Influence of dialysis duration and modality on kidney transplant outcomes

BACKGROUND

The influence of pretransplantation dialysis on kidney transplant outcomes has been the subject of longstanding interest. Although increased time on dialysis prior to kidney transplantation is associated with decreased graft and patient survivals, analyses of the impact of dialysis modality on kidney allograft outcome have produced conflicting results.

OBJECTIVE

The objective of this study was to evaluate the influence of dialysis duration and modality on the function and survival of renal allografts.

PATIENTS

We retrospectively reviewed the clinical data of 421 adults who received first kidney transplantations from cadaveric heart-beating donors performed in our unit from May 1989 to May 2007. Three hundred seventy-four patients (88.8%) were on hemodialysis (HD) prior to kidney transplantation, including 247 patients (58.7%) on treatment for at least 24 months.

RESULTS

Patients with a dialysis duration > or =24 months were significantly older (45.9 vs 42.8 years; P = .013). Renal function at 3, 12, 60, and 96 months was similar between the 2 groups. Longer duration on dialysis was associated with poorer overall graft and patient survivals. No differences were observed in renal function or graft and patient survivals comparing HD or peritoneal dialysis (PD). Multivariate analysis confirmed the lack of correlation between dialysis duration or modality and allograft failure.

CONCLUSION

Longer dialysis duration influenced overall graft and patient survival. However, dialysis modality showed no influence on graft function or survival.

Impact of donor age on renal allograft function and survival

BACKGROUND

The lack of cadaveric donors coupled with a rapidly growing number of potential recipients have stimulated the implementation of several strategies, including the acceptance of older donors, to increase the organ pool and reduce the waiting list for kidney transplantation. However several studies have demonstrated higher incidences of delayed graft function and poor graft outcomes among kidneys harvested from older donors.

OBJECTIVE

The objective of this study was to evaluate the influence of donor age on the function and long-term survival of renal allografts.

PATIENTS

We performed a retrospective review of the clinical data from 441 adult kidney transplantation from cadaveric heart-beating donors performed in our unit from May 1989 to May 2007.

RESULTS

Recipients of kidney allografts from older donors were significantly older (49.2 vs 43.7 years; P < .0001) and had a higher incidence of delayed graft function (15.1% vs 5.4%; P = .005). Renal function was superior following kidney transplantation using younger donors not only at 3 months (P < .0001) and 12 months (P < .0001) posttransplantation, but also upon long-term follow-up at 60 months (P < .0001) and 96 months (P = .030). Allograft survival censored for death with a functioning graft and patient survival were not different when comparing older versus younger donors. Multivariate analysis confirmed the lack of correlation between donor age and allograft failure.

CONCLUSION

Donor age showed no influence on allograft survival. However, kidney allografts from older donors displayed lower first year and long-term renal function.

Induction immunosuppressive therapy in renal transplantation: does basiliximab make the difference?

The optimal prophylactic induction immunosuppressive therapy to prevent renal transplant rejection remains controversial. Recently, basiliximab efficiency has been reported in several studies. We sought to evaluate the efficiency of induction immunosuppressive therapy with basiliximab in renal transplantation in our unit based upon the acute rejection rate, patient and graft survivals, first hospital admission length, and incidence of infectious or malignant complications during 4 years of follow-up. We retrospectively evaluated the outcome of two groups of renal transplant recipients treated with triple immunosuppressive therapy (cyclosporine, mycophenolate mofetil, and prednisolone) without (group 1, 149 patients) or with (group 2, 104 patients) induction immunosuppression with basiliximab. The two groups did not differ in demographic characteristics, number of hypersensitized patients, cold ischemia time, or donor age. The group receiving basiliximab displayed a significantly lower acute rejection rate (7.6% vs 24%, P = .001) and shorter first hospital admission (14.4 +/- 8 vs 19.5 +/- 11 days). There was no difference in graft or patient survival, death due to sepsis, or incidence of posttransplant malignancies. Although there was no difference in graft or patient survival, immunosuppressive induction therapy with basiliximab yielded a significant reduction in the acute rejection rate.

