Pairs Of Kidneys Research Articles

Contribution of organ vasculature in rat renal analysis for ochratoxin a: relevance to toxicology of nephrotoxins.

Assumptions surrounding the kidney as a target for accumulation of ochratoxin A (OTA) are addressed because the contribution of the toxin in blood seems invariably to have been ignored. Adult rats were maintained for several weeks on toxin-contaminated feed. Using standard perfusion techniques, animals were anaesthetised, a blood sample was taken, one kidney was ligated, and the other kidney perfused with physiological saline in situ under normal blood pressure. Comparative analysis of OTA in pairs of kidneys showed marked reduction in the perfused organ in the range 37%–98% (mean 75%), demonstrating the general efficiency of perfusion supported also by histology, and implying a major role of blood in the total OTA content of kidney. Translation of OTA values in plasma to whole blood, and its predicted contribution as a 25% vascular compartment in kidney gave values similar to those in non-perfused kidneys. Thus, apparent ‘accumulation’ of OTA in kidney is due to binding to plasma proteins and long half-life in plasma. Attention should be re-focused on whole animal pharmacokinetics during chronic OTA exposure. Similar principles may be applied to DNA-OTA adducts which are now recognised as occurring in blood; application could also extend to other nephrotoxins such as aristolochic acid. Thus, at least, quantitative reassessment in urological tissues seems necessary in attributing adducts specifically as markers of potentially-tumourigenic exposure.

The Impact of Donor Viral Replication at Transplant on Recipient Infections Posttransplant

Organ donors are often implicated as the source of posttransplant recipient infection. We prospectively studied kidney and liver donor-recipient pairs to determine if donor viral replication of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and BK polyomavirus (BKV) at transplant was a risk factor for posttransplant recipient infection and disease. Donors and recipients were studied for antibodies against CMV and EBV and for quantitative viral replication of CMV, EBV, and BKV in oral washes, urine, and whole blood pretransplant. Recipient testing continued every 3 months after transplantation. Demographic and clinical data on infections and graft and subject outcomes were obtained. The 98 donor-recipient pairs included 15 liver and 83 kidney transplants (18 of whom were children). No donor had detectable CMV replication; therefore, its impact on recipient CMV replication could not be analyzed. Donor EBV replication occurred in 22%, mostly in the oral wash and showed no impact on posttransplant recipient EBV replication (P=0.9) or EBV viremia (P=0.6) in kidney or liver recipients. Donor BKV replication occurred in 17%, mostly in the urine and although not associated with posttransplant recipient urinary BKV replication in recipients, it was associated with BKV viremia (P=0.02), and a significantly shorter time to BKV viremia (P=0.01) in kidney recipients. Donor replication of CMV or EBV did not impact posttransplant recipient viral replication in kidney or liver transplants. Donor urinary BKV replication is associated with recipient BKV viremia in kidney transplants.

Correlation between Ultrasonographically- Measured Bi-polar Length of Kidneys with Body Length and Body Weight in Yankasa Ewes (Ovisaries)

The aim of the study was to determine the correlation between ultrasonographically-measured bipolar length of kidneys with body length and body weight in Yankasa ewes (Ovisaries). A total of 27 apparently healthy ewes weighing between 18-35kg were used for the study. The body lengths of the ewes were measured in inches using a piece of string from the level of the nostrils to the base of the tail. The string was stretched out against a measuring tape and the values obtained were entered into a record book. The paired kidneys of each ewe were scanned in turn through the shaved left paralumbar fossa and the measured bipolar kidney lengths were also recorded. The results obtained showed a positive correlation between the kidney bipolar length and the body length (P<0.05) and a positive correlation between kidney lengths with the body weight the strength of which was lower than that between the kidney length and body length.

