High cut-off haemodialysis induces remission of recurrent idiopathic focal segmental glomerulosclerosis after renal transplantation but is no alternative to plasmapheresis

A 26-year-old male experienced a recurrence of idiopathic focal segmental glomerulosclerosis (iFSGS) after his second renal transplant. Reduction of proteinuria was rapidly induced by plasmapheresis (PP) and the patient has remained in remission with a once-weekly PP regimen, which has now been continued for >3½ years. We were also able to induce remission of iFSGS in this patient by treatment with high cut-off haemodialysis using the Theralite™ dialyser. This observation lends support for the pathophysiological role of an as yet unknown, circulating glomerular filtration barrier permeability factor with an estimated weight of between 30 and 50 kDa

Material Characterization and Design Recommendations for Mechanically Stabilized Earth Retaining Walls

Since its appearance in 1970s, mechanically stabilized earth (MSE) walls have become a majority among all types of retaining walls due to their economics and satisfactory performance. The Texas Department of Transportation has primarily adopted the Federal Highway Administration and American Association of State Highway and Transportation Officials (AASHTO) guidelines for design of MSE walls. The research addresses three main issues expressed by TxDOT in their design and material selection process. The literature review in this research addresses the current practice and guidelines adopted by TxDOT as well as other Department of Transportations. The first part of this dissertation explains the laboratory test performed on backfill materials used in Texas. The material classification was carried out according to TxDOT specifications and the laboratory test consist of performing state-of-the-art large scale triaxial test on large particles to evaluate engineering properties of backfill materials and a consolidated undrained test on a backfill material with higher amount fine particles present in that soil. The second part of this addresses the issues on global stability and failure modes associated with it. A Fast Lagrangian Analysis of Continua (FLAC) program was used to asseses possible failure modes for MSE walls with different geometries and soil parameters for retained and foundation soils. Finally, a parametric study was performed for sliding analysis using AASTHO recommended design parameters and comparing them with modified design parameters calculated from FLAC simulations for different geometries and soil parameters. Similarly, a parametric study was performed to address bearing capacity issues for MSE walls and justification of AASHTO recommendation with German code (EBGEO) for MSE walls. The outcome this research shows that, the friction angle () for the backfill materials used in Texas is higher than AASHTO recommended values for large particles size type backfills. From FLAC simulations it shows that the global failure mechanism for MSE walls is dependent on type of soil properties used as retained and foundation soils. The parametric study shows that a modified parameters can be used for sliding analysis and for bearing capacity analysis a combination of Vesic’s and German code can be used

Wireless Monitoring of Railway Embankments

Landslides are one of the most dangerous geological hazards. In the United States, landslides cause a damage of $ 3.5 billion and kill 25 to 50 people annually. Shallow landslides occurring near any transportation facilities (railways and highways) can cause economic loss and disturbance of services which lead to indirect economic loss. It also increases the maintenance cost of those facilities. Hence, facilities located near a shallow landslide prone area should be monitored so as to avoid any catastrophic damages. Soil moisture and movement of the soil mass are prime indicators of potential shallow slide movements. This assessment of wireless instruments considers a variety of devices ranging from devices for monitoring tilt and moisture at specific points in the soil mass to ground penetrating radar (GPR), which can give indications of moisture accumulation in soils over a wide spatial extent. For this assessment study, a low cost MEMS accelerometer was selected for measuring tilts and motions. And EC type soil moisture sensor was selected to measure soil moisture content of embankments. The instrumentation of railway embankments works effectively and cheaply when a suspected problem area has already been identified and monitoring is needed over a limited spatial extent. This makes the monitoring system highly localized which often fails to cover potentially new failure prone areas. It is not feasible to use this approach to monitor soil conditions along the entire alignment of the railway. Therefore, another approach, GPR, is defined and explained in this study. GPR measures the dielectric constant value for any given material including soils. In soils, the dielectric constant value depends on the volumetric amount of water content present in a soil. Due to moisture infiltration, there is a reduction in suction value on embankment which indicates a decrease in shear strength of slope. Therefore, a correlation between suction and dielectric constant value is formulated in this study using Complex Refractive index model/Time propagation (CRIM/TP) model for soils. To validate this theoretical correlation, a laboratory study was conducted on pure kaolinite and on normal soil. For pure kaolinite this correlation proves beneficial while, for other type of soil, the correlation was off due to the limitations in filter paper test to measure suction below 2.5pF

Clinical and epidemiological assessment of steroid-resistant nephrotic syndrome associated with the NPHS2 R229Q variant

