The mechanism of covalent inhibition of LAR phosphatase by illudalic acid

Leukocyte antigen-related (LAR) phosphatase is a receptor-type protein tyrosine phosphatase involved in cellular signaling and associated with human disease including cancer and metabolic disorders. Selective inhibition of LAR phosphatase activity by well characterized and well validated small molecules would provide key insights into the roles of LAR phosphatase in health and disease, but identifying selective inhibitors of LAR phosphatase activity has been challenging. Recently, we described potent and selective inhibition of LAR phosphatase activity by the fungal natural product illudalic acid. Here we provide a detailed biochemical characterization of the adduct formed between LAR phosphatase and illudalic acid. A mass spectrometric analysis indicates that two cysteine residues are covalently labeled by illudalic acid and a related analog. Mutational analysis supports the hypothesis that inhibition of LAR phosphatase activity is due primarily to the adduct with the catalytic cysteine residue. A computational study suggests potential interactions between the illudalic acid moiety and the enzyme active site. Taken together, these data offer novel insights into the mechanism of inhibition of LAR phosphatase activity by illudalic acid.

Derivatives of the Fungal Natural Product Illudalic Acid Inhibit the Activity of Protein Histidine Phosphatase PHPT1

PHPT1 is a protein histidine phosphatase that has been implicated in several disease pathways, but the chemical tools necessary to study the biological roles of this enzyme and investigate its utility as a therapeutic target have yet to be developed. To this end, the discovery of PHPT1 inhibitors is an area of significant interest. Here, we report an investigation of illudalic acid and illudalic acid analog-based inhibition of PHPT1 activity. Four of the seven analogs investigated had IC50 values below 5 μM, with the most potent compound (IA1-8H2) exhibiting an IC50 value of 3.4±0.7 μM. Interestingly, these compounds appear to be non-covalent, non-competitive inhibitors of PHPT1 activity, in contrast to other recently reported PHPT1 inhibitors. Mutating the three cysteine residues to alanine has no effect on inhibition, indicating that cysteine is not critical for interactions between inhibitor and enzyme.

Synthesis of illudalic acid and analogous phosphatase inhibitors

Developing an efficient, concise synthesis of the fungal natural product illudalic acid has been a long-standing challenge, made more pressing by the recent discovery that illudalic acid and analogs are selective phosphatase inhibitors. Syntheses of illudalic acid have become progressively more efficient over the decades yet remain strategically grounded in a 17-step synthesis reported in 1977. Here we validate a two-step process-convergent [4 + 2] benzannulation and one-pot coordinated functional group manipulations-for preparing the key trifunctional pharmacophore of illudalic acid. The modular building blocks are readily available in 2-3 steps, for a longest linear sequence (LLS) of 5 steps to illudalic acid from 3,3-dimethylcyclopentanone. A small collection of analogous indanes and tetralins featuring the same pharmacophore were prepared by a similar route. These compounds potently and selectively inhibit the human leukocyte common antigen-related (LAR) subfamily of protein tyrosine phosphatases (PTPs). Evidence supporting a postulated covalent ligation mechanism is provided herein.

[Plan of the day adaptive radiotherapy for bladder cancer: Dosimetric and clinical results]

PURPOSE

To account of individual intra-pelvic anatomical variations in muscle invasive bladder cancer (MIBC) irradiation, adaptive radiotherapy (ART) using a personalized plan library may have dosimetric and clinical benefits.

MATERIAL AND METHODS

The data from ten patients treated for localized MIBC according to the "plan of the day" (P0oD) individualized ART technique were collected and retrospectively analysed. Target volumes and organs at risk (OAR) were delineated at different bladder fill rates, resulting in two or three treatment plans. Daily Cone-Beam CT (CBCT) was used for the selection of PoD at each fraction. Retrospectively, we delineated rectal, intestinal and target volumes on each CBCT, to assess target volume coverage and dose sparing to healthy tissues. A comparison with the conventional radiotherapy technique was performed. The secondary objectives were toxicity and efficacy.

RESULTS

The target coverage was respected with the adaptive treatment: 97.3% for the bladder Clinical Target Volume (CTV) (99.5; [60.1-100]) and 98% for the bladder+lymph nodes CTV (98.6; [85.4-100]). Concerning OAR, the volume of healthy tissue spared was 43.7% on average and the V45Gy for the small bowel was 43,4cc (35; [0-129]) (versus 57,6cc). The rectal D50 was on average 18,7Gy for the adaptive treatment (15.9; [2.4-44.1]) versus 17Gy with the conventional approach. With a median follow-up of 2.94 years (95% CI: [0.92-4.02]), we observed three grade 3 toxicities (30%). No grade 4 toxicity was observed. The 2-year overall survival and progression-free survival rates were 65.6% (95% CI: [26-87.6]) and 45.7% (95% CI: [14.3-73]), respectively.

CONCLUSION

The ART technique using a PoD strategy showed a reduction of the irradiated healthy tissue volume while maintaining a similar bladder coverage, with an acceptable rate of toxicity.

