<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<rss version="2.0">
  <channel>
    <title>Wolffenbuttel, K.P.</title>
    <link>http://repub.eur.nl/res/aut/6012/</link>
    <description>List of Publications</description>
    <language>en</language>
    <image>
      <url>http://repub.eur.nl/static-eur/img/logo.png</url>
      <title>RePub, Erasmus University Rotterdam</title>
      <link>http://repub.eur.nl</link>
    </image>
    <item>
      <title>Delayed recognition of disorders of sex development (DSD): A missed opportunity for early diagnosis of malignant germ cell tumors (Article)</title>
      <link>http://repub.eur.nl/res/pub/38248/</link>
      <pubDate>2012-02-03T00:00:00Z</pubDate>
      <description>Disorders of sex development (DSD) are defined as a congenital condition in which development of chromosomal, gonadal or anatomical sex is atypical. DSD patients with gonadal dysgenesis or hypovirilization, containing part of the Y chromosome (GBY), have an increased risk for malignant type II germ cell tumors (GCTs: seminomas and nonseminomas). DSD may be diagnosed in newborns (e.g., ambiguous genitalia), or later in life, even at or after puberty. Here we describe three independent male patients with a GCT; two were retrospectively recognized as DSD, based on the histological identification of both carcinoma in situ and gonadoblastoma in a single gonad as the cancer precursor. Hypospadias and cryptorchidism in their history are consistent with this conclusion. The power of recognition of these parameters is demonstrated by the third patient, in which the precursor lesion was diagnosed before progression to invasiveness. Early recognition based on these clinical parameters could have prevented development of (metastatic) cancer, to be treated by systemic therapy. All three patients showed a normal male 46,XY karyotype, without obvious genetic rearrangements by high-resolution whole-genome copy number analysis. These cases demonstrate overlap between DSD and the so-called testicular dysgenesis syndrome (TDS), of significant relevance for identification of individuals at increased risk for development of a malignant GCT. Copyright </description>
    </item> <item>
      <title>Application of the new classification on patients with a disorder of sex development in Indonesia (Article)</title>
      <link>http://repub.eur.nl/res/pub/34997/</link>
      <pubDate>2012-01-13T00:00:00Z</pubDate>
      <description>Disorder of sex development (DSD) patients in Indonesia most often do not receive a proper diagnostic evaluation and treatment. This study intended to categorize 88 Indonesian patients in accordance with the new consensus DSD algorithm. Diagnostic evaluation including clinical, hormonal, genetic, imaging, surgical, and histological parameters was performed. Fifty-three patients were raised as males, and 34 as females. Of 22 patients with 46, XX DSD, 15 had congenital adrenal hyperplasia, while in one patient, an ovarian Leydig cell tumor was found. In all 58 46, XY DSD patients, 29 were suspected of a disorder of androgen action (12 with an androgen receptor mutation), and in 9, gonadal dysgenesis was found and, in 20, severe hypospadias e.c.i. Implementation of the current consensus statement in a resource-poor environment is very difficult. The aim of the diagnostic workup in developing countries should be to end up with an evidence-based diagnosis. This is essential to improve treatment and thereby to improve the patients' quality of life. </description>
    </item> <item>
      <title>Changes in bladder wall blood oxygen saturation in the overactive obstructed bladder (Article)</title>
      <link>http://repub.eur.nl/res/pub/33319/</link>
      <pubDate>2011-09-01T00:00:00Z</pubDate>
      <description>Purpose: Several studies suggest that hypoxia of the bladder wall contributes to bladder dysfunction but the exact relation between bladder function and blood oxygen saturation, a surrogate marker for hypoxia, is not known. We determined bladder wall blood oxygen saturation in vivo in an animal model of bladder outlet obstruction to establish the exact relation between blood oxygen saturation and bladder function. Materials and Methods: In 8 sham operated and 8 urethrally obstructed guinea pigs we measured blood oxygen saturation of the bladder wall by differential path length spectroscopy before surgery and 8 weeks postoperatively. Urodynamic investigations performed during the whole 8-week period provided data on bladder function. Results: Before surgery and 8 weeks after sham surgery blood oxygen saturation in the bladder wall was between 88% and 95% during filling. It decreased during voiding and returned to greater than 90% within 30 seconds. Eight weeks after obstruction saturation was significantly lower than in the sham operated group during filling and voiding. The decrease was positively related to bladder pressure during filling and voiding, and was more pronounced when overactivity was present. Local bladder contractions occurred without a measurable increase in bladder pressure but were associated with a decrease in saturation. Conclusions: A normal bladder maintains a high oxygen saturation level during filling. Bladder obstruction compromises this ability, especially when it involves overactivity. Local bladder contractions without a measurable increase in bladder pressure were associated with a decrease in blood saturation. </description>
    </item> <item>
      <title>A pathologist's view on the testis biopsy (Article)</title>
      <link>http://repub.eur.nl/res/pub/31248/</link>
      <pubDate>2011-08-01T00:00:00Z</pubDate>
      <description>Aspects of the biopsy of the testis from the pathologist's point of view are discussed. Direct enzyme-histochemical staining for alkaline phosphatase (dAP) on frozen sections of biopsies taken during operation is a useful diagnostic tool to aid surgeons in testis-sparing surgery. Biopsy of the contralateral testis for the diagnosis of carcinoma in situ (CIS) in patients with a testicular germ cell tumour is not standard of care in most countries because of the high rate of negative biopsies. Based on risk factors for germ cell tumours, i.p. microlithiasis, a patient population is defined in which the rate of CIS in the contralateral biopsy is about 25%. It is reiterated that the diagnosis of CIS in testicular biopsies requires expertise, and should not be carried out without immunohistochemistry for markers for CIS. As OCT3/4 is increasingly used as marker, it is important to be aware that it may be false-negative in biopsies fixed in Bouin's or Stieve's fixative. Preliminary results are presented on a series of biopsies from cryptorchid testes in infants and children allowing the definition of morphological and immunohistochemical criteria for delayed maturation of gonocytes and pre-CIS. © 2011 The Authors. International Journal of Andrology </description>
    </item> <item>
      <title>Gonadal pathology and tumor risk in relation to clinical characteristics in patients with 45,X/46,XY mosaicism (Article)</title>
