Search

Seismic noise recorded at the surface of Mars has been monitored since February 2019, using the InSight seismometers.This noise can reach -200 dB and is 500 times lower than on Earth at night and it increases of 30 dB during the day. We analyze its polarization as a function of time and frequency in the band 0.03-1Hz. We use the degree of polarization to extract signals with stable polarization independent of their amplitude and type of polarization. We detect polarized signals at all frequencies and all times. Glitches correspond to linear polarized signals which are more abundant during the night. For signals with elliptical polarization, the ellipse is in the horizontal plane below 0.3 Hz (LF). Above 0.3 Hz (HF) and except in the evening, the ellipse is in the vertical plane and the major axis is tilted. While polarization azimuths are different in the two frequency bands, they both vary as a function of local hour and season. They are also correlated with wind direction, particularly during the daytime.We investigate possible aseismic and seismic origins of the polarized signals. Lander or tether noise can be discarded. Pressure fluctuations transported by wind may explain part of the HF polarization but not the tilt of the ellipse. This tilt can be obtained if the source is an acoustic emission coming from high altitude at critical angle. Finally, in the evening when the wind is low, the polarized signals may correspond to the seismic wavefield of the Mars background noise.

International audience; One of the goals of the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission is to constrain the interior structure of Mars. We present a hierarchical transdimensional Bayesian approach to extract phase velocity dispersion and interior shear‐wave velocity (VS) models from a single seismogram. This method was adapted to Mars from a technique recently developed for Earth (Xu & Beghein, 2019, https://doi.org/10.1093/gji/ggz133). Monte Carlo Markov Chains seek an ensemble of one dimensional (1‐D) VS models between a source and a receiver that can explain the observed waveform. The models obtained are used to calculate the phase velocities of fundamental and higher modes at selected periods, and a subsequent analysis is performed to assess which modes were reliably measured. An advantage of our approach is that it can also fit unknown data noise, which reduces the risk of overfitting the data. In addition, uncertainties in the source parameters can be propagated, yielding more accurate model parameter uncertainties. In this study, we first present our technique and discuss the challenges stemming from using a single station to characterize both structure and the source and from the absence of a Mars reference model. We then demonstrate the method feasibility using the Mars Structure Service blind test data and our own synthetic data, which included realistic noise levels based on the noise recorded by InSight.

Seismic noise recorded at the surface of Mars has been monitored since February 2019, using the InSight seismometers. This noise can reach -200 dB. It is 500 times lower than on Earth at night and it increases of 30 dB during the day. We analyze its polarization as a function of time and frequency in the band 0.03-1 Hz. We use the degree of polarization to extract signals with stable polarization independent of their amplitude and type of polarization. We detect polarized signals at all frequencies and all times. Glitches correspond to linear polarized signals which are more abundant during the night. For signals with elliptical polarization, the ellipse is in the horizontal plane below 0.3 Hz. In the 0.3-1Hz high frequency band (HF) and except in the evening, the ellipse is in the vertical plane and the major axis is tilted. While polarization azimuths are different in the two frequency bands, they both vary as a function of local hour and season. They are also correlated with wind direction, particularly during the daytime. We investigate possible aseismic and seismic origins of the polarized signals. Lander or tether noise can be discarded. Pressure fluctuations transported by wind may explain part of the HF polarization but not the tilt of the ellipse. This tilt can be obtained if the source is an acoustic emission coming from high altitude at critical angle. Finally, in the evening when the wind is low, the measured polarized signals may correspond to the seismic wavefield of the Mars background noise. Plain Language Summary Seismic noise at the surface of Mars was unknown until the first measurements by the seismometers from the InSight mission in January 2019. On Earth, the microseismic noise (0.05-1 Hz) is composed dominantly of surface waves generated by the numerous sources related to ocean wave activities. On Mars, because there is no ocean, seismic noise is down to 500 times lower than on Earth reaching -200 dB in acceleration at night. In order to determine the nature of the Mars noise, we analyze its polarization with a statistical method and show that it is different to that on Earth. In the low frequency band 0.03-0.3 Hz, we detect signals with elliptical polarization in the horizontal plane. In the high frequency band 0.3-1Hz (HF), signals have elliptical polarization in the vertical plane. The polarization ellipse azimuth gives the direction toward the source. On Mars, these azimuths are varying as a function of local hour and season and they are correlated with wind direction during the daytime. The HF polarized signals may be explained by local effects of pressure fluctuations and/or by acoustic emission coming from high altitudes in particular conditions. It is only in the evening when the wind is low, that the measured polarized signals may correspond to propagating seismic waves that would be the Mars seismic background noise., This is the InSight contribution number 143 and IPGP contribution number 4183. We acknowledge NASA, CNES, their partner agencies and institutions (UKSA, SSO, DLR, JPL, IPGP-CNRS, ETHZ, IC, MPS-MPG) and the flight operations team at JPL, SISMOC, MSDS, IRIS-DMC, and PDS for providing SEED SEIS data. French authors are supported by ANR MAGIS (ANR-19-CE31-0008-08) and by CNES for SEIS science support. A. Horleston is supported by the UK Space Agency through grant #ST/R002096/1. M. Schimmel is supported by the SANIMS project (RTI2018-095594-B-I00, MICINN, Spain).

The InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) lander will deploy a seismic monitoring package on Mars in November 2018. In prepara- tion for the data return, we prepared a blind test in which we invite participants to detect and characterize seismicity included in a synthetic dataset of continuous waveforms from a single station that mimics both the streams of data that will be available from InSight, as well as expected tectonic and impact seismicity and noise conditions on Mars. We expect that the test will ultimately improve and extend the current set of methods that the InSight team plan to use in routine analysis of the Martian dataset.

By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars’ surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking’s Mars seismic monitoring by a factor of ∼2500 at 1 Hz and ∼200000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars’ surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of Mw∼3 at 40∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution., Space Science Reviews, 215 (1), ISSN:1572-9672, ISSN:0038-6308

International audience; Although not the prime focus of the InSight mission, the near-surface geology and physical properties investigations provide critical information for both placing the instruments (seismometer and heat flow probe with mole) on the surface and for understanding the nature of the shallow subsurface and its effect on recorded seismic waves. Two color cameras on the lander will obtain multiple stereo images of the surface and its interaction with the spacecraft. Images will be used to identify the geologic materials and features present, quantify their areal coverage, help determine the basic geologic evolution of the area, and provide ground truth for orbital remote sensing data. A radiometer will measure the hourly temperature of the surface in two spots, which will determine the thermal inertia of the surface materials present and their particle size and/or cohesion. Continuous measurements of wind speed and direction offer a unique opportunity to correlate dust devils and high winds with eolian changes imaged at the surface and to determine the threshold friction wind stress for grain motion on Mars. During the first two weeks after landing, these investigations will support the selection of instrument placement locations that are relatively smooth, flat, free of small rocks and load bearing. Soil mechanics parameters and elastic properties of near surface materials will be determined from mole penetration and thermal conductivity measurements from the surface to 3–5 m depth, the measurement of seismic waves during mole hammering, passive monitoring of seismic waves, and experiments with the arm and scoop of the lander (indentations, scraping and trenching). These investigations will determine and test the presence and mechanical properties of the expected 3–17 m thick fragmented regolith (and underlying fractured material) built up by impact and eolian processes on top of Hesperian lava flows and determine its seismic properties for the seismic investigation of Mars’ interior.

Vesicoureteric reflux (VUR) is the commonest urological anomaly in children. Despite treatment improvements, associated renal lesions - congenital dysplasia, acquired scarring or both - are a common cause of childhood hypertension and renal failure. Primary VUR is familial, with transmission rate and sibling risk both approaching 50%, and appears highly genetically heterogeneous. It is often associated with other developmental anomalies of the urinary tract, emphasising its etiology as a disorder of urogenital tract development. We conducted a genome-wide linkage and association study in three European populations to search for loci predisposing to VUR. Family-based association analysis of 1098 parent-affected-child trios and case/control association analysis of 1147 cases and 3789 controls did not reveal any compelling associations, but parametric linkage analysis of 460 families (1062 affected individuals) under a dominant model identified a single region, on 10q26, that showed strong linkage (HLOD = 4.90; ZLRLOD = 4.39) to VUR. The ~9Mb region contains 69 genes, including some good biological candidates. Resequencing this region in selected individuals did not clearly implicate any gene but FOXI2, FANK1 and GLRX3 remain candidates for further investigation. This, the largest genetic study of VUR to date, highlights the 10q26 region as a major genetic contributor to VUR in European populations.

It has been suggested that C1q and immunoglobulin M (IgM) nephropathy are variants of minimal change nephrotic syndrome (MCNS). Many researchers believe that these two conditions signify a worse prognosis for children with MCNS in comparison with immunofluorescence (IF)-negative MCNS. The aim of our study was to determine the prognostic significance of C1q nephropathy and IgM nephropathy in children with MCNS.Fifty-five children with MCNS who had been biopsied over the course of 24 years at our institution were retrospectively categorized into three groups on the basis of IF microscopy findings: IF-negative MCNS (29/55 patients), MCNS with IgM nephropathy (19/55 patients), and MCNS with C1q nephropathy (7/55 patients). Clinical characteristics at disease presentation, clinical course, and renal outcome were compared between groups during the median follow-up period of 16.9 years (minimum 1.0, maximum 31.1 years).No statistically significant differences in clinical characteristics at disease presentation, clinical course, and renal outcome were found. Children with IgM nephropathy, C1q nephropathy, and IF-negative MCNS were clinically indistinguishable.We concluded that C1q or IgM nephropathy variants do not seem to signify a worse prognosis in children with MCNS in comparison with IF-negative MCNS.

Our aim was to evaluate the efficacy of our treatment program for children with lower urinary tract conditions, developed at the Department of Pediatric Nephrology of the University Children’s Hospital in Ljubljana. Sixty-four patients with lower urinary tract conditions were randomly allocated to two groups. Group A received treatment immediately, whereas patients of group B received no treatment for a period of 3 months—the amount of time it takes to complete our program. No child in group B experienced spontaneous regression of their symptoms in the 3-month delay period, while the patients of group A were already being treated and were achieving results. Thus, all the patients of group B then entered the program in exactly the same way as patients of group A. The final success rate in both groups did not differ significantly (p = 0.706–1.000) and ranged from 86.2 % for group A and 86.7 to 90 % for group B. Long-term follow-up showed statistically identical success rates (p = 1.000). This prospective controlled study with long-term follow-up (48 months) shows that our treatment program, applied as an inpatient voiding school program, is an effective method, with durable results.

