Early corticosteroid avoidance in kidney transplant recipients receiving ATG-F induction: 5-year actual results of a prospective and randomized study.

One hundred ninety-seven patients received anti-T-lymphocyte globulins Fresenius, mycophenolate mofetil and delayed cyclosporine, and were randomized to ≥6-month corticosteroids (+CS; n=99) or no CS (-CS; n=98). One- and five-year actual graft survival (censored for death) was 93.2% and 86.4% in the +CS group versus 94.9% and 89.8% in the -CS group (5-year follow-up, p=0.487). Freedom from clinical rejection was 86.9% and 81.8% versus 74.5% and 74.5% (p=0.144), respectively, at 1 and 5 years; 5-year freedom from biopsy-proven rejection was 88.9% versus 83.7% (p=0.227). More late first rejections occurred in the +CS group. Significantly lower 5-year graft survival in patients experiencing rejection was observed for +CS (55.6% vs. 92.0%; p=0.005) with 8/18 versus 2/25 graft losses. Renal function at 5 years was stable and comparable (median serum creatinine, 159 vs. 145 µmol/L; creatinine clearance, 53.5 vs. 56.6 mL/min). More +CS patients developed diabetes, dyslipidemia and malignancies. Rejections in -CS patients occurred early after transplantation and did not impair long-term renal function. In patients receiving CS, rejections occurred later and with a higher risk for subsequent graft failure. A similar and not inferior 5-year efficacy profile and a reduced morbidity were observed in CS-free patients compared to patients who received CS for at least 6 months.

Complement genes strongly predict recurrence and graft outcome in adult renal transplant recipients with atypical hemolytic and uremic syndrome.

Atypical hemolytic and uremic syndrome (aHUS) is a severe disease strongly associated with genetic abnormalities in the complement alternative pathway. In renal posttransplantation, few data are available on recurrence risk and graft outcome according to genetic background in aHUS patients. The aim of this study was to identify risk factors for recurrence and transplant outcome and, in particular, the role of complement gene abnormalities. We retrospectively studied 57 aHUS patients who had received 71 renal transplants. A mutation in complement gene was identified in 39 (68%), in factor H (CFH), factor I (CFI), membrane cofactor-protein (MCP), C3 and factor B (CFB). At 5 years, death-censored graft survival was 51%. Disease recurrence was associated with graft loss (p = 0.001). Mutations in complement genes were associated with higher risk of recurrence (p = 0.009). Patients with CFH or gain of function (C3, CFB) mutations had a highest risk of recurrence. M-TOR inhibitor was associated with significant risk of recurrence (p = 0.043) but not calcineurin inhibitor immunosuppressive treatment (p = 0.29). Preemptive plasmatherapy was associated with a trend to decrease recurrence (p = 0.07). Our study highlights that characterization of complement genetic abnormalities predicts the risk of recurrence-related graft loss and paves the way for future genetically based individualized prophylactic therapeutic strategies.

PRODIG (Prevention of new onset diabetes after transplantation by a short term treatment of Vildagliptin in the early renal post-transplant period) study: study protocol for a randomized controlled study.

BACKGROUND: Post-transplant diabetes is a frequent and serious complication of kidney transplantation. There is currently no treatment to prevent or delay the disease. Nevertheless, identification of risk factors make it possible to target a population at risk of developing de novo diabetes. We hypothesized that a short-term treatment with vildagliptin may prevent new onset diabetes after transplantation (NODAT) in high-risk patients. METHODS/DESIGN: This is a multicenter, double-blind, placebo-controlled randomized clinical trial. Patients undergoing first kidney transplantation will be included from ten French transplant centers. Included patients will be randomized (1:1) to receive either vildagliptin 100 or 50 mg/day (depending on glomerular filtration rate) during 2 months (the first dose being administered before entering the operating theatres) or placebo. Additional antidiabetic therapy could be administered according to glycemic control. The primary outcome is the proportion of diabetic patients 1 year after transplantation, defined as patients receiving a diabetic treatment, or having a fasting glucose above 7 mmol/l, and/or with an abnormal oral glucose tolerance test. Secondary outcomes include glycated hemoglobin, the occurrence of acute rejection, infection, graft loss and patient death at 3 months, 6 months, and 12 months after transplantation. Outcomes will be correlated to clinical and general characteristics of the patient, cardiovascular history, nephropathy, dialysis history, transplantation data, biological data, health-related quality of life, and the cost-effectiveness of prevention of diabetes with vildagliptin. DISCUSSION: We have scarce data on the pharmacological prevention of post-transplant diabetes. If our hypothesis is verified, our results will have a direct application in clinical practice and could limit diabetes-associated morbidity, reduce cardiovascular complications, increase quality of life of renal transplant patients, and consequently promote graft and patient survival. Our results may possibly serve for non-transplant patients carrying a high-risk of diabetes associated with other co-morbidities. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02849899 . Registered on 8 February 2016.

