatch and No Donor-Specific Antibody.

BACKGROUND: Patients with high panel-reactive antibody (PRA) levels before transplantation tend to remain on the waiting list longer when considering cadaveric donor transplantation and have worse outcomes than those with lower PRA levels. This study investigated the impact of the pretransplantation PRA level on rejection and graft survival after kidney transplantation in patients with a negative crossmatch (CXM(-)) and no donor-specific antibody (DSA(-)). METHODS: We retrospectively analyzed 513 recipients of kidney allograft treated from January 2009 to April 2013. Those who tested positive on crossmatching, had donor-specific antibodies, were ABO incompatible, or had no PRA level data were excluded (n = 130). The remaining patients were stratified into 3 groups according to their PRA levels: group I, PRA = 0 (314 [80.1%]); group II, PRA ≤50% (27 [7.2%]); and group III, PRA >50% (27 [7.2%]). Graft failure was defined as a return to dialysis, transplant nephrectomy, or death with a functioning kidney. RESULTS: The mean patient follow-up was 30.4 ± 4.6 months. The rejection rate was 20.1% (group I, 18.5% [n = 58] vs group II, 23.8% [n = 10] vs group III, 33.3% [n = 9] [P = .053]). The graft failure rate was 21.7% (group I, 6.4% [n = 20] vs group II. 7.1% [n = 3] vs group III, 7.4% [n = 7] [P = .792]), and the 3-year graft survival rates were 96.3, 92.4, and 92.5%, respectively (P = .851). CONCLUSIONS: The pretransplant PRA level was not significantly associated with graft survival in patients with CXM(-) and DSA(-). However, the rejection rate tended toward significance as the PRA level increased (P = .053).

Clinical Outcome of Simultaneous Native Nephrectomy and Kidney Transplantation in Patients With Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: End-stage renal disease patients with autosomal dominant polycystic kidney disease may require native nephrectomy for various indications. However, the appropriate timing for nephrectomy in kidney transplantation and its effect on allograft survival have not been fully investigated. METHODS: We retrospectively analyzed 41 kidney transplant recipients with autosomal dominant polycystic kidney disease in whom transplantation was done simultaneously, after, or without native nephrectomy at Seoul St. Mary's hospital between January 1987 and February 2014. We divided patients into 2 groups based on when native nephrectomy was performed: simultaneously (group A, n = 13) and after or without nephrectomy (group B, n = 28), and compared perioperative outcomes, posttransplantation complications, and allograft survival rates. RESULTS: The mean operative time was significantly longer in group A than in group B (6.48 ± 1.84 vs 5.27 ± 0.84 hours; P = .048). The mean numbers of units required for intraoperative blood transfusions were also significantly higher in group A than in group B (3.66 ± 3.43 vs 0.75 ± 0.26 units; P = .018). However, there were no differences between groups in the incidence of acute rejection and other complications such as postoperative bleeding and infectious complications (P > .05, for all). The allograft survival rate also did not differ between groups (P > .05). CONCLUSIONS: Our study showed that patients undergoing simultaneous nephrectomy and kidney transplantations had clinical outcomes, in terms of complications and allograft survival, that were comparable to those in patients undergoing kidney transplantations with or without previous nephrectomy.

Characteristics of Femoral Motor Neuropathies Induced After Kidney Transplantation: A Case Series.

BACKGROUND: Femoral motor neuropathy (FMN) induced after kidney transplantation (KT) can injure the patient and graft, and it sometimes can leave sequelae on gait. Nevertheless, the cause of FMN has not been determined. We assessed 5 cases of FMN in an attempt to determine the traits induced after KT. METHODS: Patient data about general characteristics, immunologic characteristics, operative findings, post-operative status, and FMN characteristics were assessed. A Bookwalter self-retaining retractor was used and quadruple immunosuppression was implemented in all cases. RESULTS: Five patients had FMN. Four of the 5 patients were women. The mean body mass index (BMI) was 20.38 ± 1.99 kg/m(2) prior to KT and 19.08 ± 1.98 kg/m(2) after KT. The mean graft-recipient weight ratio was 3.46 ± 0.99 g/kg. There was no case of psoas muscle abscess or hematoma. Motor function recovery was obtained 3 to 313 days after rehabilitation. Immediate graft function was favorable in all patients with no rejection or significant complications. CONCLUSIONS: FMN after KT may occur in patients with a lower BMI and higher graft-recipient weight ratio. This study was based on only 5 patients, and therefore further studies with a larger population size are necessary.