We present different ultrasound techniques to detect vesicoureteral reflux in children with special emphasis on voiding urosonography.Urinary tract infection is a common problem in children that may be related to vesicoureteral reflux. Currently there is no consensus on investigations in children after the first urinary tract infection. The least invasive imaging with the smallest radiation burden should be used in children. Ultrasound to detect reflux meets several of these criteria. The development of echo enhancing agents has markedly improved reflux visualization by ultrasound.We discuss the clinical relevance of voiding urosonography. We reviewed the currently available literature and the results of our studies of this issue. We also describe our endeavors to avoid catheterization and detect vesicoureteral reflux based on various sonomorphological features, ie indirect voiding urosonography and ureteral jet Doppler waveform analysis, to avoid applying any substance into the bladder.Voiding urosonography is safe and reliable to detect vesicoureteral reflux. When indicated, considerably decreased radiation exposure can be achieved by voiding urosonography instead of established cystography methods. Indirect voiding urosonography and ureteral jet Doppler waveform analysis could be an alternative to invasive voiding cystography, at least in children older than 3 years.

In recent years, the exact role of vesicoureteric reflux (VUR) in general has become controversial, though in some groups of children the knowledge of the existence or non-existence of VUR is still a very important issue. The number of techniques available for the assessment of VUR is increasing, and a new classification taking into account their real characteristics (direct/indirect, catheter-using/catheter-free, radiation-giving/radiation-free) has been proposed. The purpose of the following review is to evaluate the currently available evidence supporting the use of various catheter-free methods for VUR detection. We believe that as the clinical role of VUR has been questioned, it is even more important for the method of its detection to be user-friendly as regards catheterisation, radiation and availability. There is still no evidence supporting the assertion that any of the catheter-free methods of VUR detection might be the optimal one for any child. However, there are some groups of children who would benefit from using them. New studies using new, catheter-free methods of VUR detection or a combination of two or more of the methods described may prove useful in improving sensitivity and providing additional data on this important issue.

UNLABELLED Real-time ultrasound-guided renal biopsy (RB) with a biopsy gun has become a standard procedure in the treatment of children. The purpose of the study was to establish the complication rate after real-time ultrasound-guided RB with a biopsy gun, the adequacy of renal tissue samples for pathohistological tests, the rate of concurrence between clinical and pathohistological diagnoses, and the benefits of the procedure. From January 1994 to October 1999, 88 renal biopsies were performed on 82 children, 81 of whom (35M, 46F, aged 3-20 y) were included in this retrospective study. The nephrotic syndrome (in infants, older children, those with evidence of nephritis or failing corticosteroid therapy) was the most frequent indication of RB. Other indications were non-nephrotic proteinuria, nephritic syndrome, glomerular haematuria, renal allograft dysfunction, unexplained acute or chronic renal failure, and kidney disease progression monitoring. No serious complications were noted. The adequacy rate of renal tissue samples ranged from 93.1 to 96.6%, depending on which definition of the adequacy of renal tissue samples was used. Clinical and pathohistological diagnoses matched in 81.4% of the cases. Data obtained by RB were very beneficial to patients in terms of establishing, confirming or altering the diagnosis and, consequently, the treatment. CONCLUSION The results confirm that real-time ultrasound-guided RB with a biopsy gun is a safe procedure and provides information that is very beneficial to patients.

C1q nephropathy (C1qNP) is a peculiar form of glomerulonephritis characterized by mesangial immunoglobulin and complement deposits, predominantly C1q, with no evidence of systemic lupus erythematosus. We describe the incidence, manifestation, histopathologic findings, follow-up, treatment and outcome of C1qNP. Twelve C1qNP patients were identified among 131 children who had undergone renal biopsy, accounting for a 9.16% incidence of C1qNP. Light microscopy examination showed focal segmental glomerulosclerosis (FSGS) with or without diffuse mesangial proliferation (n=6), minimal change disease (MCD) (n=4) or focal glomerulonephritis (n=2). C1q deposits were found in all, while electron microscopy revealed visible deposits in nine cases. Eight children presented with nephrotic syndrome, while one had nephrotic proteinuria and renal insufficiency that progressed to end-stage renal failure. The remaining three patients presented with nonnephrotic proteinuria associated with microhematuria, hypertension or renal insufficiency. Only one nephrotic syndrome patient responded excellently to corticosteroids, while four became corticosteroid dependent, and three were corticosteroid resistant, showing a very poor response to other immunosuppressive therapy as well. Patients with non-nephrotic proteinuria demonstrated fixed laboratory findings. Most C1qNP patients had FSGS or MCD, the majority of them presenting with corticosteroid-dependent or corticosteroid-resistant nephrotic syndrome. The latter showed a very poor response to any immunosuppressive therapy and high risk for progressive renal insufficiency.