Arquitetura e estrutura dos rins de Gracilinanus microtarsus (Didelphimorphia: Didelphidae) (WAGNER, 1842)

Gracilinanus microtarsus is a South American marsupial that belongs to Didelphimorphia order and Didelphidae family. The gross and microscopic anatomy of the kidneys of G. microtarsus was studied. The species has a pair of kidneys located in the sublumbar region of the abdominal cavity, close to the spine. The right kidney is cranial to the left kidney, and both have a bean shape. In a longitudinal cut, the kidney has defined areas, such as the renal cortex and medulla, as well as the renal papilla, calices and renal pelvis. The kidney of Gracilinanus microtarsus is classified as unilobado with a smooth surface and showing microscopic aspect similar to the kidneys of dogs and cats.

English

Address for Correspondence: Shaik Hussain Saheb, Assistant Professor of Anatomy, JJM Medical College, Davangere, Karnataka, India. Mobile +91-9242056660. E-Mail: anatomyshs@gmail.com Access this Article online Quick Response code Web site: 1 Assistant Professor of Anatomy, Travancore Medical College, Kollam, Kerala, India. 2 Professor of Anatomy, JSS Medical College, Mysore, Karnataka, India. 3 Assistant Professor of Physiology, Travancore Medical College, Kollam, Kerala, India. *4 Assistant Professor of Anatomy, JJM Medical College, Davangere, Karnataka, India. Background: Based on vascular divisions the renal tissue divided into five segments that are apical, anterior superior, anterior inferior, inferior and posterior. The apical segment occupies the antero medial region of the superior pole. The superior segment includes the rest of the superior pole and the central antero-superior region. The segmental arteries of the kidney supply the organ in such a way that, each renal pole receives its own artery while, the anterior portion between the poles is supplied by an upper and lower segmental vessel. The present study concentrated on variation of superior segmental artery which is help in nephrology clinical practice. Materials and Methods: Fifty pairs of kidneys with intact abdominal aorta and renal artery were collected from the dead bodies obtained from the mortuary of Forensic department, JSS Medical College and Mysore Medical College and studied in JSS Medical College. For study of segmental variation Corrosion cast technique method was used. Results: In present study type I superior segmental artery were found in 28%, type II in 12%, type III in 14%, type IV 20%, type V in 1% o and type VI 23% of cases. Conclusions: We observed variations in superior segmental branch of renal artery in 100 kidneys and observed 6 types of variation. These knowledge of vascular segments of kidney helpful for the clinician to do renal transplantation interventional radiological procedures.

Generic Formulation of Mycophenolate Mofetil (Myfenax) in De Novo Renal Transplant Recipients: Results of 12-Month Observation

BackgroundThe aim of this study was to show the preliminary outcomes of transplantation in patients treated with the generic formulation of mycophenolate mofetil (Myfenax, Teva). Materials and MethodsOver the past 4 years, 60 patients received generic mycophenolate mofetil (Myfenax) after renal transplantation at the Gdansk Transplantology Center. During the same time period, another 273 kidney transplantations were performed in our department, and these patients were treated with other formulations of mycophenolate (CellCept [Roche], Myfortic, or mycophenolate mofetil–Apotex) as a part of the immunosuppressive plan. Thirty of the Myfenax patients received a pair of kidneys from the same donor and received original mycophenolate mofetil CellCept with observation for at least 12 months. ResultsThe outcomes of the renal transplantations in both groups (Myfenax vs pair) were good, with satisfactory function of grafts. One case of graft loss was reported in the Myfenax group (renal vein thrombosis, graftectomy 5 days after transplantation). There was no difference in the incidence of acute renal graft rejection in either group. Moderate adverse reactions to immunosuppression were observed in both groups. On the other hand, a comparison between the 60 patients with Myfenax and the 273 other patients with other formulations of mycophenolate revealed no differences in the incidence of acute renal graft rejection, delayed graft function, graft loss, and death. ConclusionsThere were no differences in the incidence of acute renal graft rejection, delayed graft function, graft loss, and death in patients with Myfenax vs original CellCept and other formulations of mycophenolate. To confirm its complete biological and pharmacokinetic equivalence with the reference medicine, long-term, randomized observations carried out on larger renal transplant patients groups are needed.