Ten-Year Experience With Bowel Transplantation at Seoul St. Mary's Hospital.

A retrospective review of intestinal transplantation (ITx) at Seoul St. Mary's Hospital was made by collecting clinical data over the past 10 years. Fifteen consecutive cases from 2004 were analyzed. Five children and 10 adults (6 months to 69 years of age) were included. Primary diseases in adults included 4 mesenteric vessel thromboses, 2 strangulations, and 1 each of visceral myopathy, malignant gastrointestinal stromal tumor (GIST), mesenteric lymphangiectasis, and injury. Pediatric cases involved 2 Hirschsprung disease, 2 visceral myopathy, and 1 necrotizing enterocolitis. Three of 7 stomas were closed using a serial transverse enteroplasty procedure before transplantation. The ITx were performed using 3 living-donor Itx, 12 deceased-donor ITx, 14 isolated Itx, and 1 modified multivisceral transplantation. Daclizumab, basiliximab, alemtusumab, or basiliximab with rabbit antithymocyte globulin (rATG) was used for the induction; tacrolimus monotherapy was used as the basic maintenance immunosuppressant; and m-TOR inhibitor was used for renal dysfunction patients. Seven cases of acute cellular rejection were treated with rATG. Three cases of antibody-mediated rejection were treated with rituximab alone or with rituximab and bortezomib combination. There were 4 cases of early mortality within 6 months after Itx. Causes of death were declamping shock, cardiac tamponade with acute cellular rejection, dysmotility, and sepsis. Surgical complications consisted of 1 feeding jejunostomy displacement, and a minor leakage at a colo-colostomy site. One-year survival of the patient and graft was 73.33% (Kaplan-Meier survival curve). Although the total number of ITx is small, its social impact has been remarkable in changing the related laws and reimbursement policy in Korea.

Gaseous trichloroethylene removal using an electrochemically generated homogeneous low-valent ligand-free Co(I) electrocatalyst by electro-scrubbing.

The interest in heterogeneous Co(OH)2 electrocatalysts for energy applications has increased steadily. This study focused on a ligand-free homogeneous electrocatalyst for the degradation of gaseous trichloroethylene (TCE) in NaOH in a divided electrolytic cell. The initial electrolysis results revealed a change in the oxidation reduction potential (ORP) of [Co(II)(OH)4](2-) (Co(II)) from -267 mV to -800 mV on anodized Ti during electrolytic reduction identifies low-valent homogeneous [Co(I)(OH)4](3-)(Co(I)) formation in 10 M NaOH. Cyclic voltammetry analysis of Co(II) at different anodized electrodes, Ag, carbon and Ti, in a 10 M NaOH solution, showed no stripping like peak in the reverse scan only the Ti electrode, supporting the formation of low-valent Co(I). UV-vis spectral analysis of the electrolyzed solution showed an enhanced peak corresponding to metal-to-ligand transition, demonstrates Co(I) formation. Co(II) reduction reached a maximum yield of 18% at 30 mA cm(-2) on an anodized Ti cathode. For gaseous TCE removal, continuous mode electro-scrubbing was adopted and degradation was monitored using an online FTIR gas analyzer that showed 99.75% degradation of TCE in the presence of homogeneous Co(I). Three consecutive regenerations of Co(I) and degradation steps of TCE confirmed the possibility of industrial applications in a sustainable manner.

The electrochemical oxidation of toluene catalysed by Co(II) in N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide.

The electrochemical oxidation of toluene in N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([bmpyr](+)[Ntf2](-)) was investigated by using cyclic voltammetry and galvanostatic electrolysis in the presence of Co(II) at a Pt disc working electrode. Cyclic voltammetry (CV) investigations revealed that Co(II)-Co(III) oxidation is a diffusion controlled electron transfer process. The diffusion coefficient values of Co(II) were found to increase from 0.38 × 10(-7) to 1.9 × 10(-7) cm(2) s(-1) as the temperature was increased from 25 °C to 80 °C. The CV peak current for toluene electro-oxidation increased by nearly 7 fold in the presence of Co(II) demonstrating a good catalytic effect. Co(II) catalysed galvanostatic electrolysis of toluene at room temperature has shown that benzaldehyde was formed along with a small quantity of 3-methyl-1-hexanol.