Three methods are currently used to identify vesicoureteral reflux (VUR) in children, namely X-ray voiding cystourethrography (VCUG), radionuclide voiding cystography (RVC), and, recently, echo-enhanced voiding urosonography (VUS). It is known that the sensitivity of VCUG and RVC for detecting VUR can be improved by using cyclic procedures, such as repeated bladder filling and voiding. The purpose of our prospective study was to evaluate whether the cyclic procedure is superior to the conventional (one cycle only) procedure in VUS also. VUS was performed in 49 patients, aged 1.4-15.8 years (mean 4.1 years). After the first micturition, the catheter was left in place and the whole procedure was repeated under the same conditions. The results of the first and second cycles and the combined procedure were compared. In the initial cycle, 7 of 35 (20%) refluxing renal units that were detected in the second cycle and 4 of 26 (15%) children with at least unilateral VUR were missed. Cyclic VUS detected 25% more VURs than the conventional (one cycle only) VUS ( P=0.049) and revealed 50% more VUR III than the first cycle. Our results suggest that cyclic VUS is superior to conventional VUS.

The aim of this study was to investigate whether erythrocyte deformability is higher in otherwise healthy children and adolescents with asymptomatic isolated glomerular microhematuria and no clinical or laboratory signs indicating renal disorder. Erythrocyte deformability in 33 children and adolescents with unexplained asymptomatic isolated glomerular microhematuria (study group) was compared with erythrocyte deformability in 133 individuals without urinary tract disease and without microhematuria (control group), 26 patients with microhematuria and IgA nephropathy (IgA nephropathy group), and 31 children and adolescents with benign familial hematuria (benign familial hematuria group). The erythrocyte and buffer filtration time was measured, the erythrocyte-to-buffer filtration time ratio calculated, and, on the basis thereof, erythrocyte deformability was estimated as an inverse proportion of the erythrocyte-to-buffer filtration time ratio in all subjects. The erythrocyte-to-buffer filtration time ratio increased with age in all groups (P

Aim: We investigate the effects of local training on the forearm vessels in patients with end-stage renal disease. Methods: Fourteen hemodialysis patients were included. Handgrip training was performed for 8 weeks. The following parameters were measured at the beginning of the study and 4 and 8 weeks later: forearm circumference, maximal handgrip strength, and artery and vein parameters, including endothelium-dependent and endothelium-independent vasodilatation (using ultrasound and duplex Doppler scanning). Results: The maximal handgrip strength increased significantly. The radial artery diameters were significantly higher after 8 weeks of training. The endothelium-dependent vasodilatation was found to be significantly increased after 4 and 8 weeks of training. The maximal vein diameters increased significantly with training, with preserved distensibility. Conclusions: The present study suggests that regular handgrip training increases the diameters of forearm vessels. It also improves endothelium-dependent vasodilatation. These changes point to the possible beneficial effects of daily handgrip training in chronic renal failure patients before arteriovenous fistula construction.

Renal parenchymal defects (RPD) -- scars, hypoplasia/dysplasia -- in children are a major risk factor for chronic renal failure. Most authors would agree that RPD should be detected and followed by a 99mTc-dimercaptosuccinic acid renal scan (DMSA), as ultrasonography (US) does not seem to be sensitive enough for this purpose. However, it might well be that DMSA is too sensitive and detects RPD that are too small to be clinically significant. The purpose of this study was to evaluate the sensitivity of US in identifying patients with clinically significant RPD and in detecting RPD of various grades as seen by DMSA. In 89 children with abnormal DMSA, a second DMSA, US, and other tests for evaluating renal function were performed at least 1 year after the first DMSA. The extent of RPD detected by DMSA and US was correlated with renal function parameters. In all 5 patients with diminished renal function, RPD were detected by both DMSA scan and US. In addition, US detected clinically insignificant RPD in 48 of 67 cases (71.6%). The present study has shown that, compared with DMSA, US is sensitive enough to detect clinically significant RPD in children. The substitution of DMSA with US would be beneficial, as this would eliminate radiation exposure, reduce costs, and increase availability.