Mycophenolate mofetil: ten years' experience of a renal transplant unit

Mycophenolate mofetil (MMF) use in renal transplantation has allowed a significant decrease in early acute rejection rates. We retrospectively evaluated the incidence of acute rejection episodes, renal function at the first year posttransplant, patient and graft survivals, cytomegalovirus (CMV) infection rate, influence of the degree of sensitization, and number of MHC antigen mismatches on graft survival in two groups of patients receiving either MMF or azathioprine. Group 1 included 149 patients receiving cyclosporine, MMF, and prednisolone; group 2 included 191 patients receiving cyclosporine, azathioprine, and prednisolone. The two groups did not differ in terms of age, sex, degree of sensitization (expressed as percentage of antibodies reactive to panel), MHC mismatch number, cold ischemia time, donor age, or anti-thymocyte globulin induction. In group 1 (MMF) there was a significant decrease in early acute rejection rate (19% vs 57%, P < .0001), longer graft survival at 10 years (92% vs 75%, P = .006), and higher rate of CMV infection (22% vs 12%, P = .004). Renal function at the first year posttransplant and patient survival during follow-up did not differ between the groups. The degree of sensitization influenced graft survival in group 2. The number of MHC mismatches did not influence graft survival in either group. With MMF, there was a significant reduction in early acute rejection rate, a significant increase in graft survival at 10-year follow-up, and diminished impact of the degree of sensitization on graft survival.

[The development of neurotoxic agents as chemical weapons during the National Socialist period in Germany]

INTRODUCTION

The discovery and development of the so-called 'nerve agents' (neurotoxic substances to be used as weapons) took place in the Third Reich, largely thanks to the vast amount of progress being made in pharmacology in Germany at that time, both in academic and industrial terms. Furthermore, successive National Socialist governments set up a collaborative network made up of the academia, the chemical industry and military chiefs that also favoured this line of research.

DEVELOPMENT

The first neurotoxic substance to be incorporated into the category of 'chemical warfare agent' did so almost wholly by chance. As part of the work being carried out on organophosphate-type pesticides and insecticides, Gerald Schrader, a chemist at the I.G. Farben company, synthesised tabun (ethyl N,N-dimethylphosphoramidocyanidate) and an incident involving accidental contamination of laboratory staff with this substance highlighted its potential toxicity. The same group of researchers later synthesised another substance with the same properties, sarin (isopropyl methylphosphonofluoridate). Both agents were studied for use as chemical weapons by Wolfgang Wirth. At the same time, a group led by Richard Kuhn, who won the Nobel Prize in Chemistry in 1938, synthesised pinacolyl methylphosphonofluoridate, otherwise known as soman.

CONCLUSIONS

Pharmacological studies confirmed that the neurotoxic mechanism of action of these substances was the irreversible inhibition of the enzyme acetylcholinesterase, which is responsible for metabolising acetylcholine. Results also showed that an excess of this neurotransmitter led to a continuous over-stimulation of the cholinergic (nicotinic and muscarinic) receptors, which is what triggers the appearance of the wide range of symptoms of poisoning and their swift fatal effect.

Solar TiO2-assisted photocatalytic degradation of IGCC power station effluents using a Fresnel lens

The heterogeneous TiO2 assisted photocatalytic degradation of wastewater from a thermoelectric power station under concentrated solar light irradiation using a Fresnel lens has been studied. The efficiency of photocatalytic degradation was determined from the analysis of cyanide and formate removal. Firstly, the influence of the initial concentration of H2O2 and TiO2 on the degradation kinetics of cyanides and formates was studied based on a factorial experimental design. Experimental kinetic constants were fitted using neural networks. Results showed that the photocatalytic process was effective for cyanides destruction (mainly following a molecular mechanism), whereas most of formates (degraded mainly via a radical path) remained unaffected. Finally, to improve formates degradation, the effect of lowering pH on their degradation rate was evaluated after complete cyanide destruction. The photooxidation efficiency of formates reaches a maximum at pH around 5-6. Above pH 6, formate anion is subjected to electrostatic repulsion with the negative surface of TiO2. At pH<4.5, formate adsorption and photon absorption are reduced due to some catalyst agglomeration.