Preemptive Kidney Transplantation: Analysis of Kidney Grafts From the Same Donor

BackgroundFrom November 2003 to December 2012, in the Gdańsk Center, 64 patients received preemptive transplantation (PET). PET comprised 8% of 794 kidney transplantations performed during this time. The benefits for individual patients and for the health care system are discussed. MethodsThis study compares the outcomes of these PET patients who had their kidney pairs transplanted after a variable duration of dialysis (PTD), a total of 51 pairs. ResultsThe mean Charlson comorbidity index was 2.57 vs 3.04 (P > .05) for the PET and PTD groups, respectively. Both groups did not differ significantly with respect to 1-year patient and graft survivals, and incidences of acute rejection. Five (9.8%) PET patients and 20 (39%) PTD patients experienced delayed graft function (P < .05). The graft function (serum creatinine/4p MDRD) 1 year after transplantation was similar in both groups (1.42/53.7 vs 1.43/57.4; mg/dL/mL/min/1.73 m2). More PET patients continued normal professional activities or education before and after transplantation (P < .05). ConclusionsOur single-center results confirmed that for both medical and socioeconomic reasons, PET is an optimal mode of renal replacement therapy.

Effect of HCV, HIV and Coinfection in Kidney Transplant Recipients: Mate Kidney Analyses

Reports of kidney transplantation (KTX) in recipients with hepatitis C virus (HCV+), human immunodeficiency virus (HIV+) or coinfection often do not provide adequate adjustment for donor risk factors. We evaluated paired deceased-donor kidneys (derived from the same donor transplanted to different recipients) in which one kidney was transplanted into a patient with viral infection (HCV+, n = 1700; HIV+, n = 243) and the other transplanted into a recipient without infection (HCV- n = 1700; HIV- n = 243) using Scientific Registry of Transplant Recipients data between 2000 and 2013. On multivariable analysis (adjusted for recipient risk factors), HCV+ conferred increased risks of death-censored graft survival (DCGS) (adjusted hazard ratio [aHR] 1.24, 95% confidence interval [CI] 1.04-1.47) and patient survival (aHR 1.24, 95% CI 1.06-1.45) compared with HCV-. HIV+ conferred similar DCGS (aHR 0.85, 95% CI 0.48-1.51) and patient survival (aHR 0.80, 95% CI 0.39-1.64) compared with HIV-. HCV coinfection was a significant independent risk factor for DCGS (aHR 2.33; 95% CI 1.06, 5.12) and patient survival (aHR 2.88; 95% CI 1.35, 6.12). On multivariable analysis, 1-year acute rejection was not associated with HCV+, HIV+ or coinfection. Whereas KTX in HIV+ recipients were associated with similar outcomes relative to noninfected recipients, HCV monoinfection and, to a greater extent, coinfection were associated with poor patient and graft survival.

A Prospective Randomised Paired Trial of Sirolimus versus Tacrolimus as Primary Immunosuppression following Non-Heart Beating Donor Kidney Transplantation

Introduction: With calcineurin inhibitors potentiating damage from ischaemia-reperfusion injury in kidneys from donors after cardiac death we wanted to investigate the role of substituting sirolimus for tacrolimus in the delayed introduction of calcineurin inhibitor regime used in our centre. Method: A prospective randomised paired open-label study was performed taking pairs of kidneys from each donor and randomising one to a tacrolimus-based regime and the other to a similar regime based on sirolimus. Graft function at one year was the primary endpoint. Results: Total 31 pairs of kidneys were randomised to each group, with 19 pairs of recipients available for analysis after post-randomisation study exclusions. Despite a higher incidence of biopsy proven acute rejection in the sirolimus group, renal allograft function was similar in both groups at three-monthly intervals up to one year post-transplant. All episodes of acute rejection in the sirolimus group occurred in the first three months. Graft and patient survival at one year was 100% in the tacrolimus group, with one death with functioning graft in the sirolimus group (95% survival). Unfortunately, 10 of the 19 patients in the sirolimus arm required switch of medication to tacrolimus due to acute rejection or intolerable drug side effects. Conclusions: Graft survival and function were very similar in the two groups despite the higher rate of acute rejection in the sirolimus arm, raising the possibility that the damage done by acute rejection was adequately offset by the nephron-sparing effect of sirolimus compared to tacrolimus. Sirolimus may have a role as a longer-term maintenance immunosuppressant after initial treatment with a different agent such as tacrolimus or belatacept.

