26 research outputs found

    CDH12 as a Candidate Gene for Kidney Injury in Posterior Urethral Valve Cases:A Genome-wide Association Study Among Patients with Obstructive Uropathies

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    Background: Posterior urethral valves (PUVs) and ureteropelvic junction obstruction (UPJO) are congenital obstructive uropathies that may impair kidney development. Objective: To identify genetic variants associated with kidney injury in patients with obstructive uropathy. Design, setting, and participants: We included 487 patients born in 1981 or later who underwent pyeloplasty or valve resection before 18 yr of age in the discovery phase, 102 PUV patients in a first replication phase, and 102 in a second replication phase

    Improving the cell distribution in collagen-coated poly-caprolactone knittings

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    Contains fulltext : 108282.pdf (publisher's version ) (Open Access)Adequate cellular in-growth into biomaterials is one of the fundamental requirements of scaffolds used in regenerative medicine. Type I collagen is the most commonly used material for soft tissue engineering, because it is nonimmunogenic and a highly porous network for cellular support can be produced. However, in general, adequate cell in-growth and cell seeding has been suboptimal. In this study we prepared collagen scaffolds of different collagen densities and investigated the cellular distribution. We also prepared a hybrid polymer-collagen scaffold to achieve an optimal cellular distribution as well as sufficient mechanical strength. Collagen scaffolds [ranging from 0.3% to 0.8% (w/v)] with and without a mechanically stable polymer knitting [poly-caprolactone (PCL)] were prepared. The porous structure of collagen scaffolds was characterized using scanning electron microscopy and hematoxylin-eosin staining. The mechanical strength of hybrid scaffolds (collagen with or without PCL) was determined using tensile strength analysis. Cellular in-growth and interconnectivity were evaluated using fluorescent bead distribution and human bladder smooth muscle cells and human urothelium seeding. The lower density collagen scaffolds showed remarkably deeper cellular penetration and by combining it with PCL knitting the tensile strength was enhanced. This study indicated that a hybrid scaffold prepared from 0.4% collagen strengthened with knitting achieved the best cellular distribution

    Fetal abdominal wall repair with a collagen biomatrix in an experimental sheep model for gastroschisis.

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    Contains fulltext : 70287.pdf (publisher's version ) (Open Access)We evaluated the regeneration of the abdominal wall using a dual-layer collagen biomatrix, and the protective effect on the bowel of fetal abdominal wall repair in a fetal sheep model for gastroschisis. In 14 fetal lambs, the abdominal wall was opened at 79 days' gestation, creating a gastroschisis. In group 1, the gastroschisis was left uncovered. In group 2, the bowel was repositioned, and the defect was closed by suturing a collagen biomatrix into the abdominal wall. A cesarean section was performed at 140 days' gestation, and macroscopic and histological evaluation was performed. In the five lambs with a gastroschisis, the eviscerated part of the bowel was coalescent, showed extensive adhesions, and was covered by fibrous peel. In group 2, the abdominal wall had closed, with a firm connection to the native abdominal wall. The biomatrix was largely degraded and replaced by connective tissue with collagen and fibroblasts, neovascularisation, and scattered muscle cells. Minor or no adhesions of the bowel and no peel formation were observed. Abdominal wall tissue replacement using a collagen biomatrix was feasible in fetal lambs, resulting in a closed abdominal wall at birth. Immediate closure of the gastroschisis strongly diminished or prevented bowel adhesions and peel formation

    Compensatory Hypertrophy in Paediatric Patients with a Unilateral Ureteropelvic Junction Obstruction

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    BACKGROUND: Compensatory hypertrophy is common in children with solitary functioning kidney, but it is unknown whether it also develops in children with unilateral partial reduction of kidney function. OBJECTIVE: The aim of this study was to assess whether children with a unilateral ureteropelvic junction obstruction (UPJO) show compensatory growth of the unaffected kidney. Furthermore, we investigated whether the length of the unaffected kidney was related to the degree of split kidney function lost and other possible risk factors. Lastly, we studied a possible relationship with signs of kidney injury. DESIGN, SETTING, AND PARTICIPANTS: We retrospectively analysed clinical information from 194 children with a unilateral UPJO who participated in the Aetiologic research into Genetic and Occupational/environmental Risk factors for Anomalies in children (AGORA) data- and biobank. Data on kidney length, split kidney function, and other factors possibly associated with kidney length were extracted from electronic patient records. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Pearson’s correlation coefficients between the split kidney function and unaffected kidney length were calculated. Multivariable logistic regression analyses were performed to identify factors associated with kidney length and signs of kidney injury. RESULTS AND LIMITATIONS: Most children with a UPJO had an unaffected kidney length above the reference for age at the end of follow-up (median age 6.5 yr). A correlation with split kidney function was present only in children with a split kidney function of ≥60% in the unaffected kidney (r = 0.41). Aside from split kidney function, UPJO side was the only determinant of kidney length, while no associations between kidney length and kidney injury were identified. CONCLUSIONS: Compensatory growth was visible in most children with a UPJO after sufficient follow-up time and was correlated with split kidney function in children with a severe UPJO. Contralateral kidney length provided no clear prognostic value for developing kidney injury. Studies with more patients and additional biomarkers of kidney injury are needed to further personalise care. PATIENT SUMMARY: Children with obstruction of urine outflow in one kidney often had a larger contralateral kidney. However, the size of this kidney could not be used to predict which children would develop kidney injury