Phase II of trastuzumab and cisplatin in patients (pts) with advanced gastric cancer (AGC) with HER2/neu overexpression/amplification

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Background: Trastuzumab(T) exhibits activity in human gastric cancer cells that overexpress HER2/neu. We previously reported a 13.5% HER2/neu overexpression/amplification in AGC or gastroesofageal junction (GEJ) cancers (Grávalos C, et al. J Clin Oncol 24, 18S, 200s, abstr # 4089). We designed a phase II trial to determine the efficacy and tolerability of T and cisplatin(C) in pts with ACG with HER2/neu overexpression/amplification. Exploratory objectives include analysis of c-erbB-2 extracellular domain and correlation of the results with histological erB-2/neu overexpression and with clinical response Methods: Chemo-naïve pts with adenocarcinoma histopatologically confirmed, HER2/neu overexpression/amplification, measurable, no operable, locally advanced or metastatic AGC, age ≥ 18, ECOG ≤ 2, FEVI ≥ 50% and adequate organ function were eligible. Prior adjuvant radiotherapy or/and chemotherapy were allowed. Immunohistochemistry (IHC) was performed using herceptest. A fluorescence in situ hybridization (FISH) assay was done when IHQ was = 2. HER2/neu expression was considered negative if IHC= 0, 1 or IHC=2 and FISH -; and positive if IHC=2 and FISH + or IHC=3. T 8 mg/kg d1 (loading dose in first cycle) and 6 mg/kg (maintenance doses) and C 75 mg/m2 d1 were administered every 21 days until progression, unacceptable toxicity or withdrawal inform consent Results: 21 pts has been included. 17 are evaluable. 16 were men. Median age 66 (50–78). ECOG 0/1: 5/12. Histological subtypes were: 50% intestinal, 25% diffuse and 25% unknown. 56% had gastric localization and 44% GEJ. 16 pts had metastases (59% liver, 47% lymph nodes, 23% peritoneum, 17% lung, and 24% others). Prior treatment: 5 pts underwent surgery and 2 had adjuvant chemotherapy. Median cycles 2 (1–14). Efficacy: 6 (35%) pts achieved response (1/5 CR/PR), 3 (17%) stabilization (52% control disease = RC + PR+SD), 4 pts with progression disease, 4 pts too early Tolerance: There was no grade 4 toxicity. Main grade 3 adverse events included: asthenia (3 pts), nauseas/vomiting (3), diarrhea (2), hiporexia (2) and neutropenia (1) Conclusions: Trastuzumab and cisplatin is a well tolerated regimen with a promising activity. The study is ongoing and an update will be presented at the meeting.

No significant financial relationships to disclose.

Life-threatening adverse drug reaction to paclitaxel. Postmarketing surveillance

The mechanism of action of hypersensitivity reactions from paclitaxel has not been fully understood. It has not even been defined if they are secondary to paclitaxel, its vehicle or the premedication. Postmarketing pharmacovigilance is predominantly based on spontaneous reporting. These reports albeit biased and incomplete serve to detect previously unrecognised adverse events. We report a life threatening adverse event related to paclitaxel without any evidence of histamine release. It consisted of a cardiac arrest probably secondary to bradiarrhythmia or branch block.

The relation between the erythrocyte nitric oxide and hemorheological parameters

We stimulated human erythrocytes obtained from patients with hypercholesterolemia (HC; n = 42), renal transplantation (RT; n = 18) and hypertension (HT; n = 10) with acetylcholine (ACh 10 microM) and measured the amperometric NO production, comparing with the NO levels achieved on erythrocytes of healthy persons (n = 27). We also measured the hemoglobin, hematocrit, erythrocyte aggregation, erythrocyte deformability, plasma viscosity and fibrinogen concentration from human blood samples. The erythrocytes NO levels were of 2.5 +/- 0.7 nM (P = 0.038, HC), 2.4 +/- 1.1 nM (RT) and 2.2 +/- 0.8 nM (HT) against the 2.0 +/- 0.8 nM for the control groups. For each group and at each shear stress value, the erythrocytes deformability decreases with the increase of the NO concentration after ACh stimulation. We observed a significant increase of the control values on the erythrocyte aggregation results on each patient group. Besides the lower erythrocyte deformability obtained on HC, RT and HT blood samples, the erythrocytes produced higher NO levels after ACh stimulation than the healthy ones. The power of erythrocyte hemorheological behaviour could be compensated by the NO production at the presence of acetylcholine. We can hypothesises that cholinergic drugs could be used as co-adjuvants of specific therapeutics compounds on these studied diseases.