      <link>http://repub.eur.nl/res/pub/33379/</link>
      <pubDate>2011-07-01T00:00:00Z</pubDate>
      <description>Context: Gonadectomy is avoided whenever possible in boys with 45,X/46,XY. However, no clinical markers are currently available to guide clinicians in predicting gonadal tumor risk or hormone production. Objective: The objective of the study was to test the hypothesis that gonadal histology and risk for development of a malignant germ cell tumor are reflected by the clinical presentation of a 45,X/46,XY individual. Design: The design of the study was the correlation of clinical data [external masculinization score (EMS), pubertal outcome] with pathology data (gonadal phenotype, tumor risk). Setting: This was a multicenter study involving two multidisciplinary disorder of sex development teams. Patients: Patients included genetically proven 45,X/46,XY (and variants) cases, ofwhomat leastone gonadal biopsy or gonadectomy specimen was available, together with clinical details. Interventions: Patients (n = 48) were divided into three groups, based on the EMS. Gonadal histology and tumor risk were assessedonparaffin-embedded samples (n = 87) by morphology and immunohistochemistry on the basis of established criteria. Main Outcome Measures: Gonadal differentiation and tumor risk in the three clinical groups were measured. Clinical outcome in patients with at least one preserved gonad was also measured. Results: Tumor risk in the three groups was significantly related to the gonadal differentiation pattern (P &lt; 0.001). In boys, hormone production was sufficient and was not predicted by the EMS. Conclusions: The EMS reflects gonadal differentiation and tumor risk in patients with 45,X/46,XY. In boys, testosterone production is often sufficient, but strict follow-up is warranted because of malignancy risk, which appears inversely related to EMS. In girls, tumor risk is limited but gonads are not functional, makinggonadectomythemostreasonable option. Copyright </description>
    </item> <item>
      <title>Gonadal development and tumor formation at the crossroads of male and female sex determination (Article)</title>
      <link>http://repub.eur.nl/res/pub/34548/</link>
      <pubDate>2011-07-01T00:00:00Z</pubDate>
      <description>Malignant germ cell tumor (GCT) formation is a well-known complication in the management of patients with a disorder of sex development (DSD). DSDs are defined as congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. DSD patients in whom the karyotype - at least at the gonadal level - contains (a part of) the Y chromosome are at increased risk for neoplastic transformation of germ cells, leading to the development of the so-called 'type II germ cell tumors'. However, tumor risk in the various forms of DSD varies considerably between the different diagnostic groups. This contribution integrates our actual knowledge on the pathophysiology of tumor development in DSDs, recent findings on gonadal (mal)development in DSD patients, and possible correlations between the patient's phenotype and his/her risk for germ cell tumor development. Copyright </description>
    </item> <item>
      <title>Tumor risk in disorders of sex development (Article)</title>
      <link>http://repub.eur.nl/res/pub/28631/</link>
      <pubDate>2010-09-01T00:00:00Z</pubDate>
      <description>Certain patients with disorders of sex development (DSD), who bear Y chromosome material in their karyotype, are at increased risk for the development of type II germ cell tumors (GCT), which arise from early fetal germ cells. DSD gonads frequently harbor immature germ cells which express early fetal germ cell markers. Some of them (e.g. OCT3/4 and NANOG) seem to be of pathogenetic relevance in GCT development providing cells with the ability of pluripotency, proliferation and apoptosis suppression. Also TSPY (testis-specific protein Y-encoded), the main candidate for the so-called gonadoblastoma locus on Y chromosome, is overexpressed in germ cells of DSD patients and possibly contributes to their survival and proliferation. Nowadays, the use of immunohistochemical methods is highly relevant in identifying DSD gonads at risk. The risk for GCT development varies. While the prevalence of GCT is 15% in patients with partial androgen insensitivity, it may reach more than 30% in patients with gonadal dysgenesis. Patients with complete androgen insensitivity and ovotesticular DSD develop malignancies in 0.8% and 2.6% of cases, respectively. However, these data may be biased for various reasons. To better estimate the risk in individual groups of DSD, further investigations on large patient series are needed. Copyright </description>
    </item> <item>
      <title>Gonadal tumours and DSD (Article)</title>
      <link>http://repub.eur.nl/res/pub/28586/</link>
      <pubDate>2010-04-01T00:00:00Z</pubDate>
      <description>Disorders of sex development (DSD), previously referred to as intersex, has been recognised as one of the main risk factors for development of type II germ cell tumours (GCTs), that is, seminomas/dysgerminomas and non-seminomas (e.g., embryonal carcinoma, yolk sac tumour, choriocarcinoma and teratoma). Within the testis, this type of cancer is the most frequent malignancy in adolescent and young adult Caucasian males. Although these males are not known to have dysgenetic gonads, the similarities in the resulting tumours suggest a common aetiological mechanism(s), -genetically, environmentally or a combination of both. Within the group of DSD patients, being in fact congenital conditions, the risk of malignant transformation of germ cells is highly heterogeneous, depending on a number of parameters, some of which have only recently been identified. Understanding of these recent insights will stimulate further research, with the final aim to develop an informative clinical decision tree for DSD patients, which includes optimal (early) diagnosis without overtreatment, such as prophylactic gonadectomy in the case of a low tumour risk. </description>
    </item> <item>
      <title>Isolated 17,20-lyase deficiency due to the cytochrome b5 mutation W27X (Article)</title>
      <link>http://repub.eur.nl/res/pub/27514/</link>
      <pubDate>2010-03-01T00:00:00Z</pubDate>
      <description>Context: Cytochrome P450c17 (P450c17) is a bifunctional enzyme necessary for the production of glucocorticoids (17-hydroxylase activity) and sex steroids (17,20-lyase activity). Isolated 17,20-lyase deficiency is a rare condition characterized by a deficient production of androgens resulting in 46,XY disorders of sex development (DSD) while the production of glucocorticoids is intact. Several missense mutations in the CYP17A1 gene are known to cause this condition. Cytochrome b5(CytB5) is an important factor in 17,20-lyase activity, probably by acting as an allosteric factor. Objective: The aim of this study was to investigate the role of CytB5 in a patient with defective 17,20-lyase activity. Setting: We conducted the study in a pediatric outpatient clinic of a University Hospital. Patients: We studied a 46,XY DSD patient with 17,20-lyase deficiency without missense mutation in the CYP17A1 gene and his parents. Main Outcome Measures: We sequenced the CYB5 gene and measured steroid hormone levels. Results: Analysis of the CYB5 gene in our patient revealed a homozygous W27X mutation, leading to the formation of a premature stop codon; his parents were both heterozygous carriers of this mutation. This mutation results in the absence of residues E48 and E49 of CytB5, which are necessary for an intact 17,20-lyase activity. Conclusion: We demonstrated 17,20-lyase deficiency due to an aberrant CytB5. Our findings thus provide evidence for an alternative etiology for this disorder. Copyright </description>
