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Featured researches published by Stenvert L. S. Drop.


Archives of Sexual Behavior | 1998

Long-term psychological evaluation of intersex children

Froukje Slijper; Stenvert L. S. Drop

Treatment of psychological problems of 59 children with a physical intersex condition is described. The group consisted of 18 female pseudohermaphrodites with congenital adrenal hyperplasia (CAH), 20 male pseudohermaphrodites and 2 true hermaphrodites born with ambiguous external genitalia assigned the female sex (ambiguous girls), 14 male pseudohermaphrodites born with completely female external genitalia and assigned the female sex (completely female group), and 5 male pseudohermaphrodites born with ambiguous external genitalia and assigned the male sex. Despite the sex assignment, genital organ correction soon after birth, psychological counseling of parents and intensive psychotherapy of the children, general psychopathology developed equally in all 4 groups (39% of total group). Although 87% of the girls with a physical intersex condition developed in line with the assigned sex, 13% developed a gender identity disorder though only 1 girl (2%) failed to accept the assigned sex. Gender identity disorder and deviant gender role were in evidence only in girls with CAH and girls of the ambiguous group. Biological and social factors seem responsible for the development of gender identity disorder, such as pre- and postnatal hormonal influences on the brain enabling deviant gender role behavior to develop, and an inability on the part of parents to accept the sex assignment. A reconsideration of the sex assignment in male pseudohermaphrodites and true hermaphrodites born with ambiguous external genitalia is discussed.


Diabetes | 2006

Heterozygosity for a POMC-Null Mutation and Increased Obesity Risk in Humans

I. Sadaf Farooqi; Stenvert L. S. Drop; Agnes Clements; Julia M. Keogh; Joanna M. Biernacka; Sarah Lowenbein; Benjamin G. Challis; Stephen O’Rahilly

Congenital deficiency of proopiomelanocortin (POMC) results in a syndrome of hypoadrenalism, severe obesity, and altered skin and hair pigmentation. The concept that subtle variation in POMC expression and/or function might contribute to common obesity is suggested by studies reporting linkage of obesity-related traits to a locus on chromosome 2p22 encompassing the POMC gene. We identified a novel homozygous frameshift (C6906del) mutation in POMC in a child of Turkish origin with severe obesity and hypoadrenalism. This mutation would be predicted to lead to the loss of all POMC-derived peptides. The availability of a large extended pedigree provided the opportunity to address whether loss of one copy of the POMC gene was sufficient to alter obesity risk. Twelve relatives were heterozygous for the mutation and 7 were wild type. Of the heterozygotes, 11 of 12 heterozygotes were obese or overweight compared with only 1 of 7 of the wild-type relatives. The mean BMI SD score was 1.7 ± 0.5 in heterozygotes and 0.4 ± 0.4 in the wild-type relatives. Parametric linkage analysis of the trait “overweight” provided statistically significant evidence of linkage with this locus, with a maximum “location score” (comparable with multipoint logarithm of odds scores) of 3.191. We conclude that loss of one copy of the POMC gene predisposes to obesity in humans. Thus, genetic variants having relatively subtle effects on POMC expression and function could influence susceptibility to obesity.


Pediatrics | 2006

Summary of Consensus Statement on Intersex Disorders and Their Management

Christopher P. Houk; Ieuan A. Hughes; S. Faisal Ahmed; Peter A. Lee; Olaf Hiort; Eric Vilain; Melissa Hines; Sheri A. Berenbaum; Ken Copeland; Patricia A. Donohoue; Laurence S. Baskin; Pierre Mouriquand; Polly Carmichael; Stenvert L. S. Drop; Garry L. Warne; John C. Achermann; Erica A. Eugster; Vincent R. Harley; Yves Morel; Robert Rapaport; Jean D. Wilson; Peggy T. Cohen-Kettenis; Jay N. Giedd; Anna Nordenström; William G. Reiner; Emilie F. Rissman; Sylvano Bertelloni; Felix A. Conte; Claude J. Migeon; Chris Driver