Donation after Cardiac Death Pediatric En Bloc Renal Transplantation

Use of small pediatric kidneys obtained from extremely young donors after cardiac death has been limited. This potential organ source remains under used by transplant teams. We reviewed all renal transplants at our institution from 2000 to 2013 to identify recipients of an en bloc pair of kidneys from deceased pediatric donors younger than 4 years. The outcomes of donation after cardiac death en bloc allografts were compared with neurological determination of death en bloc allografts. A total of 21 recipients of en bloc renal allografts were identified, of which 4 organ pairs were obtained through donation after cardiac death. Mean ± SD donor age was 20.6 ± 11.6 months and weight was 12.4 ± 3.7 kg. Delayed allograft function occurred in 2 of 4 recipients of allografts obtained from donation after cardiac death en bloc and 3 of 17 recipients of allografts from neurological determination of death en bloc. One year after transplantation mean ± SD glomerular filtration rates were similar, at 80.7 ± 15.3 and 85.7 ± 33.4 ml/minute/1.73 m(2) in the cardiac and neurological allograft groups, respectively (difference not significant). Surgical complications occurred in 3 patients, and no allograft was lost to thrombosis. We report successful transplantation of a small cohort of pediatric en bloc kidneys obtained through donation after cardiac death from donors younger than 4 years. Outcomes at 1 year are comparable to those in neurological determination of death en bloc allograft recipients.

What Goes Wrong With Mitochondria During Renal Cold Storage Plus Transplantation and Can It Be Fixed?

Purpose: The overall goal of this study is to elucidate mechanisms involved with cold storage (CS) mediated mitochondrial and renal injury, which could lead to better therapies (or preservation solutions) that are designed to minimize damage, increase the donor pool, and improve renal transplant outcomes. Our published reports showed that cold storage induces mitochondrial and renal damage, and we recently reported that a mitochondrial targeted antioxidant, MitoQ, blunted mitochondrial damage in a porcine kidney model. Mitochondrial damage can be alleviated by biogenesis of new healthy mitochondria; however, few studies have investigated the mitochondrial biogenesis pathway during renal CS + transplantation. Methods: Male rat kidneys were isolated and cold stored for 0-18 hr +/- MitoQ (100 uM) followed by transplantation. Mitochondrial function (oxygen consumption) was assessed via high resolution respirometry and ATP measurement of renal biopsies post-transplant (18 hr). Quantitative proteomics of mitochondrial extracts separated using blue native gel electrophoresis was used as a proteomic approach to identify key mitochondrial respiratory complex proteins altered during CS + transplantation. Mitochondrial biogenesis was assessed by small fragment PCR of mitochondrial DNA (mtDNA) as well as mitochondrial protein expression. Pilot studies using ‘discarded' paired human kidneys obtained from our local procurement office were also treated with MitoQ. Results: Renal CS + transplantation lead to decreased mtDNA integrity and copy numbers, reduced respiratory complex I and II/III function, and impaired mitochondrial biogenesis. Quantitative proteomics of complex I showed that 8 complex I subunits were decreased following CS + transplantation. We also showed that adding MitoQ increased ATP and mtDNA after CS alone, and improved renal function following CS + transplantation. Early results using discarded human kidneys showed reduced mtDNA integrity and biogenesis in these kidneys; addition of MitoQ restored respiratory complex activity in these kidneys. Summary: These studies suggest cold storage leads to damaged respiratory complexes as well as damage to the mtDNA, which can both lead to reduced mitochondrial function and loss of the reparative biogenesis component. Interestingly, inclusion of MitoQ during cold storage lead to protection against mitochondrial and renal damage during cold storage and transplantation. Supported by NIH DK089659 (LAMC).

