Sphingosine phosphate lyase insufficiency syndrome: a systematic review.

BACKGROUND: Sphingosine-1-phosphate lyase insufficiency syndrome (SPLIS) or nephrotic syndrome type-14 is caused by biallelic mutations in SGPL1. Here, we conducted a systematic review to delineate the characteristics of SPLIS patients. METHODS: A literature search was performed in PubMed, Web of Science, and Scopus databases, and eligible studies were included. For all patients, demographic, clinical, laboratory, and molecular data were collected and analyzed. RESULTS: Fifty-five SPLIS patients (54.9% male, 45.1% female) were identified in 19 articles. Parental consanguinity and positive family history were reported in 70.9% and 52.7% of patients, respectively. Most patients (54.9%) primarily manifested within the first year of life, nearly half of whom survived, while all patients with a prenatal diagnosis of SPLIS (27.5%) died at a median [interquartile (IQR)] age of 2 (1.4-5.3) months (P = 0.003). The most prevalent clinical feature was endocrinopathies, including primary adrenal insufficiency (PAI) (71.2%) and hypothyroidism (32.7%). Kidney disorders (42, 80.8%) were mainly in the form of steroid-resistant nephrotic syndrome (SRNS) and progressed to end-stage kidney disease (ESKD) in 19 (36.5%) patients at a median (IQR) age of 6 (1.4-42.6) months. Among 30 different mutations in SGPL1, the most common was c.665G > A (p.Arg222Gln) in 11 (20%) patients. Twenty-six (49.1%) patients with available outcome were deceased at a median (IQR) age of 5 (1.5-30.5) months, mostly following ESKD (23%) or sepsis/septic shock (23%). CONCLUSION: In patients with PAI and/or SRNS, SGPL1 should be added to diagnostic genetic panels, which can provide an earlier diagnosis of SPLIS and prevention of ESKD and other life-threatening complications.

Clinical Outcomes of 141 Cases of Isolated Antenatal Hydronephrosis; An Observational Study.

INTRODUCTION: Hydronephrosis, a condition that is mostly congenital, is considered as the most common type of pediatric urinary tract disorder. The aim of this study was the evaluation of the prognosis and outcomes of hydronephrosis in cases of congenital hydronephrosis. METHODS: In a cross-sectional study, run in a tertiary clinic of pediatric nephrology, from 2015 to 2020, patients with fetal hydronephrosis were selected. Ultrasonography, urinalysis and kidney function tests were ordered for all patients and in the presence of hydronephrosis, repeated ultrasonography, voiding cystourethrography and dimercaptosuccinic acid scan were performed. In cases with evidence of obstruction, a diethylenetriamine pentaacetic acid scan and relative surgical procedures were performed. RESULTS: Among 141 cases, mean age was 8 ± 1.4 years and 80.9% were male. Partial or complete obstruction in the right and left kidney was found in 16.3 and 24.8% of patients, respectively. The degree of hydronephrosis was mild in 46.1%, moderate in 39%, and severe in 9.2% of the patients. At the last follow-up period, hydronephrosis recovered in 46% of the patients, while 54% experienced persistence or exacerbation of the disease. Meanwhile, 7.1% of patients showed neurogenic bladder, 19.1% urinary tract infection and 22.7% urinary stones. CONCLUSION: Our study revealed that fetal hydronephrosis ends in complete recovery following birth in 46% of the cases. However, in cases experiencing persistent or exacerbating hydronephrosis, optimized treatment and/or surgical intervention are required.  DOI: 10.52547/ijkd.6516.

Low defect and high electrical conductivity of graphene through plasma graphene healing treatment monitored with in situ optical emission spectroscopy.

Fundamental studies on graphene (Gr) and its real device applications have been affected by unavoidable defects and impurities which are usually present in synthesized Gr. Therefore, post treatment methods on Gr have been an important subject of research followed by the community. Here, we demonstrate a post-treatment of cm-sized CVD-grown graphene in a Radio Frequency-generated low-pressure plasma of methane and hydrogen to remove oxygen functional groups and heal the structural defects. The optimum plasma treatment parameters, such as pressure, plasma power, and the ratio of the gases, are optimized using in-situ optical emission spectroscopy. This way we present an optimal healing condition monitored with in situ OES. A twofold increase in the conductivity of plasma-treated Gr samples was obtained. Plasma treatment conditions give insights into the possible underlying mechanisms, and the method presents an effective way to obtain improved Gr quality.