Mutations of NPHS2, encoding podocin, are the main cause of autosomal recessive steroid-resistant nephrotic syndrome (NS) presenting in childhood. Adult-onset steroid-resistant NS has been described in patients heterozygous for a pathogenic NPHS2 mutation together with the p.R229Q variant. To determine the frequency and the phenotype of patients carrying the p.R229Q variant, we sequenced the complete coding region of NPHS2 in 455 families (546 patients) non-responsive to immunosuppressive therapy or without relapse after transplantation. Among affected Europeans, the p.R229Q allele was significantly more frequent compared to control individuals. Thirty-six patients from 27 families (11 families from Europe and 14 from South America) were compound heterozygotes for the p.R229Q variant and one pathogenic mutation. These patients had significantly later onset of NS and end stage renal disease than patients with two pathogenic mutations. Among 119 patients diagnosed with NS presenting after 18 years of age, 18 patients were found to have one pathogenic mutation and p.R229Q, but none had two pathogenic mutations. Our study shows that compound heterozygosity for p.R229Q is associated with adult-onset steroid-resistant NS, mostly among patients of European and South American origin. Screening for the p.R229Q variant is recommended in these patients along with further NPHS2 mutation analysis in those carrying the variant

Cancer incidence in kidney transplant recipients: a study protocol

<p>Abstract</p> <p>Background</p> <p>Different publications show an increased incidence of neoplasms in renal transplant patients. The objective of this study is to determine the incidence of cancer in the recipients of renal transplants performed in the A Coruña Hospital (Spain) during the period 1981–2007.</p> <p>Methods/Design</p> <p>During the study period 1967 kidney transplants were performed, corresponding to 1710 patients. Patients with neoplasms prior to the transplant will be excluded (n = 38). A follow-up study was carried out in order to estimate cancer incidence after transplantation.</p> <p>For each patient, information included donor and recipient characteristics, patients and graft survival and cancer incidence after transplantation. Incident cancer is considered as new cases of cancer after the transplant with anatomopathological confirmation. Their location will be classified according to the ICD-9.</p> <p>The analysis will be calculated using the indirect standardisation method. Age-adjusted cancer incidence rates in the Spanish general population will be obtained from the Carlos III Health Institute, the National Epidemiology Centre of the Ministry of Science and Technology. Crude first, second and third-year post-transplantation cancer incidence rates will be calculated for male and female recipients. The number of cases of cancer at each site will be calculated from data in the clinical records. The expected number of cancers will be calculated from data supplied by the Carlos III Health Institute. For each tumour location we will estimate the standardized incidence ratios (SIRs), using sex-specific cancer incidence rates, by dividing the incidence rate for the transplant patients by the rate of the general population. The 95% confidence intervals of the SIRs and their associated p-values will be calculated by assuming that the observed cancers follow a Poisson distribution. Stratified analysis will be performed to examine the variation in the SIRs with sex and length of follow-up.</p> <p>Competing risk survival analysis methods will be applied to estimate the cumulative incidence of cancer and to identify variables associated to its occurrence.</p> <p>Discussion</p> <p>Information about cancer incidence in kidney transplant patients could be useful to adapt the guidelines on post-kidney transplant follow-up on tumour screening, and evaluate the impact of intervention measures for the prevention of cancer in these patients.</p

The Involvement of SMILE/TMTC3 in Endoplasmic Reticulum Stress Response

The state of operational tolerance has been detected sporadically in some renal transplanted patients that stopped immunosuppressive drugs, demonstrating that allograft tolerance might exist in humans. Several years ago, a study by Brouard et al. identified a molecular signature of several genes that were significantly differentially expressed in the blood of such patients compared with patients with other clinical situations. The aim of the present study is to analyze the role of one of these molecules over-expressed in the blood of operationally tolerant patients, SMILE or TMTC3, a protein whose function is still unknown.We first confirmed that SMILE mRNA is differentially expressed in the blood of operationally tolerant patients with drug-free long term graft function compared to stable and rejecting patients. Using a yeast two-hybrid approach and a colocalization study by confocal microscopy we furthermore report an interaction of SMILE with PDIA3, a molecule resident in the endoplasmic reticulum (ER). In accordance with this observation, SMILE silencing in HeLa cells correlated with the modulation of several transcripts involved in proteolysis and a decrease in proteasome activity. Finally, SMILE silencing increased HeLa cell sensitivity to the proteasome inhibitor Bortezomib, a drug that induces ER stress via protein overload, and increased transcript expression of a stress response protein, XBP-1, in HeLa cells and keratinocytes.In this study we showed that SMILE is involved in the endoplasmic reticulum stress response, by modulating proteasome activity and XBP-1 transcript expression. This function of SMILE may influence immune cell behavior in the context of transplantation, and the analysis of endoplasmic reticulum stress in transplantation may reveal new pathways of regulation in long-term graft acceptance thereby increasing our understanding of tolerance