    </item> <item>
      <title>Lack of correlation between phenotype and genotype in untreated 21-hydroxylase-deficient Indonesian patients (Article)</title>
      <link>http://repub.eur.nl/res/pub/24768/</link>
      <pubDate>2009-11-01T00:00:00Z</pubDate>
      <description>Background Mutations in CYP21A2 lead to deficiency of 21-hydroxylase and can have either severe or moderate effects on phenotype, which can be prevented by early treatment. We studied long-term effects of this deficiency on phenotype in patients who had not been treated for prolonged periods and correlated these phenotypes with the mutations found in our patients. Objective To assess the correlation between genotype and phenotype in untreated patients with 21-hydroxylase deficiency. Design Subjects with 21-hydroxylase deficiency were selected from a large population of Indonesian patients with disorders of sexual differentiation. CYP21A2 mutations in these patients were correlated with their phenotype in terms of genital development and steroid hormone levels. Patients Fifteen 46,XX patients with ages between 1 and 33 years, of whom 12 had never been treated before. Measurements Mutations in CYP21A2, genital phenotype and steroid hormone levels. Results We found in all patients CYP21A2 mutations which affect enzyme activity, with a relatively high allele frequency of R356W (40%), I172N (20%) and IVS2 - 1A &gt; G (13%). Clitoris length was directly correlated with levels of testosterone, but not with age. The phenotype was not always concordant with the genotype: different phenotypes (mild to severe virilization) were found in sibling pairs with the mutations IVS2 - 13A &gt; G or I172N. The high frequency of homozygous mutants for R356W in patients aged from 1 to 11 years old is remarkable, as this mutation has been described only in salt-wasting patients. In our study, this mutation caused a urogenital sinus in three out of seven cases, whereas in the remaining cases the labia were at least partially fused. This mutation caused severe virilization with remarkably high serum levels of renin. We found one novel substitution in intron 2 (IVS2 - 37A &gt; G), containing the branch site, which is likely to affect the CYP21-enzyme. Two additional intron 2 substitutions were discovered, which are supposed to affect the 21-hydroxylase (i.e. IVS2 + 33A &gt; C and IVS2 + 67C &gt; T). Conclusion We conclude that a correlation exists between the concentration of androgens and the extent of virilization. However, there was no clear correlation between genotype and phenotype, except for the mutation R356W. </description>
    </item> <item>
      <title>Perinatal testicular torsion: New insights and policy advice (Article)</title>
      <link>http://repub.eur.nl/res/pub/24134/</link>
      <pubDate>2009-10-01T00:00:00Z</pubDate>
      <description>Perinatal testicular torsion is a rare event with a very poor salvage rate by neonatal emergent operation. In addition, there is a small risk of asynchronous contralateral testicular torsion. In case of a suspected testicular torsion we advise urgent consultation of a pediatric urologist from a children's hospital with neonatal anesthetic care. Then, the prospect for 'salvage' of the testicle and a possible indication for emergent intervention can be assessed. The goal of a (semi-)emergent exploration is 'salvage' of the affected testicle and/or prevention of contralateral asynchronous torsion.</description>
    </item> <item>
      <title>Disorders of sex development: Update on the genetic background, terminology and risk for the development of germ cell tumors (Article)</title>
      <link>http://repub.eur.nl/res/pub/32678/</link>
      <pubDate>2009-07-27T00:00:00Z</pubDate>
      <description>Background: Considerable progress has been made on genetic mechanisms involved in disorders of sex development and on tumor formation in dysgenetic gonads. Clinical and psychological outcome of patients are, as far as evaluated, unsatisfactory at present. Guidelines are emerging in order to optimize long-term outcome in the future. Data sources: The information obtained in this review is based on recent original publications and on the experience of our multidisciplinary clinical and research group. Results: This review offers an update on our knowledge concerning gene mutations involving in disorders of sex development, on the renewed nomenclature and classification system, and on the mechanisms of tumor development in patients. Conclusions: The consensus meeting on disorders of sex development has renewed our interest in clinical studies and long-term outcome of patients. Psychological research emphasizes the importance to consider male gender identity wherever possible in cases of severe undervirilization. Patient advocacy groups demand a more conservative approach regarding gonadectomy. Medical doctors, scientists and governmental instances are increasingly interested in the set-up of international research collaborations. As a consequence, it is expected that new guidelines for the optimal care of patients will be proposed in the coming years. </description>
    </item> <item>
      <title>A novel mutation F826L in the human androgen receptor in partial androgen insensitivity syndrome; increased NH2-/COOH-terminal domain interaction and TIF2 co-activation (Article)</title>
      <link>http://repub.eur.nl/res/pub/29654/</link>
      <pubDate>2008-09-24T00:00:00Z</pubDate>
      <description>A novel mutation F826L located within the ligand binding domain (LBD) of the human androgen receptor (AR) was investigated. This mutation was found in a boy with severe penoscrotal hypospadias (classified as 46,XY DSD). The AR mutant F826L appeared to be indistinguishable from the wild-type AR, with respect to ligand binding affinity, transcriptional activation of MMTV-luciferase and ARE2-TATA-luciferase reporter genes, protein level in genital skin fibroblasts (GSFs), and sub-cellular distribution in transfected cells. However, an at least two-fold higher NH2-/COOH-terminal domain interaction was found in luciferase and GST pull-down assays. A two-fold increase was also observed for TIF2 (transcription intermediary factor 2) co-activation of the AR F826L COOH-terminal domain. This increase could not be explained by a higher stability of the mutant protein, which was within wild-type range. Repression of transactivation by the nuclear receptor co-repressor (N-CoR) was not affected by the AR F826L mutation. The observed properties of AR F826L would be in agreement with an increased activity rather than with a partial defective AR transcriptional activation. It is concluded that the penoscrotal hypospadias in the present case is caused by an as yet unknown mechanism, which still may involve the mutant AR. </description>