Dynamic tuning of photon-plasmon interaction based on three-dimensionally confined microtube cavities.

We present tunable coupling between surface plasmon resonances supported by a metal-nanoparticle-coated tip and three-dimensionally (3D) confined optical modes supported by a microtube cavity. The competition and transition between two types of coupling mechanisms, i.e., dielectric-dielectric and plasmon-dielectric coupling, are observed in the tunable system. Owing to the competition between the two coupling mechanisms, the resonant modes can be dynamically tuned to first shift from higher to lower energies and then revert to higher energy. Moreover, the unique spatial field distribution of 3D confined modes allows selective coupling of odd and even order axial modes with surface plasmon resonances.

Chronic Kidney Disease in Iran: First Report of the National Registry in Children and Adolescences.

PURPOSE: Knowing the epidemiological aspects of chronic kidney disease (CKD) in children is crucial for early recognition, identification of reversible causes, and prognosis. Here, we report the epidemiological characteristics of childhood CKD in Iran. MATERIALS AND METHODS: This cross-sectional study was conducted during 1991 - 2009. The data were collected using the information in the Iranian Pediatric Registry of Chronic Kidney Disease (IPRCKD) core dataset. RESULTS: A total of 1247 children were registered. The mean age of the children at registration was 0.69 ± 4.72 years (range, 0.25 -18 years), 7.79 ± 3.18 years for hemodialysis (HD), 4.24 ± 1.86 years for continuous ambulatory peritoneal dialysis (CAPD), and 3.4±1.95 years for the children who underwent the renal transplantation (RT) (P < .001). The mean year of follow-up was 7.19 ± 4.65 years. The mean annual incidence of CKD 2-5 stages was 3.34 per million age-related population (pmarp). The mean prevalence of CKD 2-5 stages was 21.95 (pmarp). The cumulative 1-, 5-, and 10-year patients' survival rates were 98.3%, 90.7%, and 84.8%, respectively. The etiology of the CKD included the congenital anomalies of the kidney and urinary tract (CAKUT) (40.01%), glomerulopathy (19.00%), unknown cause (18.28%), and cystic/hereditary/congenital disease (11.14%). CONCLUSION: The incidence and prevalence rate of pediatric CKD in Iran is relatively lower than those reported in Europe and other similar studies. CAKUT was the main cause of the CKD. Appropriate management of CAKUT including early urological intervention is required to preserve the renal function. Herein, the long-term survival rate was higher among the children with CKD than the literature.

Multiplexing and tuning of a double set of resonant modes in optical microtube cavities monolithically integrated on a photonic chip.

In this Letter, we experimentally demonstrate a monolithic integration of two vertically rolled-up microtube resonators (VRUMs) on polymer-based 1×5 multimode interference waveguides to achieve 3D multi-channel coupling. In this configuration, different sets of resonant modes are simultaneously excited at S-, C-, and L- telecom bands, demonstrating an on-chip multiplexing, based on a vertical-coupling configuration. Moreover, the resonant wavelength tuning and consequently the overlapping of resonant modes are accomplished via covering the integrated VRUMs by liquid. A maximum sensitivity of 330 nm/refractive index unit is achieved. The present work would be a critical step for the realization of massively parallel optofluidic sensors with higher sensitivity and flexibility for signal processing, particularly in a 3D-integrated photonic chip.

Optical microtube cavities monolithically integrated on photonic chips for optofluidic sensing.

Microtubular optical resonators are monolithically integrated on photonic chips to demonstrate optofluidic functionality. Due to the compact subwavelength-thin tube wall and a well-defined nanogap between polymer photonic waveguides and the microtube, excellent optical coupling with extinction ratios up to 32 dB are observed in the telecommunication relevant wavelength range. For the first time, optofluidic applications of fully on-chip integrated microtubular systems are investigated both by filling the core of the microtube and by the microtube being covered by a liquid droplet. Total shifts over the full free spectral range are observed in response to the presence of the liquid medium in the vicinity of the microtube resonators. This work provides a vertical coupling scheme for optofluidic applications in monolithically integrated so-called "lab-in-a-tube" systems.

Luminescent nanoparticles embedded in TiO2 microtube cavities for the activation of whispering-gallery-modes extending from the visible to the near infrared.