Synthesis of Illudinine from Dimedone and Identification of Activity as a Monoamine Oxidase Inhibitor

The fungal metabolite illudinine is prepared in seven steps and ca. 55% overall yield from dimedone using an "open and shut" (ring-opening and ring-closing) strategy. Tandem ring-opening fragmentation and olefination of dimedone establishes alkyne and vinylarene functionality linked by a neopentylene tether. Oxidative cycloisomerization then provides the illudinine framework. The key innovation in this second-generation synthesis of illudinine is the use of the nitrile functional group, rather than an ester, as the functional precursor to the carboxylic acid of illudinine. The small, linear nitrile (C≡N) is associated with improved selectivity, π-conjugation, and reactivity at multiple points in the synthetic sequence relative to the carboxylic acid ester. Preliminary assays indicate that illudinine and several related synthetic analogues are monoamine oxidase inhibitors, which is the first reported indication of biological activity associated with this natural product. Illudinine was found to inhibit monoamine oxidase B (MAO-B) with an IC₅₀ of 18 ± 7.1 μM in preliminary assays.

Inflammation in areas of fibrosis: The DeKAF prospective cohort

Inflammation in areas of fibrosis (i-IFTA) in posttransplant biopsy specimens has been associated with decreased death-censored graft survival (DC-GS). Additionally, an i-IFTA score ≥ 2 is part of the diagnostic criteria for chronic active TCMR (CA TCMR). We examined the impact of i-IFTA and t-IFTA (tubulitis in areas of atrophy) in the first biopsy for cause after 90 days posttransplant (n = 598); mean (SD) 1.7 ± 1.4 years posttransplant. I-IFTA, present in 196 biopsy specimens, was strongly correlated with t-IFTA, and Banff i. Of the 196, 37 (18.9%) had a previous acute rejection episode; 96 (49%) had concurrent i score = 0. Unlike previous studies, i-IFTA = 1 (vs 0) was associated with worse 3-year DC-GS: (i-IFTA = 0, 81.7%, [95% CI 77.7 to 85.9%]); i-IFTA = 1, 68.1%, [95% CI 59.7 to 77.6%]; i-IFTA = 2, 56.1%, [95% CI 43.2 to 72.8%], i-IFTA = 3, 48.5%, [95% CI 31.8 to 74.0%]). The association of i-IFTA with decreased DC-GS remained significant when adjusted for serum creatinine at the time of the biopsy, Banff i, ci and ct, C4d and DSA. T-IFTA was similarly associated with decreased DC-GS. Of these indication biopsies, those with i-IFTA ≥ 2, without meeting other criteria for CA TCMR had similar postbiopsy DC-GS as those with CA TCMR. Those with i-IFTA = 1 and t ≥ 2, ti ≥ 2 had postbiopsy DC-GS similar to CA TCMR. Biopsies with i-IFTA = 1 had similar survival as CA TCMR when biopsy specimens also met Banff criteria for TCMR and/or AMR. Studies of i-IFTA and t-IFTA in additional cohorts, integrating analyses of Banff scores meeting criteria for other Banff diagnoses, are needed.

Long-term follow-up of the DeKAF cross-sectional cohort study

The DeKAF study was developed to better understand the causes of late allograft loss. Preliminary findings from the DeKAF cross-sectional cohort (with follow-up < 20 months) have been published. Herein, we present long-term outcomes in those recipients (mean follow-up ± SD, 6.6 ± 0.7 years). Eligibility included being transplanted prior to October 1, 2005; serum creatinine ≤ 2.0 mg/dL on January 1, 2006; and subsequently developing new-onset graft dysfunction leading to a biopsy. Mean time from transplant to biopsy was 7.5 ± 6.1 years. Histologic findings and DSA were studied in relation to postbiopsy outcomes. Long-term follow-up confirms and expands the preliminary results of each of 3 studies: (1) increasing inflammation in area of atrophy (irrespective of inflammation in nonscarred areas [Banff i]) was associated with increasingly worse postbiopsy death-censored graft survival; (2) hierarchical analysis based on Banff scores defined clusters (entities) that differed in long-term death-censored graft survival; and (3) C4d-/DSA- recipients had significantly better (and C4d+/DSA+ worse) death-censored graft survival than other groups. C4d+/DSA- and C4d-/DSA+ had similar intermediate death-censored graft survival. Clinical and histologic findings at the time of new-onset graft dysfunction define high- vs low-risk groups for long-term death-censored graft survival, even years posttransplant. These findings can help differentiate groups for potential intervention studies.

Allograft and patient survival after sequential HSCT and kidney transplantation from the same donor-A multicenter analysis

Tolerance induction through simultaneous hematopoietic stem cell and renal transplantation has shown promising results, but it is hampered by the toxicity of preconditioning therapies and graft-versus-host disease (GVHD). Moreover, renal function has never been compared to conventionally transplanted patients, thus, whether donor-specific tolerance results in improved outcomes remains unanswered. We collected follow-up data of published cases of renal transplantations after hematopoietic stem cell transplantation from the same donor and compared patient and transplant kidney survival as well as function with caliper-matched living-donor renal transplantations from the Austrian dialysis and transplant registry. Overall, 22 tolerant and 20 control patients were included (median observation period 10 years [range 11 months to 26 years]). In the tolerant group, no renal allograft loss was reported, whereas 3 were lost in the control group. Median creatinine levels were 85 μmol/l (interquartile range [IQR] 72-99) in the tolerant cohort and 118 μmol/l (IQR 99-143) in the control group. Mixed linear-model showed around 29% lower average creatinine levels throughout follow-up in the tolerant group (P < .01). Our data clearly show stable renal graft function without long-term immunosuppression for many years, suggesting permanent donor-specific tolerance. Thus sequential transplantation might be an alternative approach for future studies targeting tolerance induction in renal allograft recipients.