    </item> <item>
      <title>New insights into type II germ cell tumor pathogenesis based on studies of patients with various forms of disorders of sex development (DSD) (Article)</title>
      <link>http://repub.eur.nl/res/pub/29703/</link>
      <pubDate>2008-09-10T00:00:00Z</pubDate>
      <description>Disorders of sex development (DSD), previously known as intersex, refer to congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. Patients with specific variants of this disorder have an elevated risk for the development of so-called type II germ cell cancers, i.e., the seminomatous and nonseminatous tumors, referred to as germ cell tumors (GCTs). Specifically DSD patients with gonadal dysgenesis or hypovirilization are at risk. A prerequisite for type II GCT formation is the presence of a specific part of the Y chromosome (referred to as the GBY region), with the TSPY gene being the most likely candidate. Also the octamer binding transcription factor OCT3/4 is consistently expressed in all type II GCTs with pluripotent potential, as well as in the precursor lesions carcinoma in situ (CIS) in case of a testis and gonadoblastoma (GB) in the DSD gonad. The actual risk for malignant transformation in individual DSD patients is hard to predict, because of confusing terminology referring to the different forms of DSD, and unclear criteria for identification of the presence of malignant germ cells, especially in young patients. This is specifically due to the phenomenon of delay of germ cell maturation, which might result in over diagnosis. This review will give novel insight into the pathogenesis of the type II GCTs through the study of patients with various forms of DSD for which the underlying molecular defect is known. To allow optimal understanding of the pathogenesis of this type of cancers, first normal gonadal development, especially regarding the germ cell lineage, will be discussed, after which type II GCTs will be introduced. Subsequently, the relationship between type II GCTs and DSD will be described, resulting in a number of new insights into the development of the precursor lesions of these tumors. </description>
    </item> <item>
      <title>Stem cell factor as a novel diagnostic marker for early malignant germ cells (Article)</title>
      <link>http://repub.eur.nl/res/pub/15949/</link>
      <pubDate>2008-09-01T00:00:00Z</pubDate>
      <description>Carcinoma in situ (CIS) of the testis is the pre-invasive stage of type II testicular germ cell tumours (TGCTs) of adolescents and adults. These tumours are the most frequently diagnosed cancer in Caucasian adolescents and young adults. In dysgenetic gonads, the precursor of type II GCTs can be either CIS or a lesion known as gonadoblastoma (GB). CIS/GB originates from a primordial germ cell (PGC)/gonocyte, ie an embryonic cell. CIS can be cured by local low-dose irradiation, with limited side effects on hormonal function. Therefore, strategies for early diagnosis of CIS are essential. Various markers are informative to diagnose CIS in adult testis by immunohistochemistry, including c-KIT, PLAP, AP-2γ, NANOG, and POU5F1 (OCT3/4). OCT3/4 is the most informative and consistent in presence and expression level, resulting in intense nuclear staining. In the case of maturational delay of germ cells, frequently present in gonads of individuals at risk for type II (T)GCTs, use of these markers can result in overdiagnosis of malignant germ cells. This demonstrates the need for a more specific diagnostic marker to distinguish malignant germ cells from germ cells showing maturation delay. Here we report the novel finding that immunohistochemical detection of stem cell factor (SCF), the c-KIT ligand, is informative in this context. This was demonstrated in over 400 cases of normal (fetal, neonatal, infantile, and adult) and pathological gonads, as well as TGCT-derived cell lines, specifically in cases of CIS and GB. Both membrane-bound and soluble SCF were expressed, suggestive of an autocrine loop. SCF immunohistochemistry can be a valuable diagnostic tool, in addition to OCT3/4, to screen for precursor lesions of TGCTs, especially in patients with germ cell maturation delay.</description>
    </item> <item>
      <title>The detrusor glycogen content of a de-obstructed bladder reflects the functional history of that bladder during PBOO (Article)</title>
      <link>http://repub.eur.nl/res/pub/29775/</link>
      <pubDate>2008-07-21T00:00:00Z</pubDate>
      <description>Aims: To determine if detrusor glycogen content in a bladder after removal of a urethral obstruction reflects the situation of bladder dysfunction as it existed during the period of obstruction. Methods: The glycogen content of the detrusor was scored using a Periodic Acid Schiff's (PAS) staining. It was related to the functional history of the bladder. Bladder tissue was obtained from a guinea-pig model for posterior urethral valves where animals had been obstructed for up to 10 weeks, de-obstructed and allowed to recover for 2-8 weeks. Bladder urodynamic function had been documented with multiple measurements for the complete period of obstruction and de-obstruction. Results: The degree of glycogen deposition in a bladder after de-obstruction correlated directly with bladder function during obstruction. The strongest glycogen deposition was found in bladders having experienced the highest pressures, most instabilities, lowest compliance and highest contractility. In contrast, the bladder glycogen content was not related to the function of the bladder at the day the tissue was obtained, except for a relation between high glycogen content and continuing low compliance. Conclusions: The glycogen content of a bladder reflects the history of bladder dysfunction, also when measured during a recovery period. This window on the functional history of a bladder may be of clinical value for picking out potential bad-responders to therapy in patients with incomplete data on bladder function during a previous period of bladder obstruction. </description>
    </item> <item>
      <title>FOXL2 and SOX9 as parameters of female and male gonadal differentiation in patients with various forms of disorders of sex development (DSD) (Article)</title>
      <link>http://repub.eur.nl/res/pub/28917/</link>
      <pubDate>2008-05-01T00:00:00Z</pubDate>