Dual Kidney Transplants From Adult Marginal Donors: Double or Nothing.

Dual kidney transplantation (DKT) may reduce organ discard and optimize the use of kidneys from adult marginal donors. Methods: We retrospectively reviewed outcomes in DKT; if the donor creatinine clearance was <65 ml/min, then the kidneys were considered for DKT. Low risk patients (pts) were chosen with informed consent; all received either r-ATG or alemtuzumab induction with tacrolimus/mycophenolate ± steroids. Results: From 11/01-3/13, 72 DKTS were performed including 46 from expanded criteria donors (ECDs), 17 (5 ECD) from donation after cardiac death (DCD) donors, and 9 from standard criteria donors (SCD). A total of 31 kidney pairs (43%) were imported from other donor service areas; cold ischemia times were ≥30 hours in 22 cases (31%). Nearly all kidneys were refused by multiple centers and many were targeted for discard. Mean donor and recipient ages were 60 and 59 years, respectively, including 15 donors and recipients ≥70 years of age. Mean pre-KT waiting and dialysis vintage times were 12 months and 24 months, respectively. Pt and graft survival rates were 85% and 71% with a mean follow-up of 4 years. One year and death-censored graft survival rates were 90% and 80%. Outcomes did not differ by donor source or recipient age. 11 pts died at a mean of 36 months post-DKT (8 with functioning grafts) and 13 experienced graft loss at a mean of 34 months. The incidence of delayed graft function (DGF) was 24%; there were 2 cases (2.8%) of primary nonfunction. Mean length of initial hospital stay was 7.6 days. The 12 month incidences of surgical complications, acute rejection (AR), and major infection were each 17%. Mean serum creatinine and aMDRD GFR levels at 24 months were 1.5 mg/dl and 51 ml/min. Graft survival was comparable to concurrent single ECD and graft function comparable to concurrent SCD KTs. In the absence of DGF or AR, the proportionate nephron mass transplanted from donor to DKT recipient was 77% compared to 55-58% for pts receiving single KTs from SCD, ECD, or DCD donors. Conclusions: DKT using kidneys from marginal donors that otherwise might be discarded offer a viable option to counteract the growing shortage of single kidneys. Acceptable medium-term outcomes can be achieved with limited nephron mass donors with appropriate donor and recipient selection.

Do we need a different organ allocation system for kidney transplants using donors after circulatory death?

BackgroundThere is no national policy for allocation of kidneys from Donation after circulatory death (DCD) donors in the UK. Allocation is geographical and based on individual/regional centre policies. We have evaluated the short term outcomes of paired kidneys from DCD donors subject to this allocation policy.MethodsRetrospective analysis of paired renal transplants from DCD’s from 2002 to 2010 in London. Cold ischemia time (CIT), recipient risk factors, delayed graft function (DGF), 3 and 12 month creatinine) were compared.ResultsComplete data was available on 129 paired kidneys.115 pairs were transplanted in the same centre and 14 pairs transplanted in different centres. There was a significant increase in CIT in kidneys transplanted second when both kidneys were accepted by the same centre (15.5 ± 4.1 vs 20.5 ± 5.8 hrs p < 0.0001 and at different centres (15.8 ± 5.3 vs. 25.2 ± 5.5 hrs p = 0.0008). DGF rates were increased in the second implant following sequential transplantation (p = 0.05).ConclusionsPaired study sequential transplantation of kidneys from DCD donors results in a significant increase in CIT for the second kidney, with an increased risk of DGF. Sequential transplantation from a DCD donor should be avoided either by the availability of resources to undertake simultaneous procedures or the allocation of kidneys to 2 separate centres.