Apolipoprotein L1 and Chronic Kidney Disease Risk in Young Potential Living Kidney Donors

OBJECTIVE

The aim of this study was to develop a novel chronic kidney disease (CKD) risk prediction tool for young potential living kidney donors.

SUMMARY OF BACKGROUND DATA

Living kidney donor selection practices have evolved from examining individual risk factors to a risk calculator incorporating multiple characteristics. Owing to limited long-term data and lack of genetic information, current risk tools lack precision among young potential living kidney donors, particularly African Americans (AAs).

METHODS

We identified a cohort of young adults (18-30 years) with no absolute contraindication to kidney donation from the longitudinal cohort study Coronary Artery Risk Development in Young Adults. Risk associations for CKD (estimated glomerular filtration rate <60 mL/min/1.73 m) were identified and assigned weighted points to calculate risk scores.

RESULTS

A total of 3438 healthy adults were identified [mean age 24.8 years; 48.3% AA; median follow-up 24.9 years (interquartile range: 24.5-25.2)]. For 18-year olds, 25-year projected CKD risk varied by ethnicity and sex even without baseline clinical and genetic abnormalities; risk was 0.30% for European American (EA) women, 0.52% for EA men, 0.52% for AA women, 0.90% for AA men. Among 18-year-old AAs with apolipoprotein L1 gene (APOL1) renal-risk variants without baseline abnormalities, 25-year risk significantly increased: 1.46% for women and 2.53% for men; among those with 2 APOL1 renal-risk variants and baseline abnormalities, 25-year risk was higher: 2.53% to 6.23% for women and 4.35% to 10.58% for men.

CONCLUSIONS

Young AAs were at highest risk for CKD, and APOL1 renal-risk variants drove some of this risk. Understanding the genetic profile of young AA potential living kidney donors in the context of baseline health characteristics may help to inform candidate selection and counseling.

Xenotransplantation-the current status and prospects

Introduction

There is a continuing worldwide shortage of organs from deceased human donors for transplantation into patients with end-stage organ failure. Genetically engineered pigs could resolve this problem, and could also provide tissues and cells for the treatment of conditions such as diabetes, Parkinson's disease and corneal blindness.

Sources of data

The current literature has been reviewed.

Areas of agreement

The pathobiologic barriers are now largely defined. Research progress has advanced through the increasing availability of genetically engineered pigs and novel immunosuppressive agents. Life-supporting pig kidneys and islets have functioned for months or years in nonhuman primates.

Areas of controversy

The potential risk of transfer of a pig infectious microorganism to the recipient continues to be debated.

Growing points

Increased attention is being paid to selection of patients for initial clinical trials.

Areas timely for developing research

Most of the advances required to justify a clinical trial have now been met.

Evaluating and Extending the Ocean Wind Climate Data Record

Satellite microwave sensors, both active scatterometers and passive radiometers, have been systematically measuring near-surface ocean winds for nearly 40 years, establishing an important legacy in studying and monitoring weather and climate variability. As an aid to such activities, the various wind datasets are being intercalibrated and merged into consistent climate data records (CDRs). The ocean wind CDRs (OW-CDRs) are evaluated by comparisons with ocean buoys and intercomparisons among the different satellite sensors and among the different data providers. Extending the OW-CDR into the future requires exploiting all available datasets, such as OSCAT-2 scheduled to launch in July 2016. Three planned methods of calibrating the OSCAT-2 σ_o measurements include 1) direct Ku-band σ_o intercalibration to QuikSCAT and RapidScat; 2) multisensor wind speed intercalibration; and 3) calibration to stable rainforest targets. Unfortunately, RapidScat failed in August 2016 and cannot be used to directly calibrate OSCAT-2. A particular future continuity concern is the absence of scheduled new or continuation radiometer missions capable of measuring wind speed. Specialized model assimilations provide 30-year long high temporal/spatial resolution wind vector grids that composite the satellite wind information from OW-CDRs of multiple satellites viewing the Earth at different local times.

Access to Kidney Transplantation among HIV-Infected Waitlist Candidates

BACKGROUND AND OBJECTIVES

Kidney transplantation among HIV-infected patients with ESRD confers a significant survival benefit over remaining on dialysis. Given the high mortality burden associated with dialysis, understanding access to kidney transplantation after waitlisting among HIV+ candidates is warranted.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the Scientific Registry of Transplant Recipients were linked to Intercontinental Marketing Statistics pharmacy fills (January 1, 2001 to October 1, 2012) so that we could identify and study 1636 HIV+ (defined as having filled one or more antiretroviral medications unique to HIV treatment) and 72,297 HIV- kidney transplantation candidates.