      <description>The transcription factors SOX9 and FOXL2 are required for male and female mammalian gonadal development. We have used specific antibodies to investigate the role of these key proteins in disorders of sex development (DSD), specifically inter-sex states. In normal gonads, SOX9 was found to be restricted to the presence of (pre-)Sertoli cells, while FOXL2 was found in granulosa cells, and in stromal cells interpreted as early ovarian stroma. Both proteins were found within a single patient, when testicular and ovarian development was present; and within the same gonad, when both differentiation lineages were identified, as in ovotesticular DSD (ie hermaphrodite). Especially SOX9 was informative to support the presence of early testicular development (ie seminiferous tubules), expected based on morphological criteria only. In a limited number of DSD cases, FOXL2 was found within reasonably well-developed seminiferous tubules, but double staining demonstrated that it was never strongly co-expressed with SOX9 in the same cell. All seminiferous tubules containing carcinoma in situ (CIS), the malignant counterpart of a primordial germ cell, ie the precursor of type II germ cell tumours of the testis, seminomas and non-seminomas, showed the presence of SOX9 and not FOXL2. In contrast, gonadoblastomas (GBs), the precursor of the same type of cancer, in a dysgenetic gonad, showed expression of FOXL2 and no, or only very low, SOX9 expression. These findings indicate that gonadal differentiation, ie testicular or ovarian, determines the morphology of the precursor of type II germ cell tumours, CIS or GB, respectively. We show that in DSD patients, the formation of either ovarian or/and testicular development can be visualized using FOXL2 and SOX9 expression, respectively. In addition, it initiates a novel way to study the role of the supportive cells in the development of either CIS or GB. Copyright </description>
    </item> <item>
      <title>Prolonged follow-up after paediatric pyeloplasty: Are repeat scans necessary? (Article)</title>
      <link>http://repub.eur.nl/res/pub/36859/</link>
      <pubDate>2007-11-01T00:00:00Z</pubDate>
      <description>OBJECTIVE: To establish the value of repeat renal scans to assess the relative renal function after successful paediatric pyeloplasty. PATIENTS AND METHODS: Renal scans were assessed from 138 patients after successful pyeloplasty; the relative renal function before and immediately after pyeloplasty were compared, as was split renal function at 3.5 and 5.5 years after surgery. RESULTS: With a few exceptions the relative renal function before and after pyeloplasty was stable. Repeat renal scans 3.5 and 5.5 years after surgery also showed stable split renal function, even if the renal function was already diminished. CONCLUSIONS: Repeat renal scans are not necessary after successful pyeloplasty in children, as most operated renal units showed stable renal function for 5-7 years. Further studies are needed to investigate whether renal function changes further after puberty. </description>
    </item> <item>
      <title>The Effect of Oxybutynin on Structural Changes of the Obstructed Guinea Pig Bladder (Article)</title>
      <link>http://repub.eur.nl/res/pub/35152/</link>
      <pubDate>2007-10-01T00:00:00Z</pubDate>
      <description>Purpose: Oxybutynin is used clinically to lower intravesical pressure and detrusor overactivity. In vitro it inhibits stretch induced bladder smooth muscle cell proliferation. We tested whether oxybutynin also prevents hypertrophic bladder changes in vivo in a model of partial bladder obstruction. Materials and Methods: Subvesical obstruction was induced in immature guinea pigs by a silver ring around the urethra. Eight animals received 0.4 mg oxybutynin per kg body weight per day in 2 doses. Control groups were obstructed without oxybutynin treatment or sham operated. Urodynamic pressure flow studies were performed at 1-week intervals for 10 weeks in all animals under anesthesia with ketamine/xylazine. After 10 weeks the animals were sacrificed and the bladder was removed for structural analysis with periodic acid-Schiff stain, in which the number of glycogen granules was also scored as a measure of previous ischemia. Results: Compared to the sham treated group obstructed animals had significantly higher intravesical pressure and detrusor overactivity, lower compliance and increased contractility. Obstructed animals that received oxybutynin retained normal intravesical pressure, detrusor overactivity and compliance. Their bladder contractility increased as in obstructed animals. The oxybutynin group showed less collagen infiltration in the detrusor and fewer glycogen granules compared to those in obstructed animals. Conclusions: Our results demonstrate that oxybutynin has a protective effect on bladder function and structure. Prevention of hypertrophic and ischemic bladder changes is an argument for an early start of oxybutynin treatment in children with inborn neurogenic bladder dysfunction, such as spina bifida, or in patients with urethral valves. </description>
    </item> <item>
      <title>Detrusor glycogen reflects the functional history of bladders with partial outlet obstruction (Article)</title>
      <link>http://repub.eur.nl/res/pub/36868/</link>
      <pubDate>2007-10-01T00:00:00Z</pubDate>
      <description>OBJECTIVE: To assess the relationship between glycogen content in bladder detrusor tissue and historical bladder function in a guinea-pig model of partial bladder outlet obstruction (PBOO). MATERIALS AND METHODS: In male immature guinea pigs PBOO was created with a silver ring around the proximal urethra; a control group had a sham operation for comparison. Longitudinal individual urodynamic data were obtained weekly, so that guinea pigs were killed at different levels of bladder dysfunction. Bladder sections were stained with periodic acid-Schiff (PAS) to assess overall morphology and glycogen granule density, scored from 0 (no glycogen) to 3. Glycogen scores were related to both the end-stage and historical extremes of bladder function values. RESULTS: Glycogen granules were seen only in the detrusor; as their number increased their location expanded from only close to the serosa (glycogen score 1), through the detrusor (score 2) up to the urothelium (score 3). A glycogen score of 0 correlated with normal values for all urodynamic variables. Compared with a glycogen score of 0 a score of 1 correlated with significant (P &lt; 0.05) changes in end-stage compliance (decrease) and contractility (increase) and significantly higher historical values for contractility, pressure and number of unstable contractions (NUC). In the group with a glycogen score of 2 there were significant changes in both the end-stage values and historical extremes for compliance, pressure, contractility and NUC (all P &lt; 0.05). In the group with a glycogen score of 3 all these changes were even more dramatic, except for the end-stage contractility, for which the increase was not significant. From glycogen score 0 to score 3 all changes increased in magnitude. CONCLUSION: A high glycogen content reflects a history of abnormal urodynamic function. This finding exemplifies the added value of structural analysis to urodynamic studies. Further studies are needed to relate bladder structure to the potential for functional recovery. </description>