Long-term outcomes of kidney transplantation from expanded criteria deceased donors at a single center: comparison with standard criteria deceased donors.

Our objective was to compare the clinical outcomes of adult kidney transplants from expanded criteria deceased donors (ECD) with those from concurrent standard criteria deceased donors (SCD). Between January 2000 and December 2011, we transplanted 195 deceased donor renal transplants into adult recipients, including 31 grafts (15.9%) from ECDs and 164 grafts (84.1%) from SCDs. ECDs were classified using the United Network for Organ Sharing (UNOS) definitions. Donor and recipient risk factors were analyzed separately and their correlation with recipient graft function and survival was evaluated (minimum 6-month follow-up). ECDs were older (56.8 ± 6.3 years), showed an increased incidence of hypertension, diabetes, and cerebrovascular brain death, and had a higher preretrieval serum creatinine level than SCDs. ECD kidney recipients had a shorter waiting time (P = .019) but other baseline characteristics (age, gender, body mass index [BMI], cause of end-stage renal disease, type of renal replacement therapy, incidence of diabetes and hypertension, number of HLA antigen mismatches, positivity for panel-reactive antigen, and cold ischemic time) were not significantly different from those of SCD kidney recipients. Mean glomerular filtration rate (GFR) at 1 month, 6 months, 1 year, and 3 years after transplantation was significantly lower in recipients of ECD transplants than recipients of SCD transplants, but the GFR level at 5 and 10 years was not significantly different between ECD and SCD recipient groups (P = .134 and .702, respectively). Incidence of acute rejection episodes and surgical complications did not differ significantly between the 2 recipient groups, but the incidence of delayed graft function (DGF) and infectious complications was higher in ECD kidney recipients than SCD kidney recipients (P = .007 and P = .008, respectively). Actual patient and graft survival rates were similar between the 2 recipient groups with a mean follow-up of 43 months. There were no significant differences in graft survival (P = .111) or patient survival (P = .562) between the 2 groups. Although intermediate-term renal function followed longitudinally was better in SCD kidney recipients, graft and patient survival of ECD kidney recipients were comparable with those of SCD kidney recipients. In conclusion, use of renal grafts from ECDs is a feasible approach to address the critical organ shortage.

The natural history of arteriovenous access and risk factors associated with access thrombosis after successful kidney transplantation.

INTRODUCTION: The purpose of this study was to determine the natural history of arteriovenous (AV) access after successful kidney transplantation (KT) and to identify the risk factors of spontaneous access closure in kidney transplant recipients. METHODS: We performed a retrospective review of 115 patients who underwent KT with functioning access from June 2010 to July 2012. AV access patency was checked and recorded daily during the hospital stay and at every visit to the outpatient clinic. Patients were divided into 2 groups according to the patency of access, and risk factors of access thrombosis were assessed. Access patency was followed up until patency was lost or the study was closed. RESULTS: At the end of follow-up, 18 (15.7%) AV accesses had spontaneously closed. Mean time to closure was 119 ± 163 days, and 12 of 18 were closed within 90 days after KT. AV access spontaneously closed in 8.5% of male patients, compared with 27.3% of female patients (P = .007), 12.2% of cases with native access compared with 35.3% of cases with artificial access (P = .016), and 11.3% of cases with wrist access compared with 25.7% of cases with elbow access (P = .049). Spontaneously closed AV accesses tended to have a lower mean access flow compared with functioning accesses (P = .019). On multivariate analysis, female sex and AV access flow volume affected spontaneous AV access closure (odds ratio 4.749, 95% confidence interval 1.919-35.383, P = .008; odds ratio 0.998, 95% confidence interval 0.996-0.999, P = .010, respectively). CONCLUSIONS: Our results suggest that AV access thrombosis occurs more frequently during the early postoperative period, particularly in female patients or patients with low flow access, whereas it is a rare event in male patients or patients with high access flow, especially in the late postoperative period.