Two-year results of renal transplantation in kidney recipients from > or = 65-year-old deceased donors: a French region experience.

The use of elderly deceased donors requires refining criteria for both the donor and the recipient. This report attempted to identify parameters susceptible to further improvement. This retrospective multicenter study analyzed the outcomes of kidney recipients from 15 consecutive elderly deceased donors in the south French region (IR9). Donors were 65 to 74 years old. Mean creatinine clearance was 80 mL/min/1.73 m(2). The donor risk factors for allograft dysfunction were stroke, hypertension, cardiovascular disease, cardiac death, smoking, arrhythmia, and diabetes. The recipients were 35 to 70 years old. The median cold ischemia time was 24 hours. Four patients (16%) suffered delayed graft function (DGF). Three recipients (12%) died within the first 2 months after transplantation. The postoperative complications (29%) were 2 renal artery thromboses, 4 renal artery stenoses, and 1 toe ischemia. Two years after transplantation, their mean serum creatinine was 157 micromol/L. The patient and graft survivals were 88% and 70%, respectively. These results seemed worse than those reported in the literature, but it was a small cohort and a new experience. DGF is probably linked to improvable management to reduce cold ischemia time. The elevated rate of surgical complications might be related to a lack of experience in donor and recipient evaluations. Kidney transplantation from elderly donors requires an efficient organization and an accurate evaluation of both donor renal function and recipient cardiovascular state.

Recurrence of hemolytic uremic syndrome after renal transplantation.

Non-Shiga toxin-associated hemolytic uremic syndrome (non-Stx-HUS) is a rare disease. The clinical outcome is often unfavorable: 50% of patients progress to end-stage renal failure. Several mutations in complement regulatory genes predispose to non-Stx-HUS. Transplantation outcomes are poor among patients with either mutation in the genes encoding complement H or I factors, with 80% graft loss due to HUS recurrence. In contrast, patients with mutation in the gene encoding MCP have no disease relapse after transplantation. There are no treatment guidelines for non-Stx-HUS recurrence. Herein we have presented 8 patients with non-Stx-HUS recurrence after transplantation during the last 10 years in the South of France. HUS recurrence, which occurred early after transplantation in all but 1 patient, was treated by plasma exchange (PE) with substitution by fresh frozen plasma (FFP). Three patients still treated with long-term plasma therapy have no recurrence at 15, 19, or 24 months. An international registry would help to define new guidelines.

Genetic effects of photoadducts and photocross-links in the DNA of phage lambda exposed to 360 nm light and tri-methylpsoralen or khellin.

The furocoumarin, 4,5',8-trimethylpsoralen, sensitizes cells and viruses to 360 nm light, producing cross-links and monoadducts in their DNA. The furanochromone khellin is a less effective sensitizing agent than psoralen, but has been found to induce cross-links and adducts in DNA also. The number of cross-links increases as the square of the time of exposure to light. We found that greater fluences were required for khellin than for psoralen, possibly because of the less favorable angle of the distal unsaturated bonds for corss-linking pyrimidines in adjacent base pairs. By adjusting the time of exposure to 360 nm light, lambda phages were damaged with [3H]psoralen and [3H]khellin so as to produce equal numbers of cross-links. These exposures were found to produce 8-times more [3H]khellin than [3H]psoralen adducts in the DNA of the phages. Similar exposures were made with nonradioactive photosensitizers to determine the effectiveness of lambda phages carrying cross-links and monoadducts in producing genetic recombinants. Lambda phage-prophage genetic corsses were performed with psoralen and khellin-damaged phages under repressed conditions in which replication of the damaged DNA was blocked. It was estimated from the results that cross-links were about 20-times more effective than monoadducts for inducing recombination under repressed conditions. In tests on the survival of plaque forming ability on wild type bacteria, it was estimated that cross-links were about 15-times more effective than the adducts. The results support the conclusion that, in homoimmune crosses with psoralen-damaged lambda phages infecting wild type lysogens, more than three-quarters of the induced recombination can be attributed to cross-links rather than to monoadducts.