RESULTS

HIV+ waiting list candidates were more often young (<50 years old: 62.7% versus 37.6%; P<0.001), were more often men (75.2% versus 59.3%; P<0.001), were more often black (73.6% versus 27.9%; P<0.001), had longer time on dialysis (years: 2.5 versus 0.8; P<0.001), were more often coinfected with hepatitis C virus (9.0% versus 3.9%; P<0.001), and were less likely to remain active on the waiting list (37.7% versus 49.4%; P<0.001). Waitlist mortality among HIV+ candidates was similar compared with HIV- candidates (adjusted hazard ratio, 1.03; 95% confidence interval, 0.89 to 1.20; P=0.67). In contrast, likelihood of living donor kidney transplantation was 47% lower (adjusted hazard ratio, 0.53; 95% confidence interval, 0.44 to 0.64; P<0.001), and there was a trend toward lower likelihood of deceased donor kidney transplantation (adjusted hazard ratio, 0.87; 95% confidence interval, 0.74 to 1.01; P=0.07) compared with in HIV- candidates.

CONCLUSIONS

Our findings highlight the need for additional study to better understand disparities in access to kidney transplantation, particularly living donor kidney transplantation, among HIV+ kidney waitlist candidates.

Obesity increases the risk of end-stage renal disease among living kidney donors

Determining candidacy for live kidney donation among obese individuals remains challenging. Among healthy non-donors, body mass index (BMI) above 30 is associated with a 16% increase in risk of end-stage renal disease (ESRD). However, the impact on the ESRD risk attributable to donation and living with only one kidney remains unknown. Here we studied the risk of ESRD associated with obesity at the time of donation among 119 769 live kidney donors in the United States. Maximum follow-up was 20 years. Obese (BMI above 30) live kidney donors were more likely male, African American, and had higher blood pressure. Estimated risk of ESRD 20 years after donation was 93.9 per 10 000 for obese; significantly greater than the 39.7 per 10 000 for non-obese live kidney donors. Adjusted for age, sex, ethnicity, blood pressure, baseline estimated glomerular filtration rate, and relationship to recipient, obese live kidney donors had a significant 86% increased risk of ESRD compared to their non-obese counterparts (adjusted hazard ratio 1.86; 95% confidence interval 1.05-3.30). For each unit increase in BMI above 27 kg/m² there was an associated significant 7% increase in ESRD risk (1.07, 1.02-1.12). The impact of obesity on ESRD risk was similar for male and female donors, African American and Caucasian donors, and across the baseline estimated glomerular filtration rate spectrum. These findings may help to inform selection criteria and discussions with persons considering living kidney donation.

Identification of strategies to facilitate organ donation among African Americans using the nominal group technique

BACKGROUND AND OBJECTIVES

African Americans are disproportionately affected by ESRD, but few receive a living donor kidney transplant. Surveys assessing attitudes toward donation have shown that African Americans are less likely to express a willingness to donate their own organs. Studies aimed at understanding factors that may facilitate the willingness of African Americans to become organ donors are needed.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A novel formative research method was used (the nominal group technique) to identify and prioritize strategies for facilitating increases in organ donation among church-attending African Americans. Four nominal group technique panel interviews were convened (three community and one clergy). Each community panel represented a distinct local church; the clergy panel represented five distinct faith-based denominations. Before nominal group technique interviews, participants completed a questionnaire that assessed willingness to become a donor; 28 African-American adults (≥19 years old) participated in the study.

RESULTS

In total, 66.7% of participants identified knowledge- or education-related strategies as most important strategies in facilitating willingness to become an organ donor, a view that was even more pronounced among clergy. Three of four nominal group technique panels rated a knowledge-based strategy as the most important and included strategies, such as information on donor involvement and donation-related risks; 29.6% of participants indicated that they disagreed with deceased donation, and 37% of participants disagreed with living donation. Community participants' reservations about becoming an organ donor were similar for living (38.1%) and deceased (33.4%) donation; in contrast, clergy participants were more likely to express reservations about living donation (33.3% versus 16.7%).

CONCLUSIONS

These data indicate a greater opposition to living donation compared with donation after one's death among African Americans and suggest that improving knowledge about organ donation, particularly with regard to donor involvement and donation-related risks, may facilitate increases in organ donation. Existing educational campaigns may fall short of meeting information needs of African Americans.

The APOL1 genotype of African American kidney transplant recipients does not impact 5-year allograft survival

Apolipoprotein L-1 (APOL1) gene variants are associated with end-stage renal disease in African Americans (AAs). Here we investigate the impact of recipient APOL1 gene distributions on kidney allograft outcomes. We conducted a retrospective analysis of 119 AA kidney transplant recipients, and found that 58 (48.7%) carried two APOL1 kidney disease risk variants. Contrary to the association seen in native kidney disease, there is no difference in allograft survival at 5-year posttransplant for recipients with high-risk APOL1 genotypes. Thus, we were able to conclude that APOL1 genotypes do not increase risk of allograft loss after kidney transplantations, and carrying 2 APOL1 risk alleles should not be an impediment to transplantation.