10. Hamann HA, Croyle RT, Venne VL, Baty BJ, Smith KR, References Botkin JR. Attitudes toward the genetic testing of children among adults in a Utah-based kindred tested for BRCA1 1. Levy M, Pirson Y, Simon P et al. Evaluation in patients with mutation. Am J Med Genet 2000; 92: 25–32 Alport syndrome of knowledge of the disease and attitudes 11. Statement of the American Society of Clinical Oncology. Genetic towards prenatal diagnosis. Clin Nephrol 1994; 42: 211–220 testing for cancer susceptibility. J Clin Oncol 1996; 14: 1730–1736 2. Levy M, Richard S. Attitudes of von Hippel–Lindau disease 12. Watson ML. Complications of polycystic kidney disease. Kidney patients towards presymptomatic genetic diagnosis in children Int 1997; 51: 353–365 and prenatal diagnosis. J Med Genet 2000; 37: 476–478 13. Dickenson DL. Can children and young people consent to be 3. Delaporte C. Ways of announcing a late-onset heritable, distested for adult onset genetic disorders? BMJ 1999; 318: abling disease and their psychological consequences. Genet Couns 1063–1066 1996; 7: 289–296 14. Hodgkinson KA, Kerzin-Storrar L, Watters EA, Harris R. 4. Harper PS. What do we mean by genetic testing? J Med Genet Adult polycystic kidney disease: knowledge, experience, and 1997; 34: 749–752 attitudes to prenatal diagnosis. J Med Genet 1990; 27: 552–558 5. McKinnon WC, Baty BJ, Bennet RL et al. Predisposition genetic 15. Sujansky E, Beeler Kreutzer S, Johnson AM, Lezotte DC, testing for late-onset disorders in adults. A position paper of Schrier RW, Gabow PA. Attitudes of at-risk and affected the National Society of Genetic counsellors. JAMA 1997; 278: individuals regarding presymptomatic testing for autosomal 1217–1220 dominant polycystic kidney disease. Am J Med Genet 1990; 6. Austad T. The right not to know—worthy of preservation any 35: 510–515 longer? An ethical perspective? Clin Genet 1996; 50: 85–88 16. Pajari H, Koskimies O, Muhonen T, Kaarianen H. The burden 7. Marsick R, Limwongse C, Kodish E. Genetic testing for renal of genetic disease and attitudes towards gene testing in Alport diseases: medical and ethical considerations. Am J Kidney Dis syndrome. Pediatr Nephrol 1999; 13: 471–476 1998; 32: 934–945 17. Korf BR. Genetic testing for patients with renal disease: proced8. Ravine D, Gibson RN, Walker RG, Sheffield LJ, Kincaidure, pitfalls, and ethical considerations. Semin Nephrol 1999; Smith P, Danks DM. Evaluation of ultrasonographic diagnostic 19: 319–326 criteria for autosomal dominant polycystic kidney disease 1. 18. Macnicol AM, Wright AF. Counselling and ethical consideraLancet 1994; 343: 824–827 tions in autosomal dominant polycystic kidney disease. In: 9. Nicolau C, Torra R, Badenas C et al. Autosomal dominant Watson ML, Torres VE, eds. Polycystic Kidney Disease, Oxford polycystic kidney disease types 1 and 2: assessment of US sensitivity for diagnosis. Radiology 1999; 213: 273–276 University Press, Oxford, 1996; 568–583

The development of echo-enhancing agents has significantly improved the detection of the movement of fluid within the urinary tract by ultrasonography (US). The purpose of our study was to compare ultrasound voiding cystography (USVC) for the detection of vesicoureteric reflux (VUR) in children with direct radionuclide voiding cystography (DRVC). Ninety-nine children, aged 1.1-12.3 years, with 198 potentially refluxing units, were investigated simultaneously by DRVC and USVC. The indications for cystography were urinary tract infection, follow-up of a previously detected VUR, and screening of siblings of children with VUR. During the investigation an echo-enhancing agent (Levovist) was administered intravesically through a catheter already in place for the DRVC. The movement of both agents, radiotracer and Levovist, was registered simultaneously by a computerized gamma camera and US, respectively. The results were analyzed with DRVC representing the reference diagnostic test. The overall sensitivity and specificity of USVC for the detection of VUR were 79% and 92%, respectively. USVC may represent a reliable diagnostic tool for the detection and follow-up of VUR in children.

Unfavorable course of minimal change nephrotic syndrome in children with intrauterine growth retardation.BackgroundIntrauterine growth retardation (IUGR) is associated with higher morbidity and mortality not only in perinatal life but also in later life. The purpose of our study was to determine whether IUGR has any effect on the course of minimal change nephrotic syndrome (MCNS) in children.MethodsForty children who were between 1 and 16years old at the onset of MCNS, who have been followed for at least three years and for whom we were able to obtain birth weights and gestational ages, were included. The diagnosis of MCNS was predicted on the basis of clinical and laboratory features, and in 11 children (27.5%) the diagnosis was confirmed by renal biopsy. IUGR was defined as birth weight below the tenth percentile for gestational age.ResultsFive children (12.5%) had signs of IUGR at birth. In children with IUGR, we observed a higher mean number of relapses (10.4 vs. 3.3, P < 0.001) and a higher incidence of steroid dependency (80% vs. 21%, P < 0.02) than in children without IUGR. Other differences between children with and those without IUGR included more frequent treatment with cytotoxic agents and cyclosporine, and a higher incidence of renal biopsy in children with IUGR.ConclusionOur study demonstrated an unfavorable course of MCNS in children with IUGR. IUGR could therefore enable early identification of those children who are at risk of becoming frequent relapsers and of developing steroid dependency. This, however, should be confirmed in a larger number of patients.

Background Native arteriovenous fistula is the best vascular access for chronic hemodialysis. Primary and long-term success depends, in part, on the state of arteries and veins at the time of the operation. The aim of our study was to investigate the effects of intermittent compression of upper arm veins on forearm vessels in patients with terminal renal disease. Methods The study group comprised 16 chronic hemodialysis patients who performed daily intermittent compression of the upper arm without vascular access by elastic band (Eschmarch). Ten chronic hemodialysis patients were included in the control group which performed no specific activity. Forearm measurements were obtained at the beginning of the study and 4 and 8 weeks later during the course of intermittent compression of the upper arm veins. The forearm circumference and maximal handgrip strength were measured. The artery parameters, including endothelium-dependent vasodilatation and forearm vein parameters, were obtained by ultrasonography measurements. Results The forearm circumference, maximal handgrip strength and artery parameters, including endothelium-dependent vasodilatation, remained unchanged. The basal venous diameters (2.29 mm ± 0.19 at the beginning, 2.46 mm ± 0.19 after 4 weeks and 2.53 mm ± 0.18 after 8 weeks) were significantly increased in the study group. The distensibility of veins was preserved in the study group. There were no significant changes in the control group. Conclusions Our study demonstrated that daily intermittent compression of the upper arm veins increases the forearm vein diameter and preserves the distensibility of veins in patients with end-stage renal failure.