    </item> <item>
      <title>Genome-wide analysis for micro-aberrations in familial exstrophy of the bladder using array-based comparative genomic hybridization (Article)</title>
      <link>http://repub.eur.nl/res/pub/36879/</link>
      <pubDate>2007-09-01T00:00:00Z</pubDate>
      <description>OBJECTIVE: Exstrophy of the bladder (EB) is part of the bladder-exstrophy-epispadias complex (BEEC). Because familial occurrence of BEEC is rare, exogenous factors are thought to play a major role in the etiology of most BEEC cases. We aimed to investigate a possible genetic basis of BEEC in a consanguineous kindred of Moroccan origin with three members showing the same phenotypic expression of BEEC. PATIENTS AND METHODS: The three affected males (two cousins and their maternal uncle) all presenting with nonsyndromic classic EB, were born in Morocco or The Netherlands. One Moroccan patient had an open bladder surface for 22 years due to late surgical reconstruction, avoided upright posture and developed severe lumbar scoliosis. Because three maternally related males from a consanguineous family living in different environments are affected, a genetic basis for EB is likely in this family. To screen for chromosomal aberrations and micro-aberrations in the two patients who were still alive, conventional karyotyping and array-based comparative genomic hybridization (array-CGH) were used on DNA-microarrays with a genome-wide average resolution of &lt;0.5 Mb. RESULTS: Chromosome banding revealed normal karyotypes. By array-CGH, one of 8000 clones was aberrant in both affected cousins. This clone from 1p21.1 contained the AMY1B, AMY2B, AMY2A genes coding for salivary and pancreatic amylases. CONCLUSION: The aberration detected by array-CGH in both affected cousins is a known copy-number variant and most likely unrelated to the EB-phenotype. Nevertheless, in this family the nonsyndromic EB could be a monogenic disorder inherited in an autosomal-recessive or X-linked fashion. </description>
    </item> <item>
      <title>Tumor risk in disorders of sex development (DSD) (Article)</title>
      <link>http://repub.eur.nl/res/pub/36972/</link>
      <pubDate>2007-09-01T00:00:00Z</pubDate>
      <description>Disorders of sex development (DSD), previously referred to as intersex disorders, comprise a variety of anomalies defined by congenital conditions in which chromosomal, gonadal, or anatomical sex is atypical. Besides issues such as gender assignment, clinical and diagnostic evaluation, surgical and psychosocial management, and sex steroid replacement, the significantly increased risk for developing specific types of malignancies is both clinically and biologically relevant. This relates to germ-cell tumors specifically in DSD patients with hypovirilization or gonadal dysgenesis. The presence of a well-defined part of the Y chromosome (known as the GBY region) is a prerequisite for malignant transformation, for which the testis-specific protein on the Y chromosome (TSPY) is a likely candidate gene. The precursor lesions of these cancers are carcinoma in situ (CIS)/intratubular germ-cell neoplasia unclassified (ITGCNU) in testicular tissue and gonadoblastoma in those without obvious testicular differentiation. Most recently, undifferentiated gonadal tissue (UGT) has been identified as the likely precursor for gonadoblastoma. The availability of markers for the different developmental stages of germ cells allows detailed investigation of the characteristics of normal and (pre)malignant germ cells. Although informative in a diagnostic setting for adult male patients, these markers - such as OCT3/4 - cannot easily distinguish (pre)malignant germ cells from germ cells showing delayed maturation. This latter phenomenon is frequently found in gonads of DSD patients, and may be related to the risk of malignant transformation. Thus, the mere application of these markers might result in over-diagnosis and unnecessary gonadectomy. It is proposed that morphological and histological evaluation of gonadal tissue, in combination with OCT3/4 and TSPY double immunohistochemistry and clinical parameters, is most informative in estimating the risk for germ-cell tumor development in the individual patient, and might in future be used to develop a decision tree for optimal management of patients with DSD. </description>
    </item> <item>
      <title>Impact of the Y-containing cell line on histological differentiation patterns in dysgenetic gonads (Article)</title>
      <link>http://repub.eur.nl/res/pub/36050/</link>
      <pubDate>2007-08-01T00:00:00Z</pubDate>
      <description>Objective: Gonadal karyotyping is considered a tool for increasing our knowledge of disturbed gonadal development in patients with gonadal dysgenesis and for estimating more accurately the risk for gonadoblastoma formation. The objective was to gain insight into the role of Y chromosome distribution in the histological heterogeneity of gonads of patients with gonadal dysgenesis. Design: Investigation of the possible relationship between peripheral blood karyotype, gonadal karyotype, morphological differentiation patterns of dysgenetic gonads and tumour formation. Patients: In total 22 gonadal samples from 19 patients with gonadal dysgenesis (45,X/46,XY and variants n = 14; 46,XY: n = 3; 46,XX: n = 2) were examined. Measurements: Morphological examination and immunohistochemical staining for testis specific protein, Y encoded (TSPY) and fluorescent and nonfluorescent in situ hybridization directly on gonadal tissue. Results: No correlation was observed between peripheral blood karyotype and gonadal karyotype or between gonadal karyotype and the corresponding differentiation pattern. A Y-containing cell line in Sertoli cells was encountered no more frequently than were other cell types. Conclusions: The distribution of the Y-containing cell line in peripheral blood is not a suitable indicator for predicting the histological differentiation pattern found in the gonads of patients with gonadal dysgenesis. The analysis of Y-containing cell lines in the gonads of such patients could be informative with regard to the specific characteristics of gonadal development in humans as compared to chimeric mouse models. Moreover, it is essential to understand the mechanisms underlying disturbed gonadogenesis in these patients. As the gonadal karyotype is not related to the encountered gonadal differentiation pattern, it does not allow prediction of the risk for gonadoblastoma formation. </description>
    </item> <item>
      <title>Is the impaired flow after hypospadias correction due to increased urethral stiffness? (Article)</title>
      <link>http://repub.eur.nl/res/pub/7737/</link>
      <pubDate>2006-05-18T00:00:00Z</pubDate>
      <description>Purpose: A low flow rate without clinical symptoms is commonly found in boys 
after hypospadias correction. Urethral calibration usually shows no abnormalities. 