Advances in understanding of genetic control of sexual determination and differentiation, improvements in diagnostic testing and surgical genital repair, and the persistent controversies inherent to clinical management were all compelling factors that led to the organization of an international consensus conference. The goals were to acknowledge and discuss the more controversial issues in intersex management, provide management guidelines for intersex patients, and identify and prioritize questions that need additional investigation. This is a summary statement. Advances in molecular genetic causes of abnormal sexual development and heightened awareness of the ethical and patient-advocacy issues mandate reexamination of existing nomenclature for patients with intersex.1 Terminology such as “pseudohermaphroditism” is controversial, potentially pejorative to patients,2 and inherently confusing. Therefore, the term “disorders of sex development” (DSD) is proposed to indicate congenital conditions with atypical development of chromosomal, gonadal, or anatomic sex. Additional rationale for new classification is the need for modern categorization to integrate the modern molecular genetic aspects, to maximize precision when applying definitions and diagnostic labels,3 and to meet the need for psychologically sensitive yet descriptive medical terminology. Nomenclature should be flexible enough to incorporate new information, robust enough to maintain a consistent framework, use descriptive terms, reflect genetic etiology, accommodate phenotypic variation spectrum, and be useful for clinicians, scientists, patients, and families. Hence, we propose a new classification (see “Consensus Statement on Management of Intersex Disorders”4 in this months issue of Pediatrics Electronic Edition ). Three traditionally conceptualized domains of psychosexual development are gender identity (ones self-representation [ie, male or female]), gender role (sexually dimorphic behaviors within the general population, such as toy preferences, aggression, and spatial ability), and sexual orientation (direction[s] of erotic interest). Gender dissatisfaction denotes unhappiness with assigned sex and may result in gender self-reassignment. Psychosexual developmental factors relate to parental psychopathology, parent-child … Address correspondence to Peter A. Lee, MD, PhD, Department of Pediatrics, MC-H085, Penn State College of Medicine, Milton S. Hershey Medical Center, Box 850, 500 University Dr, Hershey, PA 17033-0850. E-mail: plee{at}psu.edu


The Lancet | 1994

Growth hormone treatment in growth-retarded adolescents after renal transplant

Anita Hokken-Koelega; S.M.P.F. de Munck Keizer-Schrama; Stenvert L. S. Drop; E.D. Wolff; T. Stijnen; M. A. J. de Ridder; M. C. J. W. de Jong; R.A. Donckerwolcke; Jaap W. Groothoff; Werner F. Blum

Abstract Growth failure is a psychosocial problem for many patients who have undergone renal transplantation. 18 adolescents (mean age 15 6, range 11·3-19 5) with severe growth retardation after renal transplantation were treated with biosynthetic growth hormone (GH) for 2 years. All received prednisone, administered daily or on alternate days, with azathioprine and/or cyclosporin A. 16 were blindly assigned to one of two GH doses (4 vs 8 IU per m 2 per day). Growth, bone maturation, renal graft function, plasma insulin-like growth factors, serum binding proteins, and other biochemical parameters were checked regularly. Glomerular filtration rate and effective renal plasma flow were tested with 125 I-Thalamate and 131 I-Hippuran. Data on growth and glomerular filtration rate during GH treatment were also compared with those of matched non-GH-treated controls. Mean (standard deviation) increment in height after 2 years of GH was 15·7 (5·1) cm, significantly greater (p 25% reduction in glomerular filtration rate over 2 years was not significantly higher in GH-treated patients than in non-GH-treated controls (39% vs 32%, p=0·97). Although a few patients had deterioration of graft function, we could not find a relation with GH treatment. Our results show that sustained improvement of height can be achieved with GH in severely growth-retarded adolescents after renal transplantation.


Molecular and Cellular Endocrinology | 1994

cDNA cloning and mRNA expression of the six mouse insulin-like growth factor binding proteins

Alwin Schuller; Cora Groffen; J.W. van Neck; E.C. Zwarthoff; Stenvert L. S. Drop

The insulin-like growth factor binding proteins (IGFBPs) comprise a family of six distinct proteins which modulate insulin-like growth factor action. We have isolated cDNAs encoding the six mouse IGFBPs (mIGFBPs). In addition, we studied the mRNA expression of the six mIGFBPs during development and in various adult tissues. Our results show that each of the six mIGFBPs is highly homologous to their human and rat counterparts, whereas only the N and C terminal ends are conserved between the six mIGFBPs. Northern blotting revealed that mIGFBP-2, -3, -4 and -5 genes are already expressed at gestational day 11.5, suggesting a role for these mIGFBPs in embryonal development. In liver, a peak of mIGFBP-1 mRNA expression was found around birth, suggesting a function for mIGFBP-1 in the newborn mouse. Finally, tissue-specific expression of the six mouse IGFBP genes was observed in adult tissues suggesting different roles or modes of actions in adult life.


Best Practice & Research Clinical Endocrinology & Metabolism | 2010

Gonadal tumours and DSD

Leendert Looijenga; Remko Hersmus; Bertie de Leeuw; Hans Stoop; Martine Cools; J. Wolter Oosterhuis; Stenvert L. S. Drop; Katja P. Wolffenbuttel

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.


The Journal of Clinical Endocrinology and Metabolism | 2010

Isolated 17,20-Lyase Deficiency due to the Cytochrome b5 Mutation W27X

Renée C. Kok; Marianna A. Timmerman; Katja P. Wolffenbuttel; Stenvert L. S. Drop; Frank H. de Jong

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 b(5) (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.