Luminescent nanoparticles (NPs) are deposited onto two dimensional (2D) pre-strained TiO2 nanomembranes by spin-coating. After rolling up the 2D differentially strained TiO2 nanomembranes into 3D microtube structures, the NPs are embedded within the tube windings. The embedded NPs serve as a light source for optical whispering-gallery-mode resonances under laser excitation, and therefore allow the TiO2 microtube to work as an active microcavity operating in emission mode. The spectral range of resonant modes can be tuned from the visible to the near infrared by embedding the proper NPs in the TiO2 tube wall. Rolled-up TiO2 microcavities combined with luminescent NPs could offer interesting opportunities in a variety of research fields, such as bio- and nanophotonics, optoelectronics, and optofluidics.

The Influence of Cu+2 Concentration on the Magnetic Properties and Microstructure of Pulse Electrodeposited Co(x)Cu(1-x), Nanowire Arrays.

Ordered Co(x)Cu(1-x) nanowire arrays were fabricated by alternating current pulse electrodeposition using anodized aluminum oxide templates. The effect of the Cu+2 concentration on the composition, magnetic properties and microstructure has been investigated. It was found that the coercivity and squareness of the as-deposited Co(x)Cu(1-x) nanowires decreased by increasing the Cu composition. Significant differences in crystal structures indicate a strong dependence of the crystal structure of Co(x)Cu(1-x) nanowires on the Cu composition.

Vertical optical ring resonators fully integrated with nanophotonic waveguides on silicon-on-insulator substrates.

We demonstrate full integration of vertical optical ring resonators with silicon nanophotonic waveguides on silicon-on-insulator substrates to accomplish a significant step toward 3D photonic integration. The on-chip integration is realized by rolling up 2D differentially strained TiO(2) nanomembranes into 3D microtube cavities on a nanophotonic microchip. The integration configuration allows for out-of-plane optical coupling between the in-plane nanowaveguides and the vertical microtube cavities as a compact and mechanically stable optical unit, which could enable refined vertical light transfer in 3D stacks of multiple photonic layers. In this vertical transmission scheme, resonant filtering of optical signals at telecommunication wavelengths is demonstrated based on subwavelength thick-walled microcavities. Moreover, an array of microtube cavities is prepared, and each microtube cavity is integrated with multiple waveguides, which opens up interesting perspectives toward parallel and multi-routing through a single-cavity device as well as high-throughput optofluidic sensing schemes.

Relationship of generalized joint hypermobility with vesicoureteral reflux and urinary tract infection.

INTRODUCTION: Generalized joint hypermobility is deemed to be an underlying risk factor for many clinical conditions. The goal of this study was to determine the prevalence of generalized joint hypermobility in patients with vesicoureteral reflux. MATERIALS AND METHODS: This was a cross-sectional study on 313 children, 3 to 15 years old, with a history of urinary tract infection. Generalized joint hypermobility was evaluated according to the Beighton scores. Urinary tract ultrasonography and cystography were done if indicated. Participants were divided into 2 groups, group 1 without urinary tract abnormality and group 2 with primary vesicoureteral reflux, which were compared with the control group. RESULTS: Generalized joint hypermobility was documented in 37.2% of the children in the control group and 45.7% of those in group 1. This rate was 62.3% in group 2 (odds ratio, 2.79; 95% confidence interval, 1.61 to 4.82). Generalized joint hypermobility was seen in 44.1% of the children with mild vesicoureteral reflux, 60.5% of those with moderate vesicoureteral reflux, and 86.2% of those with severe vesicoureteral reflux. There was a significant relationship between the hypermobility incidence and the urinary reflux severity (P = .003). CONCLUSIONS: This study showed the prevalence of generalized joint hypermobility in children with vesicoureteral reflux was more than that in the general population, and the prevalence of hypermobility syndrome increased with the reflux severity.

Rolled-up TiO2 optical microcavities for telecom and visible photonics.

The fabrication of high-quality-factor polycrystalline TiO2 vertically rolled-up microcavities (VRUMs) by the controlled release of differentially strained TiO2 bilayered nanomembranes, operating at both telecom and visible wavelengths, is reported. Optical characterization of these resonators reveals quality factors as high as 3.8×10³ in the telecom wavelength range (1520-1570 nm) by interfacing a TiO2 VRUMs with a tapered optical fiber. In addition, a splitting in the fundamental modes is experimentally observed due to the broken rotational symmetry in our resonators. This mode splitting indicates coupling between clockwise and counterclockwise traveling whispering gallery modes of the VRUMs. Moreover, we show that our biocompatible rolled-up TiO2 resonators function at several positions along the tube, making them promising candidates for multiplexing and biosensing applications.