We investigated whether this flow rate impairment might be caused by increased 
neo-urethral wall-stiffness. Methods: From Polyvinyl Alcohol cryogel two models 
of the urethra were made, a hypospadias model and a control model. Both models 
had a constant and equal inner diameter and equal compliance. The hypospadias 
model had a less compliant distal segment mimicking the distal neo-urethra after 
hypospadias correction. In both models flow rate was recorded as a function of 
bladder pressure. To test whether the length of the less compliant segment had an 
effect on the flow rate, both models were shortened by cutting off 1 cm segments. 
Results: In a physiological range of bladder pressures (10 - 130 cmH2O) the mean 
flow rate(± 1sem) in the hypospadias model was 2.8± 0.3 ml/s, significantly lower 
(p &lt; .05) than in the control model (5.4 ± 0.6 ml/s). Shortening of the hypospadias 
model showed some increase in flow rate, however not statistically significant. In 
the control model there was also no significant variation in flow rate. Conclusion: 
We showed that a low compliant segment of a urethral model reduces the flow rate. 
Extrapolating these results to asymptomatic boys with a low urinary flow rate after 
hypospadias repair might justify a watchful waiting policy.</description>
    </item> <item>
      <title>Morphological and immunohistochemical differences between gonadal maturation delay and early germ cell neoplasia in patients with undervirilization syndromes. (Article)</title>
      <link>http://repub.eur.nl/res/pub/13866/</link>
      <pubDate>2005-09-01T00:00:00Z</pubDate>
      <description>CONTEXT: Maturation delay of germ cells and their progression into carcinoma in situ (CIS) frequently occurs in intersex patients. A developmentally delayed germ cell resembles a CIS cell and displays prolonged expression of immunohistochemical markers used for the diagnosis of CIS. This questions their applicability in young children. OBJECTIVE: The objective of the study was the elaboration of tools to distinguish germ cells with maturation delay and CIS. DESIGN: The design was a qualitative and quantitative analysis of the expression of diagnostic markers for CIS in gonads of young patients with undervirilization syndromes. Setting: The study was conducted in the pathology department of a university center, specializing in germ cell tumor pathogenesis. PATIENTS: Fifty-eight formalin-fixed, paraffin-embedded testicular tissue samples of 30 undervirilized patients (1 month to 23 yr of age) were analyzed. Interventions: Interventions included hematoxylin-eosin staining, immunohistochemistry for octamer binding transcription factor (OCT)3/4, gene encoding the stem cell factor receptor that has tyrosine kinase activity c-KIT, placental/germ alkaline phosphatase (PLAP), testis-specific protein Y encoded (TSPY), and VASA, double staining for OCT3/4 and VASA, with ploidy determination by fluorescent in situ hybridization. MAIN OUTCOME MEASURE: Maturation delay and CIS are characterized by the staining patterns of the immunohistochemical markers. RESULTS: CIS was diagnosed in three of 30 patients (10%) and four of 58 gonads (6.9%). Patient age, distribution of OCT3/4-positive cells throughout the gonad, and their position within the seminiferous tubule differ between maturation delay and CIS. Abnormal OCT3/4 and testis-specific protein Y encoded expression appear to be of pathogenetic relevance in the development of these lesions. CONCLUSION: The dimorphic expression of OCT3/4 allows distinction between maturation delay and CIS. Studies in larger patient series are essential before a biopsy to evaluate the neoplastic risk can eventually be proposed as an alternative for gonadectomy.</description>
    </item> <item>
      <title>POU5F1 (OCT3/4) identifies cells with pluripotent potential in human germ cell tumors (Article)</title>
      <link>http://repub.eur.nl/res/pub/10129/</link>
      <pubDate>2003-01-01T00:00:00Z</pubDate>
      <description>Human germ cell tumors (GCTs) may have variable histology and clinical
      behavior, depending on factors such as sex of the patient, age at clinical
      diagnosis, and anatomical site of the tumor. Some types of GCT, i.e., the
      seminomas/germinomas/dysgerminomas and embryonal carcinomas (the stem cell
      component of nonseminomas), have pluripotent potential, which is
      demonstrated by their capacity to differentiate into somatic and/or
      extraembryonic elements. Although embryonal carcinoma cells are
      intrinsically pluripotent, seminoma/germinoma/dysgerminoma cells, as well
      as their precursor carcinoma in situ/gonadoblastoma cells, have the
      phenotype of early germ cells that can be activated to pluripotency. The
      other types of GCT (teratomas and yolk sac tumors of infants and newborn,
      dermoid cyst of the ovary, and spermatocytic seminoma of elderly) are
      composed of (fully) differentiated tissues and lack the appearance of
      undifferentiated and pluripotent stem cells. OCT3/4, a transcription
      factor also known as OTF3 and POU5F1, is involved in regulation of
      pluripotency during normal development and is detectable in embryonic stem
      and germ cells. We analyzed the presence of POU5F1 in GCT and other tumor
      types using immunohistochemistry. The protein was consistently detected in
      carcinoma in situ/gonadoblastoma, seminomas/germinoma/dysgerminoma, and
      embryonal carcinoma but not in the various types of differentiated
      nonseminomas. Multitumor tissue microarray analysis covering &gt;100
      different tumor categories and 3600 individual cancers verified that
      POU5F1 expression is specific for particular subtypes of GCT of adults. No
      protein was observed in GCT of newborn and infants, spermatocytic
      seminomas, and the various tumors of nongerm cell origin. In addition, no
      difference in staining pattern was found in chemosensitive and