Arylcycloalkanes are produced from ω-alkenyl benzylselenides on reaction with alkyllithiums or on Lewis acid mediated electrophilic cyclisation.

Eighty-five percent of UTI in children is caused by Escherichia coli (E. coli). Other gramnegative bacteria include Klebsiella, Proteus, Pseudomonas, Enterobacter, and Citrobacter. Gram-positive bacteria include Staphylococcus saprophyticus, Enterococcus, and, rarely, Staphylococcus aureus. Non-E. coli UTI is more often associated with urinary tract anomalies, younger age, and previous antibiotic treatment (4). Viruses and fungi are uncommon causes of UTI in children (5, 6).

Arylcycloalkanes are produced from ω-alkenyl benzylselenides on reaction with alkyllithiums or on Lewis acid mediated electrophilic cyclisation.

Objective This exploratory study examined the role that illness representations and personality play in the various adherence behaviors of adolescents diagnosed with essential hypertension. Methods The participants were 97 hypertensive adolescents. They completed self-report questionnaires pertaining to (1) demographic and medical data, (2) adherence, (3) illness representations, and (4) personality. Medical charts were also assessed. Results The hierarchical regression analyses indicated that: (1) conscientiousness, agreeableness, and perception of treatment effectiveness account for a significant amount of variance in general adherence; (2) perception of treatment effectiveness is predictive of overall specific adherence; and (3) for adherence to most of the individual specific regimen recommendations, illness representations are more predictive compared to personality dimensions. Conclusions The personality domains of conscientiousness, extraversion, agreeableness, and illness representation dimensions (treatment control, concern, and emotional burden) were shown to predict adherence behaviors in adolescent hypertensive patients differentially. Study implications and limitations are discussed.

Primary vesicoureteric reflux accounts for approximately 10% of kidney failure requiring dialysis or transplantation, and sibling studies suggest a large genetic component. Here, we report a whole-genome linkage and association scan in primary, nonsyndromic vesicoureteric reflux and reflux nephropathy. We used linkage and family-based association approaches to analyze 320 white families (661 affected individuals, generally from families with two affected siblings) from two populations (United Kingdom and Slovenian). We found modest evidence of linkage but no clear overlap with previous studies. We tested for but did not detect association with six candidate genes (AGTR2, HNF1B, PAX2, RET, ROBO2, and UPK3A). Family-based analysis detected associations with one single-nucleotide polymorphism (SNP) in the UK families, with three SNPs in the Slovenian families, and with three SNPs in the combined families. A case-control analysis detected associations with three additional SNPs. The results of this study, which is the largest to date investigating the genetics of reflux, suggest that major loci may not exist for this common renal tract malformation within European populations.

To determine the occurrence of primary nocturnal enuresis in 5-year-old outpatients in Slovenia and the possible correlations with different factors.The epidemiological study was conducted in Slovenia between 2005 and 2007. A special questionnaire was distributed randomly among the parents of 1846 5-year olds in children's outpatient clinics in all regions of Slovenia.The response rate was on average 71.0%, which means that 7% of all Slovenian 5-year olds were included in the study. The occurrence of primary nocturnal enuresis was 8.7% and was higher in families with many siblings (chi(2) test, p0.01). The boy:girl ratio was 1.4 (Student t-test, p = 0.024). Parents were found to be more disturbed by the problem than their children (chi(2) test, p0.01). The maternal and paternal education levels of children with primary nocturnal enuresis did not differ from the Slovenian adult population (chi(2) test, p0,05).The occurrence of primary nocturnal enuresis in 5-year-old outpatients in Slovenia is comparable with data from other countries. Primary nocturnal enuresis is more frequent in boys than in girls, with higher occurrence in families with more siblings, and parents are more disturbed by the problem than their children.

The purpose of our prospective study was to find out whether ureteric jet Doppler waveform (UJDW) could be a reliable predictor of vesicoureteral reflux (VUR) in children, compared with echo-enhanced voiding ultrasonography (VUS). Echo-enhanced VUS was performed in 75 children, 57 girls and 18 boys, aged 3 years to 12 years, following the accepted indications for this procedure. During the same procedure the measurement of UJDW was also performed and was considered to be successful (in 70 children) when at least ten UJDWs were recorded per ureteric unit. Depending on the shape of the UJDWs, the sequences were classified into three groups: monophasic, suggestive of VUR; complex, not suggestive of VUR; and mixed sequence, suggestive of VUR when a certain ratio between monophasic and complex UJDWs was achieved. When all three sequences were taken into account, the overall sensitivity and specificity of this method in detecting VUR were 88.5% and 82.3%, respectively. These values seem high enough for this method to be considered as a good alternative to invasive micturating cystographies in screening children for VUR.