Interstrand crosslinks in DNA of phage lambda after exposure to 8-methoxypsoralen and trimethylpsoralen in the presence of light.

Two medically useful photosensitizing furocoumarins, 8-methoxypsoralen (8-MOP) and 4,5'8-trimethylpsoralen (TMP) were compared with respect to their abilities to produce interstrand crosslinks in DNA. DNA from bacteriophage lambda, labeled with 32P, was subjected to sedimentation in alkaline sucrose gradients following exposure to several concentrations of 1 of the 2 psoralens and irradiation (UV-A, 360 nm) for various times. In alkaline sucrose gradients, crosslinked DNA molecules sediment about 1.4 times faster than undamaged DNA strands and the proportion of molecules carrying crosslinks can be estimated with reasonable accuracy. At equimolar psoralen concentrations (2 x 10(-7)M, or 4 x 10(-5)M) and with increasing irradiation times, the rate of production of crosslinked DNA was 4 to 30 times greater for TMP than for 8-MOP. Differences in the therqpeutic efficacy of 8-MOP and TMP in various clinical situations may be accounted for by the types of photoadducts formed by each drug as well as by their solubilities, rates of absorption and rates of metabolic degradation.

Radiographic follow-up of a phalangeal brown tumor.

We report the 6-year radiographic follow-up of a phalangeal brown tumor in a patient with severe hyperparathyroidism secondary to chronic renal failure treated with hemodialysis. The phalangeal lesion increased in size during the first 3 years, until the patient finally accepted to undergo parathyroidectomy. The initial radiographic change was a small intracortical lytic area. Two years later, an expansile cystic lesion was visible in the phalanx, and computed tomography showed a cortical defect. Ossification of the lesion occurred over the 2.5 years following parathyroidectomy. The epidemiology, radiographic changes and post-treatment evolution of brown tumor in dialysed patients is reviewed. Surgical parathyroidectomy is the standard treatment for brown tumor complicating secondary hyperparathyroidism. The usefulness and limitations of treatment with vitamin D analogs, recently reported in a few case reports, are discussed.

Epstein-Barr virus-associated hepatic leiomyosarcoma after renal transplantation: case report.

The incidence of neoplastic complications after solid organ transplantation is increasing tremendously probably as the consequence of long term immunosuppression. Beside usual risk factors, the oncogenic role of some viruses like Epstein-Barr virus is well established. We report a case of a primitive EBV-induced liver leiomyosarcoma after renal transplantation.

Long-term glomerular filtration rate in liver allograft recipients according to the type of calcineurin inhibitors.

The calcineurin inhibitors (CNI) cyclosporine micro emulsion (CyA-ME) and tacrolimus (Tac) both display renal and vascular toxicities. We undertook a single-center retrospective study among 149 surviving liver transplant recipients. The primary outcome was kidney function over 10 years posttransplant, evaluating the glomerular filtration rate (GFR) by the abbreviated Modification of Diet in Renal Disease formula with subsequent Kidney Disease Outcomes Quality Initiative staging. The secondary outcomes included correlations between CNI trough levels (C0), GFR, and items of cardiovascular toxicity. At 1 and 5 years, the mean GFRs were 74.2 and 76.9 mL/min/1.73 m(2) under Tac versus 62.8 and 66.0 mL/min/1.73 m(2) under CyA-ME (P < .001). The mean value in favor of Tac was + 10 mL/min/1.73 m(2). Distribution of GFR stages showed more Tac patients at stage 1 or 2 and more at stage 4 or 5 under CyA-ME. There was no significant correlation between CNI-C0 and GFR. Switches between CNI or to mycophenolate mofetil did not show any significant GFR improvement. Patients under CyA-ME displayed significantly higher blood pressures with 3 requiring dialysis versus none under Tac. In conclusion, we observed that liver transplant patients under Tac maintained significantly better renal function with less progression to dialysis as compared with CyA-ME, indicating a lower renal and vascular (lower BP) toxicity.