Early detection of acute kidney injury by serum cystatin C in critically ill children.

BACKGROUND: We prospectively evaluated whether serum cystatin C (CysC) detected acute kidney injury (AKI) earlier than basal serum creatinine (Cr). METHODS: In 107 pediatric patients at high risk of developing AKI, serum Cr and serum CysC were measured upon admission. Baseline estimated creatinine clearance (eCCl) was calculated using a CysC-based glomerular filtration rate (GFR) equation from a serum Cr measured at the pediatric intensive care unit (PICU) entrance. RESULTS: The median age was 10 months (interquartile range, 3-36 months). Serum Cr, serum CysC, and eCCl (mean ± standard deviation [range]) were 0.5 ± 0.18 mg/dl (0.2-1.1 mg/dl), 0.53 ± 0.78 (0.01-3.7 mg/l), and 72.55 ± 28.72 (20.6-176.2) ml/min per 1.73 m(2), respectively. The serum CysC level in patients with AKI was significantly higher than children with normal renal function (p < 0.001). The values for the cut-off point, sensitivity, specificity, and the area under curve (AUC) were determined for CysC as 0.6 mg/l, 73.9 %, 78.9 %, and 0.92 [95 % confidence interval (0.82-1)], respectively, and for Cr the values were 0.4 mg/dl, 68 %, 46.2 %, and 0.39, [95 % confidence interval (0.24-0.54)], respectively. The receiver operating characteristics (ROC) curve analysis revealed that CysC had a significantly higher diagnostic accuracy than eCCl (p < 0.001). CONCLUSIONS: Our results identify that the sensitivity of serum CysC for detecting AKI is higher than that of serum Cr in a heterogeneous pediatric intensive care unit (PICU) population.

Photoactive rolled-up TiO2 microtubes: fabrication, characterization and applications†Electronic supplementary information (ESI) available. See DOI: 10.1039/c4tc00796dClick here for additional data file.

Because of its unique properties, titania (TiO2) represents a promising candidate in a wide variety of research fields. In this paper, some of the properties and potential applications of titania within rolled-up nanotechnology are explored. It is shown how the structural and optical properties of rolled titania microtubes can be controlled by properly tuning the microfabrication parameters. The rolling up of titania films on different sacrificial layers and containing different shapes, achieving a control on the diameter of the fabricated titania microtubes, is presented. In order to obtain the more photoactive crystalline form of titania, one during-fabrication and two post-fabrication methods are demonstrated. Interesting applications in the fields of photocatalysis and photonics are suggested: the use of titania rolled-up microtubes as micromotors and optical microresonators is presented.

Histopathologic and clinical findings of congenital nephrotic syndrome in Iranian children: a study of two centers.

INTRODUCTION: Congenital nephrotic syndrome (CNS), an uncommon form of kidney disease, presents during the first year of life and is a diagnostic and therapeutic challenge for the pediatricians as well as pediatric nephrologists. Our study is the first study of Iranian children with CNS in two pediatric nephrology centers in Tehran, Iran. MATERIALS AND METHODS: We reviewed medical charts of 30 infants diagnosed with CNS from 1990 to 2005. RESULTS: There were 15 boys and 15 girls with CNS (mean age, 1.7 months). The presentation of the disease was nephrotic syndrome in 96.6% of the patients. Eighty percent of the patients presented within 3 months of life and 16 in the neonatal period. The Finnish type of CNS was seen in 43.3% and diffuse mesangial sclerosis in 50%. Preterm labor and low birth weight was seen in 20%. A family history of nephrotic syndrome in infancy was noted for 8 children (26.7%). Numerous complications of nephrotic syndrome occurred in 73.3%. Seventy percent of the patients had 27 episodes of infections. Sepsis was seen in 43.3% of the children, of which 61.5% were caused by gram-negative bacteria and 38.6% were caused by Staphylococcus aureus. Thrombotic complications and hypertension developed in 6.6% and 23.3% of the patients, respectively. The mortality rate of patients was 86.6%. CONCLUSIONS: Diffuse mesangial sclerosis is an important cause of CNS. The outcome of our patients was poor and most of our patients died before reaching the age of 5 years old.

Urinary calcium and uric acid excretion in children with vesicoureteral reflux.

