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C J Partsch

Publications and source records attributed to C J Partsch.

At least 37 records · Page 2Linked to original sources

Growth retardation in Turner syndrome: aneuploidy, rather than specific gene loss, may explain growth failure.

The etiology of short stature (SST) in Turner syndrome (TS) is still a subject of speculation. A variety of hypotheses have been put forward, from SST as a result of increased intrauterine tissue pressure after fetal lymphedema to haploinsufficiency of a specific growth gene(s). These hypotheses have various statistical-auxological implications on the growth distribution in TS. Empirical research has provided no clear evidence for any of these theories, but the well known correlation between patients' and midparental height (MPH) could be established. The influence of undetected mosaic status has often been cited as a major problem in the investigation of growth in TS. However, an assessment of mosaic status (simultaneous analysis of karyotype and phenotype) and its effect on growth with inclusion of MPH has been not yet carried out for a large sample. The aim of this study was to evaluate growth and its complex relationship to mosaic status and MPH in TS. In a mixed cross-sectional and longitudinal study we retrospectively analyzed the auxological and clinical data of 447 patients with a pure loss of X-chromosomal material (n = 381 with 45,X0; n = 66 mosaics). The 447 patients were selected from a series of 609 consecutive patients with TS. To assess the effect of mosaic status on growth, we computed a bifactorial analysis of variance (phenotype, karyotype), including MPH as a covariate. In line with the mosaic hypothesis, we found a correlation between individual loss of X-chromosomal material and phenotypical expressivity. In contrast, no correlation was found with respect to growth. With respect to MPH, we found growth retardation (GR) even in those patients with "normal" height above the third percentile (-2 or more SD score). The interindividual variance of GR in TS (comparable to growth variance in the normal population) seems to be unrelated to other TS-specific factors (e.g. mosaic status or single gene loss). Instead, both interindividual variance and the global growth shift distribution are best explained by the presence of an unspecific aneuploidic effect. Furthermore, consideration of patient height in relation to MPH should lead to a better understanding of the nature of GR in TS than the commonly used, strictly qualitative definition of SST.

Adolescent↗

Long-term outcome after depot gonadotropin-releasing hormone agonist treatment of central precocious puberty: final height, body proportions, body composition, bone mineral density, and reproductive function.

A considerable number of patients with central precocious puberty (CPP) treated with depot GnRH agonists have reached final height (FH). The aim of this prospective, multicentric study was the evaluation of the benefits, side-effects, and long term outcome of depot GnRH agonist therapy. We investigated 50 young women (mean +/- SD age, 16.7+/-2.6 yr; range, 12.9-23.4 yr) at FH. They received depot triptorelin over a period of 4.4+/-2.1 yr (range, 1.0-9.7 yr). Target height (TH) and predicted adult height (PAH) at the start of treatment were 163.6+/-6.2 and 154.9+/-9.6 cm, respectively (P < 0.05). FH was 160.6+/-8.0 cm (FH vs. TH, P = NS; FH vs. PAH, P < 0.05). Young patients showed the highest height gain (FH minus initial PAH). Seventy-eight percent of all patients reached a FH within their TH range. Even in young patients and those with an unfavorable initial PAH below the TH range, 60% reached a FH within their individual TH range. Standardized bone mineral density and standardized bone mineral density SD score investigated by dual energy x-ray absorptiometry of the lumbar spine (L1-L4) were 1040.9+/-124.2 mg/cm2 and 0.0+/-1.0; those of the femoral neck were 902.2+/-115.4 mg/cm2 and 0.2+/-1.0, respectively. The SD score of the ratio of sitting height over lower leg length was normal (0.3+/-1.2). Body mass index SD scores at pretreatment, at the end of treatment, and at FH were not significantly different (2.0+/-2.0, 2.0+/-2.0, and 1.7+/-2.2, respectively). Menarche or remenarche started at age 12.3+/-1.4 yr (range, 9.3-15.8 yr) in all patients. In conclusion, long term depot GnRH agonist treatment of CPP girls preserved genetic height potential and improved FH significantly combined with normal body proportions. No negative effect on bone mineral density and reproductive function was seen. Treatment neither caused nor aggravated obesity.