The PROMISE study: a phase 2b multicenter study of voclosporin (ISA247) versus tacrolimus in de novo kidney transplantation

Voclosporin (VCS, ISA247) is a novel calcineurin inhibitor being developed for organ transplantation. PROMISE was a 6-month, multicenter, randomized, open-label study of three ascending concentration-controlled groups of VCS (low, medium and high) compared to tacrolimus (TAC) in 334 low-risk renal transplant recipients. The primary endpoint was demonstration of noninferiority of biopsy proven acute rejection (BPAR) rates. Secondary objectives included renal function, new onset diabetes after transplantation (NODAT), hypertension, hyperlipidemia and pharmacokinetic-pharmacodynamic evaluation. The incidence of BPAR in the VCS groups (10.7%, 9.1% and 2.3%, respectively) was noninferior to TAC (5.8%). The incidence of NODAT for VCS was 1.6%, 5.7% and 17.7% versus 16.4% in TAC (low-dose VCS, p = 0.03). Nankivell estimated glomerular filtration rate was respectively: 71, 72, 68 and 69 mL/min, statistically lower in the high-dose group, p = 0.049. The incidence of hypertension and adverse events was not different between the VCS groups and TAC. VCS demonstrated an excellent correlation between trough and area under the curve (r(2) = 0.97) and no difference in mycophenolic acid exposure compared to TAC. This 6-month study shows VCS to be as efficacious as TAC in preventing acute rejection with similar renal function in the low- and medium-exposure groups, and potentially associated with a reduced incidence of NODAT.

Living kidney donor follow-up: state-of-the-art and future directions, conference summary and recommendations

In light of continued uncertainty regarding postkidney donation medical, psychosocial and socioeconomic outcomes for traditional living donors and especially for donors meeting more relaxed acceptance criteria, a meeting was held in September 2010 to (1) review limitations of existing data on outcomes of living kidney donors; (2) assess and define the need for long-term follow-up of living kidney donors; (3) identify the potential system requirements, infrastructure and costs of long-term follow-up for living kidney donor outcomes in the United States and (4) explore practical options for future development and funding of United States living kidney donor data collection, metrics and endpoints. Conference participants included prior kidney donors, physicians, surgeons, medical ethicists, social scientists, donor coordinators, social workers, independent donor advocates and representatives of payer organizations and the federal government. The findings and recommendations generated at this meeting are presented.

Pathological and clinical characterization of the 'troubled transplant': data from the DeKAF study

We are studying two cohorts of kidney transplant recipients, with the goal of defining specific clinicopathologic entities that cause late graft dysfunction: (1) prevalent patients with new onset late graft dysfunction (cross-sectional cohort); and (2) newly transplanted patients (prospective cohort). For the cross-sectional cohort (n = 440), mean time from transplant to biopsy was 7.5 +/- 6.1 years. Local pathology diagnoses included CAN (48%), CNI toxicity (30%), and perhaps surprisingly, acute rejection (cellular- or Ab-mediated) (23%). Actuarial rate of death-censored graft loss at 1 year postbiopsy was 17.7%; at 2 years, 29.8%. There was no difference in postbiopsy graft survival for recipients with versus without CAN (p = 0.9). Prospective cohort patients (n = 2427) developing graft dysfunction >3 months posttransplant undergo 'index' biopsy. The rate of index biopsy was 8.8% between 3 and 12 months, and 18.2% by 2 years. Mean time from transplant to index biopsy was 1.0 +/- 0.6 years. Local pathology diagnoses included CAN (27%), and acute rejection (39%). Intervention to halt late graft deterioration cannot be developed in the absence of meaningful diagnostic entities. We found CAN in late posttransplant biopsies to be of no prognostic value. The DeKAF study will provide broadly applicable diagnostic information to serve as the basis for future trials.

Histopathologic clusters differentiate subgroups within the nonspecific diagnoses of CAN or CR: preliminary data from the DeKAF study

The nonspecific diagnoses 'chronic rejection''CAN', or 'IF/TA' suggest neither identifiable pathophysiologic mechanisms nor possible treatments. As a first step to developing a more useful taxonomy for causes of new-onset late kidney allograft dysfunction, we used cluster analysis of individual Banff score components to define subgroups. In this multicenter study, eligibility included being transplanted prior to October 1, 2005, having a 'baseline' serum creatinine < or =2.0 mg/dL before January 1, 2006, and subsequently developing deterioration of graft function leading to a biopsy. Mean time from transplant to biopsy was 7.5 +/- 6.1 years. Of the 265 biopsies (all with blinded central pathology interpretation), 240 grouped into six large (n > 13) clusters. There were no major differences between clusters in recipient demographics. The actuarial postbiopsy graft survival varied by cluster (p = 0.002). CAN and CNI toxicity were common diagnoses in each cluster (and did not differentiate clusters). Similarly, C4d and presence of donor specific antibody were frequently observed across clusters. We conclude that for recipients with new-onset late graft dysfunction, cluster analysis of Banff scores distinguishes meaningful subgroups with differing outcomes.