The purpose of our study was to assess the influence of handgrip training and intermittent compression of the upper arm veins on forearm arteries and veins. Eighteen chronic hemodialysis patients performed daily handgrip training for 8 weeks using a rubber ring, together with daily intermittent compression of the upper arm veins by elastic band. The forearm circumference, maximal handgrip strength, and arterial and vein parameters, including endothelium-dependent vasodilatation, were measured at the beginning, and after 4 and 8 weeks (using ultrasound scanning). The maximal handgrip strength and forearm circumference increased significantly. The radial artery diameters were significantly higher after 8 weeks of training (1.89 mm +/- 0.10 at the beginning, 1.95 +/- 0.10 mm after 8 weeks, P = 0.007), and endothelium-dependent vasodilatation was also found to be increased after 4 and 8 weeks of both activities. The venous parameters before tourniquet placement increased significantly after 8 weeks (2.40 +/- 0.16 mm at the beginning, 2.62 +/- 0.17 mm after 8 weeks, P = 0.014), and the venous parameters after tourniquet placement increased significantly after 4 and 8 weeks (3.36 +/- 0.17 mm at the beginning, 3.51 +/- 0.18 mm after 4 weeks, P = 0.009), 3.68 +/- 0.18 mm after 8 weeks, P < 0.001). The distensibility of veins was preserved. Our results showed that handgrip training and intermittent compression of the upper arm veins, performed daily, increase the diameter of forearm arteries and veins and improve endothelium-dependent vasodilatation.

The purpose of our prospective study was to determine the value of indirect voiding urosonography without the use of contrast-media and without filling of the bladder through a catheter (IVUS) for detection of vesicoureteral reflux (VUR) in children, compared with echo-enhanced voiding urosonography (VUS). Among 57 children (45 girls and 12 boys, aged 2.7 to 12.0 years) admitted for echo-enhanced VUS either as part of routine evaluation after urinary tract infection (UTI) or follow-up of a previously detected VUR, IVUS was also successfully performed in 47 children. The results were considered positive when there was any increase in pelvis size and/or ureter lumen width during voiding. The overall sensitivity of IVUS in the detection of VUR was 49%, specificity 75%. The most accurate results were obtained with VUR grade III, where IVUS correctly detected 6 out of 7 cases, a sensitivity of 86%. The average increase of AP pelvis diameter during voiding was highly significant only in uretero-renal units with VUR grade III. Considering the obstacles in conducting the investigation and its relatively low overall sensitivity and specificity, it seems that IVUS is not sufficiently reliable to replace echo-enhanced VUS.

Real-time ultrasound-guided renal biopsy (RB) with a biopsy gun has become a standard procedure in the treatment of children. The purpose of the study was to establish the complication rate after real-time ultrasound-guided RB with a biopsy gun, the adequacy of renal tissue samples for pathohistological tests, the rate of concurrence between clinical and pathohistological diagnoses, and the benefits of the procedure. From January 1994 to October 1999, 88 renal biopsies were performed on 82 children, 81 of whom (35M, 46F, aged 3-20 y) were included in this retrospective study. The nephrotic syndrome (in infants, older children, those with evidence of nephritis or failing corticosteroid therapy) was the most frequent indication of RB. Other indications were non-nephrotic proteinuria, nephritic syndrome, glomerular haematuria, renal allograft dysfunction, unexplained acute or chronic renal failure, and kidney disease progression monitoring. No serious complications were noted. The adequacy rate of renal tissue samples ranged from 93.1 to 96.6%, depending on which definition of the adequacy of renal tissue samples was used. Clinical and pathohistological diagnoses matched in 81.4% of the cases. Data obtained by RB were very beneficial to patients in terms of establishing, confirming or altering the diagnosis and, consequently, the treatment.The results confirm that real-time ultrasound-guided RB with a biopsy gun is a safe procedure and provides information that is very beneficial to patients.

The influence of dialyzer membrane on the morbidity and mortality of patients with acute renal failure remains a matter of debate. The aim of the prospective randomized clinical study was to assess the influence of the flux of a synthetic dialyzer membrane on patients' survival rate, restitution of renal function, and duration of hemodialysis treatment of patients with acute renal failure as a part of multiorgan failure. Seventy-two patients treated in intensive care units of the University Medical Center Ljubljana were randomized according to the dialyzer used throughout the duration of hemodialysis treatment. There were 38 patients in the low-flux group (dialyzer F6, low-flux polysuphone, Fresenius, Bad Homburg, Germany) and 34 patients in the high-flux group (dialyzer Filtral 12, sulphonated high-flux polyacrylonitrile, Hospal, Industrie Meyzieu, France). Both groups were balanced in terms of sex, age, APACHE II score, oliguria before dialysis, cause of acute renal failure, inotropic support, mechanical ventilation, and the number of failing organs. The patients' survival rate was 18.7% in the low-flux group and 20.6% in the high-flux group. Ten patients (26.3%) recovered their renal function in the low-flux group and 8 (23.5%) in the high-flux group. Hemodialysis treatment lasted 11.2 days in the low-flux and 10.7 days in the high-flux group. An analysis of subgroups with a lower mortality rate (subgroup of patients without oliguria and subgroup of patients with less than 4 failed organ systems) did not show significant differences between the low-flux and high-flux groups in terms of survival rate, recovery of renal function, and duration of hemodialysis treatment. In conclusion, no significant differences were found in the results of low-flux versus high-flux synthetic membrane dialyzer treatment in patients with acute renal failure as a part of multiorgan failure in terms of survival rate, recovery of renal function, incidence of oliguria during hemodialysis, and duration of hemodialysis treatment. The number of failing organs seems to be the most important single factor determining the survival of patients with acute renal failure as a part of multiorgan failure.