Formation of covalently closed heteroduplex DNA by the combined action of gyrase and RecA protein.

The concerted action of DNA gyrase and RecA protein of Escherichia coli on intact and gapped homologous or partially homologous plasmid DNA molecules leads to the formation of covalently closed DNA containing one strand of each parental molecule. Large regions of non-homology can be incorporated into the closed circular duplex. Both proteins are essential for the reaction to take place, and type I topoisomerase cannot substitute for DNA gyrase.

Role of base-pairing in the control of an enzyme reaction.

In an attempt to ascertain whether specific base-pairing could have a regulating function in an enzyme system in which nucleotides serve as the substrate, we studied the effects of the addition of the various homopolymers of the ribonucleotide series on the action of adenylate kinase on ADP or CDP, and found that the results support this possibility. Poly U strongly inhibits the enzyme action on ADP, and poly G that on CDP, both to the extent of about 70 per cent. Lesser effects are shown when poly G is used with ADP and poly U with CDP. The other homopolymers tested, poly A and poly C, are ineffective.

Translational complementarity of RNA transcripts of native and denatured B. subtilis DNA.

Previous evidence has suggested that the L and H fractions into which denatured DNA of B. subtilis can be separated by chromatography are complementary to each other with regard to base compositon, nucleotide sequence, and template properties, and that they may be regarded as families of fragments of the respective DNA strands. The present study tests the proposition that these fractions should also exhibit features of translational complementarity with respect to the DNA-dependent or the RNA-dependent incorporation of amino acids into ribosomes. This has been shown to be the case with the use of two pairs of amino acids: (1) lysine and phenylalanine; (2) proline and glycine.

The binding of RecA protein to duplex DNA molecules is directional and is promoted by a single stranded region.

RecA protein from E. coli binds more strongly to single stranded DNA than to duplex molecules. Using duplex DNA that contains single stranded gaps, we have studied the protection by RecA protein at various concentrations, of restriction sites as a function of their distance from the single stranded region. We show that the binding of RecA protein, initiated in the single stranded region, extends progressively along the adjoining duplex in the 5' to 3' direction with respect to the single stranded region. The strand exchange reaction is known to proceed in the same direction.

Complementarity of RNA produced by enzymic transcription of native and denatured B. subtilis DNA.

This paper describes the preparation and some of the properties of the RNA specimens synthesized with the aid of the RNA polymerase of E. coli by transcription of the following DNA templates: (a) undenatured B. subtilis DNA (yielding N-RNA); (b) separated strand fractions L and H isolated by chromatography of the denatured DNA on methylated albumin (yielding L-RNA and H-RNA, respectively). The study of the hybridization behavior of the various RNA products showed that N-RNA, though able to form hybrids with either strand, hybridized with H-DNA to twice as great an extent as with L-DNA. The transcripts of the separated L and H fractions exhibited complete specificity with respect to complexing: L-RNA hybridized only with L-DNA, H-RNA only with H-DNA.

Recombination-dependent repair of DNA double-strand breaks with purified proteins from Escherichia coli.

We have developed an in vitro system in which repair of DNA double-strand breaks is performed by purified proteins of Escherichia coli. A segment was deleted from a circular duplex DNA molecule by restriction at two sites. 3' single-stranded overhangs were introduced at both ends of the remaining linear fragment. In a first step, RecA protein catalyzed the formation of a D-loop between one single-stranded tail and a homologous undeleted supercoiled DNA molecule. In a second step, E. coli DNA polymerase II or III used the 3' end in the D-loop as a primer to copy the missing sequences of the linear substrate on one strand of the supercoiled template. Under proper conditions, the integrity of the deleted substrate was restored, as shown by analysis of the products by electrophoresis, restriction, and transformation. In this reaction, DNA synthesis is strictly dependent on recombination, and repair is achieved without formation of a Holliday junction.