Development, damage and repair of the mammalian kidney (208.1)

The paired kidneys are vital organs controlling water, salt and pH balance for body fluids, removal of toxic by‐products of metabolism, the pressure and composition of blood, and bone formation. The functional unit of the kidney is the nephron. Depending on the mammalian species, 10’s to hundreds of thousands of nephrons are generated during a lengthy period of fetal life. Low nephron number has emerged as a risk factor for development of kidney disease, and due to an absence of a postnatal nephrogenic program, repair of existing nephrons is the endogenous strategy for restoring function to severely damaged kidneys. A deep understanding of nephron formation, damage and repair, will facilitate and prime the development of knowledge‐based strategies to treat the rising burden of kidney disease. I will discuss our current efforts towards this long‐term goal through the molecular and cellular dissection of nephron stem/progenitor programs during fetal life, and the nephron repair processes initiated on acute kidney injury.

Numerical study of film cooling from converging slot-hole on a gas turbine blade suction side

A numerical research on the film cooling performance of a single row of converging slot-holes (console) on the blade suction side in an engine-simulated environment was carried out, in which the Reynolds number was arranged from 400,000 to 600,000 and the blowing ratio was arranged from 0.5 to 3. A comparison in contrast to a cylindrical hole was made and the effects of major factors on the film cooling effectiveness and aerodynamic loss were explored, including the film hole location, blowing ratio and primary flow Reynolds number. For the console cooling geometry, the interaction between the coolant jet from inclined console and the mainstream flow results in secondary vortices with a sense of rotation opposite to the kidney pair, which makes the coolant jet from the console be of the flow mechanism for suppressing normal penetration. Additional corner vortices are also observed in the intersection of two consoles on the convex surface. When the film holes are located upstream of the channel throat, the level of aerodynamic loss for the console is obviously less than the cylindrical holes. At higher blowing ratios, more coolant jet momentum is transferred to the tangent and lateral flow of the coolant jet issued from the consoles, resulting in a film cooling enhancement. The console row shows great potential in the blade film cooling application, especially favorable when it is located upstream of the channel throat.

Morphogenesis of Rabbit Kidney Pre-and Postnatal

Mammalian renal development differs from that of most of the other organs in that it proceeds through a series of three successive phases, each is marked by the formation of a more complex pair of kidneys. These kidneys are called the pronephros, mesonephros, and metanephros. The current study has been conducted to elucidate the developmental changes of rabbit kidneys during their pre- and postnatal life. In the present study we used samples, at different ages, of the rabbit kidneys from embryonic day 15 (E15) till maturity for light and scanning electron microscopical investigation. At E15, large mesonephros, occupied a great part of abdominal cavity of rabbit embryo, and undifferentiated metanephros were noticed. At E19 metanephros became differentiated into cortex and medulla with the initiation of nephron-forming stage. Additionally at this stage, the caudal series of mesonephros still detected but in degenerated and atrophied structure. Just before birth, at E30, the kidney demonstrated well-developed renal corpuscles, differentiated proximal and distal convoluted tubules, with apparently detectable loop of Henle and large collecting ducts. Shortly after birth rabbit kidney showed further morphogenesis and at two-months old, the kidney of rabbit with mature histological structure of the renal parenchyma was documented. In conclusion, the development of rabbit kidneys occurred mainly during the prenatal period while their histological maturity occurred from two to three weeks after birth. The present findings were discussed with previous publications.

Identifying Potential Kidney Donors Among Newborns Undergoing Circulatory Determination of Death

Over 96,000 patients await kidney transplantation in the United States, and 35,000 more are wait-listed annually. The demand for donor kidneys far outweighs supply, resulting in significant waiting list morbidity and mortality. We sought to identify potential kidney donors among newborns because en bloc kidney transplantation donation after circulatory determination of death (DCDD) may broaden the donor pool. We reviewed discharges from our 84-bed NICU between November 2002 and October 2012 and identified all deaths. The mode of death among potential organ donors (weight ≥ 1.8 kg) was recorded. Patients undergoing withdrawal of life support were further evaluated for DCDD potential. After excluding patients with medical contraindications, those with warm ischemic time (WIT) less than 120 minutes were characterized as potential kidney donors. There were 11,201 discharges. Of 609 deaths, 359 patients weighed ≥ 1.8 kg and 159 died after planned withdrawal of life support. The exact time of withdrawal could not be determined for 2 patients, and 100 had at least 1 exclusion criterion. Of the remaining patients, 42 to 57 infants were potential en bloc kidney donors depending on acceptance threshold for WIT. Applying a 40% to 70% consent rate range would yield 1.7 to 4 newborn DCDD donors per year. A neonatal DCDD kidney program at our institution could provide 2 to 4 paired kidneys for en bloc transplantation each year. Implementing a DCDD kidney donation program in NICUs could add a new source of donors and increase the number of kidneys available for transplantation.