Developmental Splicing Deregulation in Leukodystrophies Related to EIF2B Mutations

Leukodystrophies (LD) are rare inherited disorders that primarily affect the white matter (WM) of the central nervous system. The large heterogeneity of LD results from the diversity of the genetically determined defects that interfere with glial cells functions. Astrocytes have been identified as the primary target of LD with cystic myelin breakdown including those related to mutations in the ubiquitous translation initiation factor eIF2B. EIF2B is involved in global protein synthesis and its regulation under normal and stress conditions. Little is known about how eIF2B mutations have a major effect on WM. We performed a transcriptomic analysis using fibroblasts of 10 eIF2B-mutated patients with a severe phenotype and 10 age matched patients with other types of LD in comparison to control fibroblasts. ANOVA was used to identify genes that were statistically significantly differentially expressed at basal state and after ER-stress. The pattern of differentially expressed genes between basal state and ER-stress did not differ significantly among each of the three conditions. However, 70 genes were specifically differentially expressed in eIF2B-mutated fibroblasts whatever the stress conditions tested compared to controls, 96% being under-expressed. Most of these genes were involved in mRNA regulation and mitochondrial metabolism. The 13 most representative genes, including genes belonging to the Heterogeneous Nuclear Ribonucleoprotein (HNRNP) family, described as regulators of splicing events and stability of mRNA, were dysregulated during the development of eIF2B-mutated brains. HNRNPH1, F and C mRNA were over-expressed in foetus but under-expressed in children and adult brains. The abnormal regulation of HNRNP expression in the brain of eIF2B-mutated patients was concomitant with splicing dysregulation of the main genes involved in glial maturation such as PLP1 for oligodendrocytes and GFAP in astrocytes. These findings demonstrate a developmental deregulation of splicing events in glial cells that is related to abnormal production of HNRNP, in eIF2B-mutated brains

Disease recurrence in paediatric renal transplantation

Renal transplantation (Tx) is the treatment of choice for end-stage renal disease. The incidence of acute rejection after renal Tx has decreased because of improving early immunosuppression, but the risk of disease recurrence (DR) is becoming relatively high, with a greater prevalence in children than in adults, thereby increasing patient morbidity, graft loss (GL) and, sometimes, mortality rate. The current overall graft loss to DR is 7–8%, mainly due to primary glomerulonephritis (70–80%) and inherited metabolic diseases. The more typical presentation is a recurrence of the full disease, either with a high risk of GL (focal and segmental glomerulosclerosis 14–50% DR, 40–60% GL; atypical haemolytic uraemic syndrome 20–80% DR, 10–83% GL; membranoproliferative glomerulonephritis 30–100% DR, 17–61% GL; membranous nephropathy ∼30% DR, ∼50% GL; lipoprotein glomerulopathy ∼100% DR and GL; primary hyperoxaluria type 1 80–100% DR and GL) or with a low risk of GL [immunoglobulin (Ig)A nephropathy 36–60% DR, 7–10% GL; systemic lupus erythematosus 0–30% DR, 0–5% GL; anti-neutrophilic cytoplasmic antibody (ANCA)-associated glomerulonephritis]. Recurrence may also occur with a delayed risk of GL, such as insulin-dependent diabetes mellitus, sickle cell disease, endemic nephropathy, and sarcoidosis. In other primary diseases, the post-Tx course may be complicated by specific events that are different from overt recurrence: proteinuria or cancer in some genetic forms of nephrotic syndrome, anti-glomerular basement membrane antibodies-associated glomerulonephritis (Alport syndrome, Goodpasture syndrome), and graft involvement as a consequence of lower urinary tract abnormality or human immunodeficiency virus (HIV) nephropathy. Some other post-Tx conditions may mimic recurrence, such as de novo membranous glomerulonephritis, IgA nephropathy, microangiopathy, or isolated specific deposits (cystinosis, Fabry disease). Adequate strategies should therefore be added to kidney Tx, such as donor selection, associated liver Tx, plasmatherapy, specific immunosuppression protocols. In such conditions, very few patients may be excluded from kidney Tx only because of a major risk of DR and repeated GL. In the near future the issue of DR after kidney Tx may benefit from alternatives to organ Tx, such as recombinant proteins, specific monoclonal antibodies, cell/gene therapy, and chaperone molecules