Phase 1 dose-escalation study of CP-690 550 in stable renal allograft recipients: preliminary findings of safety, tolerability, effects on lymphocyte subsets and pharmacokinetics

CP-690 550 inhibits Janus kinase 3 with nanomolar potency. In this dose-escalation study, we assessed the safety, tolerability, effects on lymphocyte subsets, and pharmacokinetics of CP-690 550 when coadministered with mycophenolate mofetil in stable renal allograft recipients for 28 days. Twenty-eight patients were enrolled. Six patients received CP-690 550 5 mg twice daily (BID), 6 patients received 15 mg BID, 10 patients received 30 mg BID, and 6 patients received placebo. The most frequent adverse events were infections and gastrointestinal (abdominal pain, diarrhea, dyspepsia, and vomiting). CP-690 550 15 mg BID and 30 mg BID were associated with a mean decrease in hemoglobin from baseline of 11% and a mean decrease in absolute natural killer cell counts of 50%. CP-690 550 30 mg BID was also associated with a mean increase in absolute CD19(+) B-lymphocytes of 130%. There were no changes in the number of neutrophils, total lymphocytes, platelets, or CD4(+) or CD8(+) T cells; clinical chemistry; vital signs; or electrocardiograms from the pretreatment baseline. Administration of CP-690 550 without a concomitant calcineurin inhibitor resulted in CP-690 550 exposures consistent with previous studies in nontransplant subjects. Additional dose-ranging studies are warranted to evaluate the safety and efficacy of CP-690 550 in renal transplant recipients over longer treatment duration.

Role of beta3 integrin in acute renal allograft rejection in humans

BACKGROUND AND OBJECTIVES

Beta3 Integrin may play a role in the process of acute rejection by increasing leukocyte adhesion to the endothelium, cytotoxic T lymphocyte activation, and platelet aggregation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

For investigation of the role of beta3 integrin in the pathogenesis of acute rejection, this study examined the surface expression of beta3 integrin on leukocyte subsets and analyzed a common single-nucleotide polymorphism in exon 2 of the gene encoding the beta3 subunit that generates two beta3 integrin isoforms, termed Pl(A1) and Pl(A2). Pl(A) genotype was determined in blood samples from 445 renal allograft recipients at two centers. Patients were then grouped by Pl(A) genotype, and clinical outcomes as recorded in a preexisting database were analyzed.

RESULTS

Although almost all monocytes express beta3 integrin, its expression was also found on all leukocyte subsets, including T, B, and NK cells. The percentage of patients who experienced acute rejection was noted to be significantly higher in those with Pl(A1)/Pl(A1) (TT) genotype versus patients with the Pl(A1)/Pl(A2) or Pl(A2)/Pl(A2) (CT or CC) genotypes (33% for TT versus 20% for CT or CC). In a multivariate analysis, the Pl(A1)/Pl(A1) (TT) genotype remained significantly associated with acute rejection. Patients with Pl(A1)/Pl(A1) (TT) genotype also exhibited a higher number of acute rejection episodes per patient.

CONCLUSIONS

The Pl(A1)/Pl(A1) (TT) genotype is associated with an increased incidence of acute renal allograft rejection in humans, supporting a role for beta3 integrin in the pathophysiology of acute rejection.

Positive margins in laparoscopic partial nephrectomy in 855 cases: a multi-institutional survey from the United States and Europe

PURPOSE

Open partial nephrectomy has emerged as the standard of care in the management of renal tumors smaller than 4 cm. While laparoscopic radical nephrectomy has been shown to be comparable to open radical nephrectomy with respect to long-term outcomes, important questions remain unanswered regarding the oncological efficacy of laparoscopic partial nephrectomy. We examined the practice patterns and pathological outcomes following laparoscopic partial nephrectomy.

MATERIALS AND METHODS

A survey was sent to academic medical centers in the United States and in Europe performing laparoscopic partial nephrectomy. The total number of laparoscopic partial nephrectomies, positive margins, indications for intraoperative frozen biopsy as well as tumor size and position were queried.

RESULTS

Surveys suitable for analysis were received from 17 centers with a total of 855 laparoscopic partial nephrectomy cases. Mean tumor size was 2.7 cm (+/-0.6). There were 21 cases with positive margins on final pathology, giving an overall positive margin rate of 2.4%. Intraoperative frozen sections were performed selectively at 10 centers based on clinical suspicion of positive margins on excised tumor. Random biopsies were routinely performed on the resection bed at 5 centers. Frozen sections were never performed at 2 centers. Of the 21 cases with positive margins 14 underwent immediate radical nephrectomy based on the frozen section and 7 were followed expectantly.

CONCLUSIONS

Early experience with laparoscopic partial nephrectomy in this multicenter study demonstrates oncological efficacy comparable to that of open partial nephrectomy with respect to the incidence of positive margins. The practice of intraoperative frozen sections varied among centers and is not definitive in guiding the optimal surgical treatment.