Absorptiometry, Photon↗

Efficacy of the subcutaneous reformulated triptorelin depot in children with central precocious puberty.

The efficacy, safety and acceptance of newly formulated triptorelin s.c. (Decapeptyl Depot, DDsc) was compared to triptorelin i.m. (DDim) in seven children with central precocious puberty (CPP) in a prospective study. Both formulations were given for 6 months consecutively. During both treatment periods suppression of basal and gonadotropin-releasing hormone (GnRH)-stimulated levels of luteinizing hormone and follicle-stimulating hormone, suppression of sex steroids, arrest of the maturation of gonads and uterus, and slowing of bone maturation were achieved. The height standard deviation score for bone age increased significantly during DDsc treatment (-1.33+/-0.90 to 1.07+/-0.92, p < 0.05). The ratio bone age/chronological age decreased significantly during both treatment periods (1.25+/-0.24 to 1.20+/-0.23,p < 0.05, and 1.20+/-0.23 to 1.16+/-0.22, p < 0.05). With the injection of DDsc in the abdominal wall, a palpable, non-irritating resistance which gradually decreased in size occurred in one patient. With injection into the thigh no indurations were seen. No allergic reactions were encountered. Five of the patients considered DDsc therapy as more pleasant and described a definite decrease in fear of injections. All parents considered DDsc treatment as equal or better than DDim in respect to the suppression of their child' s puberty. It was concluded that DDsc is equipotent to DDim in the treatment of CPP. For the majority of patients DDsc was more acceptable than DDim. The thigh is recommended for the subcutaneous application of DD.

Child↗

A mutation in the first transmembrane domain of the lutropin receptor causes male precocious puberty.

We describe a patient with onset of puberty at the age of 5 yr. characterized by accelerated growth, enlargement of genitalia, pubarche, and serum hormone levels compatible with noncentral precocious puberty. Exon 11 of the LH receptor gene was amplified from genomic DNA by PCR and directly sequenced. We identified a heterozygous C to T base change at nucleotide position 1126, exchanging codon 373 from Ala to Val in the first transmembrane domain. The LH receptor sequence of the parents was normal. The mutated receptor displayed an up to 7.5-fold increase in basal cAMP production compared to that of the wild-type receptor in transiently transfected COS-7 cells. Treatment of the patient with ketoconazole resulted in inconsistent suppression of serum testosterone levels. At the age of 9.1 yr, central activation of the hypothalamic-pituitary-gonadal axis occurred. Additional treatment with a GnRH agonist led to complete suppression of testosterone secretion. This is the first description of constitutive activation of the LH receptor in the first transmembrane segment. It suggests the involvement of the first transmembrane helix in signal transduction and provides further insight into the structural organization of the seven transmembrane domains of the glycoprotein hormone receptor proteins.

Amino Acid Sequence↗

Congenital adrenal hypoplasia: clinical spectrum, experience with hormonal diagnosis, and report on new point mutations of the DAX-1 gene.

X-linked congenital adrenal hypoplasia (AHC) is a rare developmental disorder of the human adrenal cortex and is caused by deletion or mutation of the DAX-1 gene, a recently discovered member of the nuclear hormone receptor superfamily. Hypogonadotropic hypogonadism is frequently associated with AHC. AHC occurs as part of a contiguous gene syndrome together with glycerol kinase deficiency (GKD) and Duchenne's muscular dystrophy. The present series, collected over the past 2 decades, includes 18 AHC boys from 16 families: 4 with AHC, GKD, and Duchenne's muscular dystrophy; 2 with AHC and GKD; and 12 with AHC (5 young adults with hypogonadotropic hypogonadism). Most of the boys presented with salt wasting and hyperpigmentation during the neonatal period. Plasma steroid determinations performed in the first weeks of life often showed confusing results, probably caused by steroids produced in the neonates' persisting fetocortex. Aldosterone deficiency usually preceded cortisol deficiency, which explains why the patients more often presented with salt-wasting rather than with hypoglycemic symptoms. An ACTH test was often necessary to detect cortisol deficiency in the very young infants. In some patients, serial testing was necessary to establish the correct diagnosis. In 4 boys studied during the first 3 months after birth, we found pubertal LH, FSH, and testosterone plasma levels indicating postnatal transient activation of the hypothalamic-pituitary-gonadal axis as in normal boys. Previous studies have shown that the DAX-1 gene is deleted in the AHC patients with a contiguous gene syndrome and is mutated in nondeletion patients. Most of the point mutations identified in AHC patients were frameshift mutations and stop mutations. In the 15 patients available for molecular analysis of the DAX-1 gene, there were large deletions in 6 patients and point mutations in another 7 patients. All of the point mutations identified in the present study resulted in a nonfunctional truncated DAX-1 protein. Two brothers with primary adrenal insufficiency and a medical history that strongly suggested AHC had no mutation in the DAX-1 gene. Thus, additional, as yet unknown genes must play a part in normal adrenal cortical development.