Molecular and Cellular Endocrinology | 1997

Gene expression of the insulin-like growth factor system during mouse kidney development

Dicky J. Lindenbergh-Kortleve; Roberto R. Rosato; Johan W. van Neck; Jeroen Nauta; Marjolein van Kleffens; Cora Groffen; Ellen C. Zwarthoff; Stenvert L. S. Drop

Expression of the insulin-like growth factor (IGF) system was investigated in mouse renal development and physiology, using non radioactive in situ hybridization and quantitative RT-PCR. IGF-I mRNA levels increased after birth and were confined to distal tubules and peritubular capillaries in the outer medulla. IGF-II mRNA levels were high in developing kidneys and peaked after birth. The type I receptor mRNA expression pattern mostly parallelled those of IGF-I and IGF-II. The IGF binding proteins (IGFBPs) showed weak mRNA expression for IGFBP-1 and -6. High fetal mRNA levels were measured for IGFBP-2, showing a similar profile in time as observed for IGF-II. Low fetal IGFBP-3 and -5 mRNA levels increased after birth. IGFBP-2, -4 and -5 mRNA expression was localized to differentiating cells. In the mature kidney predominant expression was confined to proximal tubules (IGFBP-4), thin limbs of Henles Loop (IGFBP-2), glomerular mesangial cells (IGFBP-5) and peritubular capillaries of the medulla (IGFBP-5). IGFBP-3 mRNA was exclusively expressed in endothelial cells of the renal capillary system. Distinct mRNA expression for each member of the IGF system may point to specific roles in development and physiology of the mouse kidney.


Hormone Research in Paediatrics | 2002

Early Puberty in Adopted Children

Dick Mul; Wilma Oostdijk; Stenvert L. S. Drop

Early puberty is frequently observed in adopted children. In various studies, early puberty has been associated with decreased final height. In Europe, studies were undertaken to treat early puberty in adopted children with GnRH agonist. This article reviews the current understanding of early puberty in adopted children, including prevalence, background and treatment options. Data from the European studies are briefly described. Besides auxological aspects, psychological items are addressed as well. Studies on the psychological effect of early puberty in adopted children are reported. Future issues include further study in the mechanism of early puberty in adopted children, evaluation of final height results of the growth studies and quality of life assessments in this specific group of children.


Pediatric Research | 2001

Bone mineral density assessed by phalangeal radiographic absorptiometry before and during long-term growth hormone treatment in girls with Turner's syndrome participating in a randomized dose-response study

Theo C. J. Sas; Sabine M.P.F. de Muinck Keizer-Schrama; Theo Stijnen; Arne van Teunenbroek; Wibeke van Leeuwen; Anjalie Asarfi; Rick R. van Rijn; Stenvert L. S. Drop

To assess bone mineral density (BMD) in girls with Turners syndrome before and during long-term treatment with GH, longitudinal measurements using phalangeal radiographic absorptiometry were performed in 68 girls with Turners syndrome. These previously untreated girls, age 2–11 y, participating in a randomized, dose-response trial, were randomly assigned to one of three GH dosage groups: group A, 4 IU/m2/d (≈0.045 mg/kg/d); group B, first year 4 IU/m2/d, thereafter 6 IU/m2/d (≈0.0675 mg/kg/d); or group C, first year 4 IU/m2/d, second year 6 IU/m2/d, thereafter 8 IU/m2/d (≈0.090 mg/kg/d). In the first 4 y of GH treatment, no estrogens for pubertal induction were prescribed to the girls. Thereafter, girls started with 17β-estradiol (5 μg/kg body weight/d, orally) when they had reached the age of 12 y. BMD results were adjusted for bone age and sex, and expressed as SD scores using reference values of healthy Dutch girls. At baseline, almost every individual BMD value of bone consisting predominantly of cortical bone, as well as that of bone consisting predominantly of trabecular bone, was within the normal range of healthy girls and the SD scores were not significantly different from zero [mean (SE) 0.38 (0.22) and −0.04 (0.13)]. During 7 y of GH treatment, BMD SD scores showed a significant increase to values significantly higher than zero [mean (SE) 0.87 (0.15) and 0.95 (0.14)]. The increment in BMD SD score of bone consisting predominantly of cortical bone was significantly higher in group C compared with that of the other two GH dosage groups. The pretreatment bone age was significantly negatively related to the increment in BMD SD score. We found no significant influence of spontaneous puberty or the use of low-dose estrogens in the last 3 y of the study period on the increment in BMD SD score during 7 y of GH treatment. In conclusion, most untreated young girls with Turners syndrome have a normal volumetric BMD. During 7 y of GH treatment with 4, 6, or 8 IU/m2/d, the BMD SD score increased significantly.

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Leendert Looijenga

Erasmus University Rotterdam

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Martine Cools

Ghent University Hospital

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Arianne B. Dessens

Erasmus University Rotterdam

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Remko Hersmus

Erasmus University Rotterdam

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Hans Stoop

Erasmus University Rotterdam

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J. Wolter Oosterhuis

Erasmus University Rotterdam

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Frank H. de Jong

Erasmus University Rotterdam

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