      chemoresistant GCT of adults. These results indicate preservation of the
      link between POU5F1 and pluripotency, as reported during normal
      development, after malignant transformation. Therefore, POU5F1
      immunohistochemistry is an informative diagnostic tool for pluripotent GCT
      and offers new insights into the histological heterogeneity of this
      cancer.</description>
    </item> <item>
      <title>Urodynamic follow-up of experimental urethral obstruction in individual guinea pigs (Article)</title>
      <link>http://repub.eur.nl/res/pub/14363/</link>
      <pubDate>2001-12-18T00:00:00Z</pubDate>
      <description>It is unknown whether changes in bladder function due to urethral obstruction follow a specific sequence. To answer this, we adapted a small animal model to allow repeated complete pressure-flow studies, enabling individual follow-up of changes in bladder function on urethral obstruction. Obstruction was induced in guinea pigs by placing a silver ring around the urethra. Urodynamic studies were repeated under anesthesia with ketamine/xylazine. Bladders were filled and bladder pressure measured through a single suprapubic catheter. Urine flow rate was measured using an ultrasound probe around the penis. Accurate measurements of bladder pressure and urine flow rates were obtained at 1-week intervals for 11 weeks in individual guinea pigs. In the control animals, the urodynamic parameters did not show significant changes. In the obstructed group, urethral resistance (P(low,ave)) increased from 20 to 35 cm H(2)O after 4 weeks and remained at that level. The maximum flow rate (Q(max)) increased from 0.17 to 0.24 mL/s after 2 to 3 weeks. After this peak, it gradually decreased to lower than the starting value after 10 to 11 weeks. The pressure at maximum flow rate (p(Qmax)) increased from 24 to 47 cm H(2)O after 6 to 7 weeks and thereafter declined. During weeks 1 through 4 of obstruction, unstable contractions were seen. All animals followed a similar sequence of patterns but at variable rates. Our animal model allows complete urodynamic follow-up of individual animals with urethral obstruction. We observed a specific sequence of changes in urodynamic patterns and parameters of bladder function</description>
    </item> <item>
      <title>Measurement of urinary flow rate using ultrasound in young boys and infants (Article)</title>
      <link>http://repub.eur.nl/res/pub/14307/</link>
      <pubDate>2001-08-08T00:00:00Z</pubDate>
      <description>PURPOSE: We present a technique for measuring urinary flow rates with ultrasound in male infants and children. MATERIALS AND METHODS: Urinary flow rate was measured simultaneously by an ultrasound probe placed around the base of the penis and by a funnel with a rotating disk at the bottom in 30 boys with a mean age of 6.7 years (range 4.5 to 10.5), and by ultrasound in 8 infants with a mean age of 10 months (range 1 to 28). Voided volume was measured with a graded cylinder or calculated from the weight change of diapers in infants. Ultrasound and rotating disk maximum flow rates were calculated. The ultrasound signal was calibrated by comparing the collected voided volume to the area under the curve for that void. The volume calculated from the rotating disk flow rate curve was also compared with the collected volume. RESULTS: Both methods yielded similar flow curves. However, ultrasound maximum flow rate significantly exceeded rotating disk maximum flow rate (13 +/- 6 ml. per second, range 5 to 22 versus 10 +/- 4 ml. per second, range 4 to 21, t test p &lt;0.001). The underestimation of the flow rate by the rotating disk method may have been due to adherence of urine to the funnel wall. Rotating disk maximum flow rate was lower and voided volume was underestimated by up to 50% (average 15 +/- 2%) in 21 cases. Ultrasound maximum flow rate averaged 6 +/- 3 ml. per second (range 3 to 11.6 [oldest infant]) in the 8 infants. CONCLUSIONS: Urinary flow rates can be measured accurately using ultrasound in boys who produce small volumes and/or who are not toilet trained and also in infants. In future studies ultrasound will be applied to subsets of male infants with bladder dysfunction</description>
    </item> <item>
      <title>Changes in bladder contractility and compliance due to urethral obstruction: a longitudinal followup of guinea pigs (Article)</title>
      <link>http://repub.eur.nl/res/pub/14249/</link>
      <pubDate>2000-08-25T00:00:00Z</pubDate>
      <description>PURPOSE: We established the longitudinal changes in bladder contractility and compliance as a result of urethral obstruction using a guinea pig model. MATERIALS AND METHODS: Obstruction was induced in guinea pigs by a silver ring around the urethra. Urodynamic studies were performed longitudinally in individual animals. Bladder contractility and compliance were calculated from the measured bladder pressure and urine flow rate. RESULTS: Bladder contractility developed in distinct phases. It reached a maximum 200% increase after an average of 3.25 weeks concomitant with an almost 2-fold increase in urethral resistance, remained 150% to 200% increased during weeks 4 to 7 and then decreased to starting levels again, while urethral resistance remained almost 2-fold increased. Bladder compliance decreased by 80% during the first 3 weeks and continued to decrease to 5% of its original value after 10 to 11 weeks. CONCLUSIONS: Our data indicate that as a result of obstruction bladder function passes through a specific sequence of stages, including first a compensatory increase in contractility, then a stabilization phase and finally a decompensation state. In contrast bladder compliance shows a continuous decrease. The data suggest that for assessing how far a bladder has deteriorated due to obstruction a combination of functional and structural data may be warranted</description>
    </item>
  </channel>
</rss>