Urolithiasis is relatively common in children, and identifiable predisposing factors for stone formation, including metabolic and structural derangements, can be established in most cases. Vesicoureteral reflux (VUR) is a common cause of kidney stone formation. The pathophysiological mechanism of urolithiasis in reflux is related to urinary tract infection and urinary stasis, both of which promote urinary crystal formation, but metabolic causes, such as crystallurias (mostly hypercalciuria), may also be involved in this process. However, few studies on urinary calcium and uric acid excretion in children with VUR have been conducted. We have studied the frequency of hypercalciuria and hyperuricosuria in children with VUR and compared the results with those from a control group. The VUR group comprised 108 children with VUR (19 boys, 89 girls; age range 3 months to 12 years), and the control group comprised 110 healthy children without any history of reflux or urinary tract infection (30 boys, 80 girls; age range 2 months to 12 years). Fasting urine was analyzed for the calcium/creatinine (Ca/Cr) and uric acid/creatinine (UA/Cr) ratios. Hypercalciuria was more frequently diagnosed in the VUR patients than in the control group (21.3 vs. 3.6%; P = 0.0001). Significant differences between the two groups were also found for the mean Ca/Cr and UA/Cr ratios (P = 0.0001 and P = 0.0001, respectively). No differences were found in the urinary Ca/Cr or UA/Cr ratios related to VUR grading or unilateral/bilateral VUR in the patient group, with the exception of those for hypercalciuria and mild VUR (P = 0.03). The association of urinary stones and microlithiasis in the VUR group was 29.6%. Our results demonstrate that the frequency of hypercalciuria and hyperuricosuria was higher in pediatric patients with VUR than in healthy children. Knowing this relationship, preventive and therapeutic interventions for stone formation in VUR could be greatly expanded.

Clinical course and outcome of children with steroid-sensitive nephrotic syndrome.

We conducted a retrospective study on children with primary nephrotic syndrome (NS) to evaluate the clinical course and outcome of children with steroid-sensitive NS (SSNS). The medical records of 226 children, median 3.46 years (min 1.00, max 15.08) who referred to our clinics with SSNS between January 1978 and September 2005 were reviewed and entered into the study. Minimum duration of follow-up was 5 years and maximum 20 years (median 7.25 years). Of 226 patients who were treated with corticosteroids, 38 (16.8%) had no relapse but the remaining 188 (83.2%) patients experienced several relapses of which 128 patients (56.6%) required additional immunosuppressive agents for the remission. Of these, 122 (95%) were treated with levamisole, 22 (17%) with cyclosporine, 36 (28%) with cyclophosphamide, and ten (7.8 %) treated with mycophenolate mofetil. Several patients had to switch from one medication to others due to lack of response. On the last follow-up visit, 64(28.3%) patients were still under treatment, some patients had taken all of the above-mentioned drugs but still had multiple recurrences. Only 103 (45.5%) patients were in remission off the drug more than 3 years. This study shows that nearly one-third of pediatric patients with SSNS experience frequent relapses despite the combination of multiple immunosuppressive medications, which may continue until adulthood.

The Effect of Long-term Steroid Therapy on Linear Growth of Nephrotic Children.

OBJECTIVE: Steroids are still the mainstay of management of nephrotic syndrome (NS). It was shown that steroids could impair growth and development of children. However, other clinical studies have shown conflicting results. METHODS: Hospital records of 147 children with diagnosis of NS who were followed during 1988-2008 are reviewed relating to height measurements. All patients were treated with prednisolone and had been followed for at least five years. Height measures were transformed into standard deviation score (SDS). Information on dose and duration of prednisolone therapy, histological findings of biopsy as well as concomitant use of steroid-sparing agents (SSA) were also analyzed. FINDINGS: Mean age at onset of NS was 5.94 years and at last follow-up visit 15.08 years. All patients had normal renal function during entire duration of the study. Analysis of the whole population did not show any significant alterations in the height SDS (Ht(SDS)) between the first and the last follow-up visit (P=0.5; -0.76±2.0 vs. -0.89±2.05 respectively). The patients were divided into two subgroups. Subgroup A, which achieved growth improvement, was composed of 62 children (initial Ht(SDS) -1.63; final Ht(SDS) -0.08; P<0.001) and subgroup B, that showed growth retardation, included 85 children (initial Ht(SDS) -0.13; final Ht(SDS) -1.59; P<0.001). CONCLUSION: No statistically significant retardation of linear growth was observed in the study population as a group following treatment with prednisolone according to the guidelines of ISKDC. Although about 62 subjects had growth retardation, children treated with prednisolone were not different from those who had increased growth.