Background. The clinical significance of vesicoureteric reflux (VUR) in renal transplant recipients remains controversial. Voiding urosonography (VUS), a new modality for detecting VUR, can be used in these patients. The sensitivity of X-ray and radionuclide cystography for detecting VUR may be improved with cyclic procedures. The aim of our study was to evaluate whether cyclic VUS is superior to the single-cycle procedure. Methods. Cyclic VUS was performed in 27 renal transplant recipients. Eight were children or adolescents and the remaining 19 recipients were adults. VUS was performed according to accepted guidelines. After the first micturition, the catheter was left in place and the entire procedure was repeated under the same conditions. Results. Both initial cycle and cyclic VUS detected 17 out of 27 (63%) VURs in the same patients. The sensitivity was not improved by cyclic VUS. However, there were differences between the initial cycle and cyclic VUS (P = 0.028) when comparing the number of negative results and the grades of VURs detected. This difference was even more pronounced when analysing only positive results. In the initial cycle, five out of 17 (29%) VURs were grade III, compared with 10 out of 17 (59%) grade III VURs in the same patients using the cyclic procedure (P = 0.008). Conclusions. Cyclic VUS did not improve the detection sensitivity for VUR in our study. However, given that VUR grade may be important for the management of renal transplant recipients, the use of cyclic VUS may provide a useful diagnostic tool for these patients.

The purpose of the study was to determine the incidence of vesicoureteric reflux (VUR), renal scars and hypertension in asymptomatic siblings of children with VUR. The study comprised 105 siblings of patients with VUR. Their age ranged from 4 months to 6.3 years. All had a direct radionuclide voiding cystography (DRVC) performed, and VUR was detected in 47 of 105 (45%). High grade VUR in the first year of life had an incidence of 50% compared with a 9% incidence in siblings older than 2 years, while only one of the 27 siblings with a low VUR grade was younger than 1 year. In 43 of 47 siblings with VUR, a technetium-99m dimercaptosuccinic acid (99mTc-DMSA) scan was performed and renal scars were found in 10, which presents 23% of siblings with VUR who were scanned and 10% of all siblings studied. One child had hypertension. Identifying VUR among asymptomatic siblings could possibly prevent renal damage and its consequences. Thus, the predictive value of positive family history alone in identifying VUR was 45% while 23% of siblings had renal scars. This incidence justifies the routine investigation of asymptomatic siblings, by using DRVC at an early stage.

Urogenital infection with Chlamydia trachomatis in adults and adolescents is a common sexually transmitted disease. The purpose of this study was to investigate whether isolated microhematuria in children and adolescents is associated with Chlamydia trachomatis infection of the urinary tract. The study group included 37 children and adolescents with isolated nonglomerular microhematuria. Urethral smears for the isolation of Chlamydia trachomatis in cell culture were taken at the time of cystourethroscopy from all patients. Polymerase chain reaction (PCR) for the detection of chlamydial DNA in urine was carried out in 25 of 37 (68%) patients and direct immunofluorescence (DIF) of urine in 16 of 37 (43%) patients. The control group included 33 children and adolescents without hematuria; PCR and DIF of urine were carried out in all controls. Chlamydia trachomatis infection of the urinary tract was confirmed in 8 of 37 (22%) patients in the study group, and in none in the control group (0 of 33, P

Intrauterine growth retardation (IUGR) resulting in a reduced number of nephrons is one of the nonimmune mechanisms that have been recently proposed as contributing to the progression of renal diseases. The purpose of our study was to determine whether IUGR has any effect on the clinical course and prognosis of IgA glomerulonephritis (IgA GN) in children. Fifty children with biopsy-proven IgA GN, who were followed for at least 3 years, were included. Six of the 50 children (12%) had signs of IUGR at birth, defined as birth weight below the 10th percentile for gestational age. There were no significant differences in initial clinical presentation between children with IUGR and those without IUGR. However, in kidney biopsy specimens, we found a significantly higher mean percentage of sclerotic glomeruli in children with IUGR than in those without IUGR (33 vs. 13%, p < 0.015). At the end of the follow-up period, we observed a significantly higher incidence of arterial hypertension in children with IUGR than in those without IUGR (50 vs. 11%, p < 0.05). Other differences between the two groups of children were not statistically significant. In conclusion, our study demonstrated an increased risk of the development of arterial hypertension and glomerulosclerosis in children with IgA GN who had suffered from IUGR with a birth weight below the 10th percentile for gestational age. IUGR may therefore help to identify early in the course of IgA GN those children who are at higher risk of an unfavorable course.

The aim of the study was to evaluate the development of renal scarring, vesicoureteric reflux (VUR) and kidney growth in asymptomatic children with VUR during 3–7 years. The results of the study indicate that routine screening for VUR of asymptomatic siblings of children with VUR and other asymptomatic populations at risk is recommended, since high grade sterile VUR seems to be an important factor in development of renal scarring.