    Prenatal coverage of experimental gastroschisis with a collagen scaffold to protect the bowel

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    <p>Background/Purpose: In fetuses with gastroschisis, toxic products in the amniotic fluid and constriction at the defect of the abdominal wall are considered causative of damage to the eviscerated bowel. The aim of this study was to cover the eviscerated bowel in gastroschisis with a collagen scaffold to protect the bowel and induce cell growth into the scaffold, which could lead to skin or abdominal wall formation replacing the scaffold.</p><p>Methods: In 12 fetal lambs gastroschisis was surgically created at 79 days gestation. A dual-layer type I collagen scaffold was sutured into the skin of the abdominal wall around the defect covering the eviscerated bowel. Lambs were examined after caesarean section at 140 days' gestation.</p><p>Results: Survival was 67%. In 7 of 8 surviving lambs the bowel was found to be covered after birth. One scaffold had ruptured. The bowel was found repositioned in the abdominal cavity in 5 lambs. In 2 lambs it was still partially outside. Only minor adherence of bowel loops and no fibrous peel formation were seen. Connective tissue and skin tissue replaced the scaffold.</p><p>Conclusions: Prenatal coverage of the bowel in experimental gastroschisis with a collagen scaffold is feasible in fetal lambs, significantly diminished damage to the bowel wall, and skin and connective tissue replaced the scaffold. This technique may be promising in the care of fetuses with this congenital anomaly. (C) 2013 Elsevier Inc. All rights reserved.</p>

    Urogenital function after cloacal reconstruction, two techniques evaluated

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    Current surgical techniques for cloacal reconstruction are posterior sagittal anorecto vagino urethroplasty (PSARVUP) and posterior sagittal anorectoplasty (PSARP) with total urogenital mobilization (TUM). The aim of this study was to explore the results of reconstructive cloaca surgery in the Netherlands and evaluate urogenital function after PSARVUP and TUM. Medical records from five pediatric surgical departments in the Netherlands were studied for patients with cloacal malformations treated between 1985 and 2009. Forty-two patients were eligible, and patients with short common channels were categorized into PSARVUP and TUM groups. Groups were compared using Fisher's exact test. Median age at time of surgery was 9 months (range 1-121). In 24 patients (57%) a PSARVUP was done, in 18 patients (43%) TUM. Median follow-up was 142 months (range 15-289). At follow-up spontaneous voiding was seen in 29 patients (69%). Clean intermittent catheterization (CIC) was needed in 14 patients (33%); a urinary diversion was created in 10 patients (24%). In total 32 patients (76%) were dry with no involuntary loss of urine per urethra. Recurrent urinary tract infections were seen in 23 patients (55%). When comparing PSARVUP and TUM groups in our series of patients with short common channels, there were no differences in urological outcome. Normal menstruation was present in 11 of the 20 patients who reached puberty (55%). Urogenital functional outcome after reconstructive surgery for cloacal malformations was similar in PSARVUP and TUM groups in patients with short common channels. A thorough urological follow-up is needed to establish the long-term bladder function and urinary incontinence results to prevent long-term risks of recurrent UTI. Albeit without differences between PSARVUP and TUM groups, 45% of the patients present with abnormal or absent menstruations. Gynecological follow-up is mandatory in all patients with cloacal malformations 6 months after the first sign of pubert

    Genetics of hypospadias: are single-nucleotide polymorphisms in SRD5A2, ESR1, ESR2, and ATF3 really associated with the malformation?

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    Contains fulltext : 88536.pdf (publisher's version ) (Open Access)CONTEXT: Hypospadias is a common congenital malformation of the male external genitalia with a multifactorial etiology. Little is known about the genes involved in hypospadias. A few genetic associations have been reported but mainly in studies of small sample size. Most of these associations have not been replicated. OBJECTIVE: The aim of this study was to investigate whether previously reported associations for four single-nucleotide polymorphisms (SNPs) in genes involved in hormonal pathways could be replicated in a large Dutch hypospadias sample. The SNPs investigated are rs523349 in steroid-5 alpha-reductase (SRD5A2), rs6932902 in estrogen receptor 1 (ESR1), rs2987983 in ESR2, and rs11119982 in activating transcription factor 3 (ATF3). DESIGN, PARTICIPANTS, AND METHODS: We genotyped 620 Caucasian hypospadias cases and 596 controls for these SNPs using TaqMan-based genotyping. RESULTS: We did not replicate the associations of the SNPs in SRD5A2 and ESR1 with hypospadias. The SNPs in ESR2 and ATF3 were borderline associated with hypospadias [odds ratios 0.9 (95% confidence interval 0.7-1.0) and 1.2 (95% confidence interval 1.0-1.4), respectively] but in the opposite direction compared with earlier publications. Stratification according to localization of the urethral opening produced comparable results in the subgroups. CONCLUSIONS: The lack of consistency between our and previously performed studies might represent spurious results or chance findings in our or the earlier studies, differences in criteria used to select the study populations, or a real difference between populations, i.e. different genes contributing to disease risk. These results once again confirm the importance of replication in genetic association approaches.1 mei 201
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