Dietary essential fatty acids and gender-specific behavioral responses in cranially irradiated rats

Specific memory deficits, reduced intellectual processing speed, and a variety of social and behavioral problems have been implicated as long-term effects of cranial radiation therapy (CRT). These deficits are thought to be related to changes in brain cytology and structure associated with microvascular aberrations. N-3 fatty acids may serve as protectants in pediatric patients who receive CRT for brain tumors. Timed-pregnant rat dams were fed one of four diets that were identical in all respects, except for their essential fatty acid content. The dams were placed on these diets at the beginning of the third trimester of gestation and their pups remained on them throughout the study. The rats' behavioral response as judged by acoustic startle response (ASR) and neurocognitive response (performance in a radial maze, RM) were evaluated in relation to diet, gender, and CRT. The following hypotheses were tested: (1) female rats will show greater CRT-induced neurocognitive and behavioral deficits; (2) dietary n-3 fatty acids will diminish CRT-induced neurocognitive and behavioral deficits; (3) gender-specific differences would be dampened by n-3 fatty acids in the diet. All three hypotheses were partially supported. These findings are discussed in light of the potential neuroprotective effects of n-3 fatty acids.

Nerve Sparing Laparoscopic Radical Prostatectomy: Our Technique

PURPOSE

To describe our technique of nerve sparing laparoscopic radical prostatectomy (LRP). We present the oncological and functional results (potency and urinary continence).

MATERIAL AND METHODS

LRP has become standard at our institution based on experience with more than 2800 consecutive cases operated on between 1997 and 2005. From May 2003 to March 2005 a total of 677 LRP were performed, 425 consecutive patients candidates for a nerve sparing technique have been operated using the intrafascial approach. The challenge of our technique is to remove the prostate without any thermic and mechanic traumatism, avoiding dissection of outer layer. Oncological data were assessed by pathological examination and post-operative PSA level. Functional results were assessed with a self questionnaire.

RESULTS

By pathological stage, 2 pT2a specimens (7.4%), 7 pT2b specimens (21%), 44 pT2c specimens (24%), 63 pT3a specimens (43%), 11 pT3b specimens (46%) were found to have positive surgical margins (SMs). In 86 specimen (59%) positive SMs were focal inframillimetric. Median follow-up was 11 months (range 1-22). The continence rate (no leakage/no pad) was 95% at 6 months, confirmed at 12 months among 202 patients. For 137 patients, potency rate was 58.5% at 12 months.

CONCLUSION

Intrafascial LRP provides satisfactory results in regard to recovery of continence and sexual function. Long-term progression and survival outcome are necessary before this procedure should be offered as a replacement for interfascial nerve sparing technique.

[Laparoscopic promontofixation technique]

Laparoscopic promontofixation often remains possible whatever the previous history of pelvic surgery, including the placing of prosthetic material. Preoperative care is standardized and is accompanied by antibiotic prophylaxis, preventive antithrombotic treatment and in the event of a history of pelvic surgery, a digestive preparation. Positioning of the patient must plan a 30 degrees Trendelenbourg position. After the introduction of trocars, initial surgery comprises interrectovaginal dissection to free the whole posterior surface of the vagina. This is followed by the installation of a posterior mesh pre-cut in an arch. The anterior face of the promontory is then freed after incision of the posterior peritoneum with the patient placed beforehand in a Trendelenbourg position. After intervesical vaginal dissection, the anterior prosthesis comprising a precut polyester mesh is fixed avoiding excess traction. The end of the surgery involves careful reperitonization of all the prosthetic parts. Possible specific surgical complications are vascular and visceral wounds. Postoperative secondary haemorrhage and gastrointestinal occlusion may occur. Occurrence of an inflammatory syndrome and low back pain suggests spondylodicitis and MRI should be performed. Vaginal erosion on the prosthesis (1.6 to 10% depending on the series) may occur after several months and seems relatively independent of the prosthetic material used.

Subcutaneous interleukin-2, interferon alpha-2b and 5-fluorouracil in metastatic renal cell carcinoma as second-line treatment after failure of previous immunotherapy: a phase II trial

The association of interleukin-2 (IL-2), interferon alpha-2a (IFNalpha), 5-fluorouracil (5-FU) has been reported to induce response in metastatic renal cell carcinoma (MRCC). This study evaluated IL-2, IFNalpha and 5FU as second-line treatment after failure under immunotherapy. A total of 35 patients received IL-2, at 9 x 10(6) IU m(-2), once or t.i.d, 5 days a week, every other week. Interferon alpha was administered at 6 MUI, TIW along with IL-2 every week. 5-Fluorouracil was given at 750 mg m(-2) day(-1) on days 1-5 every 4 weeks. One cycle lasted 8 weeks. All patients were evaluable for response and toxicity. There were two objective responses (5.7%) and 14 stable diseases (40%). Survival was 14 months. In all, 17 patients experienced grade 3 toxicity. The predictive factor for progression to second-line immunotherapy was the results of first-line immunotherapy, and performance status, delay from primary tumour to metastases and response or stabilisation to chemo-immunotherapy for survival. IL-2, IFNalpha and 5-FU induce low objective response but stabilisation in patients with MRCC having failed with immunotherapy, and may be considered only in selected patients on performance status, stabilisation or response after first-line immunotherapy and interval from their primary tumour to metastases.

