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1.
World J Pediatr ; 19(5): 425-437, 2023 May.
Article in English | MEDLINE | ID: mdl-36371483

ABSTRACT

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.


Subject(s)
Kidney Failure, Chronic , Lyases , Nephrotic Syndrome , Humans , Male , Female , Infant , Sphingosine , Nephrotic Syndrome/diagnosis , Nephrotic Syndrome/epidemiology , Nephrotic Syndrome/genetics , Mutation , Phosphates , Lyases/genetics
2.
Iran J Kidney Dis ; 16(5): 292-297, 2022 09.
Article in English | MEDLINE | ID: mdl-36178863

ABSTRACT

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.


Subject(s)
Hydronephrosis , Urinary Tract Infections , Child , Cross-Sectional Studies , Female , Humans , Hydronephrosis/diagnostic imaging , Hydronephrosis/etiology , Male , Pentetic Acid , Pregnancy , Succimer , Ultrasonography, Prenatal/methods
3.
Sci Rep ; 11(1): 20334, 2021 Oct 13.
Article in English | MEDLINE | ID: mdl-34645871

ABSTRACT

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.

4.
Opt Lett ; 45(20): 5720-5723, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-33057267

ABSTRACT

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.

5.
Urol J ; 18(1): 122-130, 2020 Sep 13.
Article in English | MEDLINE | ID: mdl-32920816

ABSTRACT

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.


Subject(s)
Renal Insufficiency, Chronic/epidemiology , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Humans , Incidence , Infant , Iran/epidemiology , Prevalence , Registries
6.
Opt Lett ; 43(19): 4703-4706, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30272719

ABSTRACT

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.

7.
Opt Lett ; 42(3): 486-489, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-28146508

ABSTRACT

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.

8.
Nanoscale ; 8(18): 9498-503, 2016 May 05.
Article in English | MEDLINE | ID: mdl-27102146

ABSTRACT

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.

9.
J Nanosci Nanotechnol ; 15(9): 6699-703, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26716231

ABSTRACT

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.

10.
Opt Lett ; 40(16): 3826-9, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-26274670

ABSTRACT

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.

11.
Iran J Kidney Dis ; 8(3): 189-93, 2014 May.
Article in English | MEDLINE | ID: mdl-24878940

ABSTRACT

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.


Subject(s)
Joint Instability/complications , Urinary Tract Infections/etiology , Vesico-Ureteral Reflux/etiology , Adolescent , Case-Control Studies , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Male
12.
Opt Lett ; 39(2): 189-92, 2014 Jan 15.
Article in English | MEDLINE | ID: mdl-24562103

ABSTRACT

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.

13.
Pediatr Nephrol ; 29(1): 133-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23989306

ABSTRACT

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.


Subject(s)
Acute Kidney Injury/blood , Acute Kidney Injury/diagnosis , Biomarkers/blood , Cystatin C/blood , Area Under Curve , Child, Preschool , Creatine/blood , Critical Illness , Early Diagnosis , Humans , Infant , ROC Curve
14.
J Mater Chem C Mater ; 2(29): 5892-5901, 2014 Aug 07.
Article in English | MEDLINE | ID: mdl-25580249

ABSTRACT

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.

17.
Iran J Kidney Dis ; 6(6): 426-31, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23146979

ABSTRACT

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.


Subject(s)
Kidney/pathology , Nephrotic Syndrome/congenital , Biopsy , Edema/etiology , Female , Follow-Up Studies , Humans , Hypertension/etiology , Infant , Iran/epidemiology , Male , Nephrotic Syndrome/complications , Nephrotic Syndrome/mortality , Thrombosis/etiology
20.
Pediatr Nephrol ; 27(1): 95-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21814729

ABSTRACT

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.


Subject(s)
Calcium/urine , Hypercalciuria/urine , Uric Acid/urine , Vesico-Ureteral Reflux/urine , Analysis of Variance , Biomarkers/urine , Case-Control Studies , Chi-Square Distribution , Child , Child, Preschool , Creatinine/urine , Cross-Sectional Studies , Female , Humans , Hypercalciuria/epidemiology , Infant , Iran/epidemiology , Logistic Models , Male , Odds Ratio , Risk Assessment , Risk Factors , Urolithiasis/epidemiology , Urolithiasis/urine , Vesico-Ureteral Reflux/epidemiology
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