Impact of donor and recipient cytokine genotypes on renal allograft outcome

Allelic differences in gene promoter or codifying regions have been described to affect regulation of gene expression, consequently increasing or decreasing cytokine production and signal transduction responses to a given stimulus. This observation has been reported for interleukin (IL)-10 (-1082 A/G; -819/-592 CT/CA), transforming growth factor (TGF)-beta (codon 10 C/T, codon 25 G/C), tumor necrosis factor (TNF)-alpha (-308 G/A), TNF-beta (+252 A/G), interferon (IFN)-gamma (+874 T/A), IL-6 (-174 G/C), and IL-4R alpha (+1902 G/A). To evaluate the influence of these cytokine genotypes on the development of acute or chronic rejection, we correlated the genotypes of both kidney graft recipients and cadaver donors with the clinical outcome. Kidney recipients had 5 years follow-up, at least 2 HLA-DRB compatibilities, and a maximum of 25% anti-HLA pretransplantation sensitization. The clinical outcomes were grouped as follows: stable functioning graft (NR, n = 35); acute rejection episodes (AR, n = 31); and chronic rejection (CR, n = 31). The cytokine genotype polymorphisms were defined using PCR-SSP typing. A statistical analysis showed a significant prevalence of recipient IL-10 -819/-592 genotype among CR individuals; whereas among donors, the TGF-beta codon 10 CT genotype was significantly associated with the AR cohort and the IL-6 -174 CC genotype with CR. Other albeit not significant observations included a strong predisposition of recipient TGF-beta codon 10 CT genotype with CR, and TNF-beta 252 AA with AR. A low frequency of TNF-alpha -308 AA genotype also was observed among recipients and donors who showed poor allograft outcomes.

Molecular phylogeography of the moss Tortula muralis Hedw (Pottiaceae) based on chloroplast rps4 gene sequence data

Tortula muralis is a moss species of cosmopolitan distribution, for which we present chloroplast rps4 sequence data. The sequences provided a sufficiently high degree of divergence ( h = 0.878, theta = 0.00989 +/- 0.0000106, a total of 18 haplotypes for 49 accessions) for the degree of differentiation between regions from different continents to be investigated. In fact, 18.53 % of the variation found corresponded to differences between these regions, while 81.43 % was attributed to intra-region differences. Only the Japanese area differed significantly from other regions. Some haplotypes are found on several continents, while others are restricted to certain areas. Six of the seven sequenced plants from Japan belong to a haplotype only found there. The phylogenetic analysis suggests that Tortula muralis might be paraphyletic, with Tortula vahliana nested within the Tortula muralis clade. At present, it is not clear whether gene flow between the different clades of Tortula muralis is a continuing process or whether Tortula muralis is an example of cryptic speciation.

A new cervical spine clearance protocol using computed tomography

OBJECTIVE

The purpose of this study was to assess a cervical spine clearance protocol for blunt trauma patients using helical computed tomographic (CT) scan of the cervical spine (C-spine).

METHODS

A protocol using CT scan of the C-spine was implemented and the first 6 months of use reviewed. Patients requiring a CT scan of the head had the C-spine evaluated by lateral C-spine radiography and a helical CT scan. Patients without indication for CT scan of the head had the C-spine evaluated by three-view radiography (anteroposterior, lateral, and odontoid) with selective CT scan of the C-spine for imaging areas not well visualized or those with abnormalities identified by radiography or by clinical examination alone.

RESULTS

Three hundred twenty-four patients were admitted to the trauma center after blunt trauma during the first 6 months of protocol implementation. Head CT scans were obtained in 158 patients and lateral cervical spine radiography in conjunction with helical CT scanning evaluated the C-spine. The other 166 patients had the cervical spine cleared by three-view radiography series or by clinical examination alone. For patients in whom a head CT scan was not indicated, CT scanning was used only when plain radiographs failed to adequately visualize the entire C-spine. A total of 15 injuries (4.6% of the group) were detected. Seven injuries were suspected or detected by lateral plain radiographs and confirmed by CT scan. Six patients had an injury not detected by radiography but diagnosed by CT scan, and one patient had a false-positive radiograph. Of the remaining two injuries, one was diagnosed by magnetic resonance imaging and the other by CT scan outside of the protocol. Lateral plain radiographs alone failed to detect 46% (n = 6) of all injuries.

CONCLUSION

In our series, the selective use of helical CT scanning with plain radiography increased the accuracy with which cervical spine injury was detected from 54% to 100%. The protocol allowed for more rapid evaluation in many patients as well. We recommend that practice guidelines include the use of helical CT scan of the entire C-spine as the diagnostic procedure for those blunt trauma patients undergoing CT scanning of the head.