Single Center Experience with Deceased Donor Kidney Transplantation in Patients Aged 70 and Older: A Matched-Pair Cohort Study

The purpose of this study was to compare mate deceased donor (DD) kidney transplant (KT) outcomes in patients ≥70 versus <70 years of age in a matched-pair analysis. Methods: Single center retrospective review of adult KT cases. Results: From 5/03 to 3/12, we identified 33 DD kidney pairs that met the above criteria. Mean donor age and BMI were 52 years and 27.4 kg/m2, respectively, including 19 (58%) expanded criteria donors. Mean recipient ages were 73.6 and 55.3 years in the 2 groups (p 75), and 3% in all 33 younger patients (p=0.02 compared to those >75). The timing of DWFG was at a mean of 40.5 months in patients aged 75 and older compared to 72 months for those aged 70-74 years. Conclusions: When controlling for donor factors in a paired kidney analysis, medium-term outcomes are largely influenced by a higher incidence of DWFGs in the elderly, particularly in patients aged 75 and older.

Fusion of ERT images based on Dempster-Shafer’s evidence theory

In this paper, an electrical resistance tomography (ERT) imaging method is used as a classifier, and then the Dempster-Shafer’s evidence theory with fuzzy clustering is integrated to improve the ERT image quality. The fuzzy clustering is applied to determining the key mass function, and dealing with the uncertain, incomplete and inconsistent measured imaging data in ERT. The proposed method was applied to images with the same investigated object under eight typical current drive patterns. Experiments were performed on a group of simulations using COMSOL Multiphysics tool and measurements with a piece of porcine lung and a pair of porcine kidneys as test materials. Compared with any single drive pattern, the proposed method can provide images with a spatial resolution of about 10% higher, while the time resolution was almost the same.

Correlation Between Dual Kidney Biopsy in Expanded-Criteria Donors and Transplant Survival

ObjectiveThe aim was to study the relation between same-donor renal biopsies and analyze whether the score influences graft survival. MethodsWe retrospectively reviewed histologic results of expanded-criteria donors and the graft survival in patients followed at Reina Sofia Hospital (Cordoba, Spain) from January 2004 to October 2012. We analyzed clinical and demographic variables from the donors, as well the association between the scores of same-donor biopsies who had different scores for each kidney and the graft survival with a t test for paired data. A Kaplan-Meier with log-rank test was performed between the higher-score and the lower-score groups. We excluded retransplantation and those who received a combined transplantation (liver or pancreas). ResultsWe analyzed 168 kidneys that had been biopsied, from 84 donors. Of the whole sample, 35.7% (n = 30) had the same score for each kidney, whereas 64.3% (n = 54) had discrepancies. In this second group, 81.8% (n = 44) had a difference of 1 point, and the remaining 18.2% (n = 10) had a larger difference. Both kidneys were suitable for transplantation in 72.7% of cases (n = 40), only 1 in 14.5% (n = 8), and none in 12.7% (n = 7). For analyzing the survival of the paired kidneys there were 48 kidneys from 24 donors with a different score for each kidney. We observed a difference in favor of the better scores, with a difference of 11 months up to the time of the analysis (P = .045). We found no significant differences in the log-rank test between the survival rate for the group with a less favorable score (95% confidence interval [CI], 61.26–95.67) versus those with a more favorable score (95% CI, 66.76–93.03). ConclusionsA high percentage of biopsies had a different score for the 2 kidneys from the same donor. This difference was important for graft survival. We therefore recommend doing a biopsy of both kidneys.