Equivalent pharmacokinetics of mycophenolate mofetil in African-American and Caucasian male and female stable renal allograft recipients

African-American (AA) renal transplant recipients require higher doses of mycophenolate mofetil (MMF) than Caucasians. A hypothesized pharmacokinetic (PK) difference was tested in stable renal transplant recipients. Whole blood was collected before, and 20, 40 and 75 min, and 2, 3, 4, 6, 8 and 12 h after the MMF dose. Mycophenolic acid (MPA) and its glucuronide metabolite (MPAG) were analyzed using HPLC. Analysis of variance was performed for the primary end-points of dose-adjusted PK parameters AUC0-12 and Cmax of MPA using log-transformed values. Differences between races and genders were estimated: 90% confidence intervals (CI) were calculated. Back-transformation gave estimates of the race and gender ratio and their CI. Equivalence of the groups was determined if the 90% confidence limits were included in the interval (0.80, 1.25). The calculated PK parameters were comparable among the four subgroups (Caucasian, AA, Male, Female). The 90% CIs for the ratio of dose-adjusted AUC0-12 of MPA between races were between 89.7 and 112.9%. There were no race, gender or race-by-gender effects (p-values = 0.196) nor differences between diabetics and nondiabetics. This study demonstrates that dosing requirement for MMF in AA and Caucasians is unlikely to be related to different exposures to MPA.

Evolution of immunosuppression and continued importance of acute rejection in renal transplantation

As steady improvement in short-term kidney graft survival and long-term outcomes prolongs the lives of transplant patients, responsibility for their care is shifting away from transplant specialists and into the hands of community nephrologists. Therefore, community nephrologists need to have a deeper understanding of immunosuppressive therapies than ever before. Pharmacologic immunosuppression has been continuously evolving over the past two decades. Azathioprine was introduced in the early 1960s. Introduction of cyclosporine (CsA) in 1983 revolutionized short-term outcomes after renal transplantation. The first monoclonal antibody immunosuppressant, OKT3, was introduced in 1986. The 1990s saw the introduction of a number of important new agents, including mycophenolate mofetil (MMF), tacrolimus, and a microemulsion CsA, as well as two new monoclonal antibodies. Combinations of these new agents, along with improving clinical care, have produced 1-year patient survival approaching 100% and graft survival exceeding 90%. The newest class of agents, the first of which is sirolimus, is called target of rapamycin (TOR) inhibitors and is used with CsA for maintenance therapy. Immunosuppressive drug therapy after kidney transplantation continues to evolve. There is a variety of pharmacologic combinations from which to choose, based on immunologic risk and side effect profiles. As new regimens are developed, ongoing communications between the transplant center and community nephrologists will be required to implement therapeutic changes and optimize patient care successfully.

Proposal for a "European Scoring System for Laparoscopic Operations in Urology"

PURPOSE

To propose a scoring system of difficulties for the most currently performed laparoscopic procedures in urology.

MATERIALS AND METHODS

Each current laparoscopic procedure has been evaluated according to three different criteria: technical difficulty, operative risk and the attention required. Each criterion is scored from 1 (minimal impact of the criteria) to 7 (maximal impact of the criteria). The sum of the 3 criteria is used to classify each operation according to an increasing level of global difficulty, classified into 6 levels: easy (E: sum of criteria between 3 and 5), slightly difficult (SD: sum of criteria between 6 and 8), fairly difficult (FD: sum of criteria between 9 and 11), difficult (D: sum of criteria between 12 and 14), very difficult (VD: sum of criteria between 15 and 17), extremely difficult (ED: sum of criteria greater than 18).

RESULTS

Procedures currently performed by laparoscopy have been selected for evaluation according to the above criteria, and retrospectively validated by European experts in laparoscopic urology according to their experience and the international literature.

CONCLUSION

This proposal of a scoring scale system is a basis for discussion, teaching and learning of urological laparoscopy. By necessity, this scale is evolving and will be regularly reconsidered and updated every 5 years.

In vitro immunization of patient T cells with autologous bone marrow antigen presenting cells pulsed with tumor lysates

Presentation of cell-associated antigen to T cells is a critical event in the initiation of an anti-tumor immune response but it appears to often be deficient or limiting. Here we report an experimental system for stimulation of human T lymphocytes using autologous antigen presenting cells (APCs) and autologous tumor cells. Two types of APCs were prepared from human bone marrow: MC and DC. MC were produced by using GM-CSF and SCF. DC were obtained with the same cytokines plus IL-4. DC and MC were generated in parallel from the same patients and their phenotypes and capacities to prime T lymphocytes were analyzed and compared. MC were CD14+, CD1a-, CD33+ and HLA-DR+. Two populations of DC were defined: immature DC were uniformly CD1a-; mature DC expressed CD1a, CD80, CD86, HLA-DR, CD54 and CD58 but lacked surface CD14. Stimulation of autologous T lymphocytes was studied by measuring their proliferation and cytotoxic function. In more than 80% of our experiments the proliferation of autologous T lymphocytes cocultured with APC pulsed or not with tumor cell lysates was higher than that of T cells cultured alone. DC were more effective than MC in stimulating proliferation of lymphocytes. The capacity of a patient's autologous bone marrow-derived APC to stimulate T cells when exposed to autologous tumor cell lysates suggest that such antigen-exposed APC may be useful in specific anti-tumor immunotherapy protocols.