Adrenal Insufficiency↗

Growth promotion and Turner-specific bone age after therapy with growth hormone and in combination with oxandrolone: when should therapy be started in Turner syndrome?

The aims of this comparative multicenter study of 67 girls with Turner syndrome (TS) on three different therapeutical regimens were, first, to evaluate the effect of either recombinant human growth hormone (GH) alone or in combination with the anabolic steroid oxandrolone (Oxa) on height velocity and on Turner-specific bone age (BA'TS) and, second, to estimate the gain in final height taking the age at the onset of treatment into account. The mean advancement of BA'TS in 2 years of treatment was 2.5 years/2 years in group 1 (low dose GH: 16 IU/m2/week), 2.8 years/2 years in group 2 (high dose GH: 28 IU/m2/week) and 3.3 years/2 years in group 3 (GH: 24 IU/m2/week + Oxa: 0.06 mg/kg/day) instead of the expected 2 years/2 years advancement in untreated girls with TS. On all treatment regimens the advancement of BA'TS was more pronounced in the younger girls. In many girls with a BA'TS below 9 years at the onset of treatment the increase in height did not outweigh the advancement in BA'TS, suggesting that starting growth-promoting treatment before 9 years would not be the best way to improve final height. In our opinion, the optimal age for starting growth-promoting therapy is at 9 years. A start at a younger age might have no advantage in regard of an ultimate gain in final height. On the other hand, therapy should not be delayed much after the age of 9 years giving the girls with TS the possibility to catch up substantially before estrogen treatment is initiated.

Age Determination by Skeleton↗

Incidence and spectrum of renal abnormalities in Williams-Beuren syndrome.

Kidneys and urinary tract were examined systematically by ultrasonography in 130 patients with Williams-Beuren syndrome (59 females, median age 5.5 years; 71 males, median age 6.4 years). In addition, serum creatinine was determined and an analysis was performed. Creatinine clearance was available in 79 patients. Renal angiographic examinations were done in 18 patients, 8 of whom had renal artery narrowing (44%). The incidence of renal anomalies in Williams-Beuren syndrome was 17.7% vs. around 1.5% in the normal population (P < 0.0003). The spectrum of these anomalies ranged from minor anomalies such as bladder diverticula to more severe malformations such as renal aplasia or hypoplasia (in 5 of 130 patients). In nine patients a duplicated kidney was found. A decreased creatinine clearance (two patients), recurrent symptomatic urinary tract infections (four patients), and hypertension were uncommon. Nephrocalcinosis was not found in our patients. Our data demonstrate that the risk of a structural abnormality of the kidneys and the urinary tract is increased 12- to 36-fold in Williams-Beuren syndrome compared to the normal population. Ultrasound screening of the renal system should be part of the first evaluation of WBS patients.

Adolescent↗

Prenatal diagnosis of congenital adrenal hypoplasia.

Congenital adrenal hypoplasia is a rare disorder and one of the possible causes of low maternal plasma and/or urine estriol during pregnancy. We studied 2 cases pre- and postnatally. Dehydroepiandrosteronesulfate (DHAS) and estriol (E3) studied longitudinally in maternal plasma were at or below the lower limit of the normal range. Prior to substitution treatment, an ACTH test revealed low plasma levels of aldosterone, cortisol and all their precursors, with no rise after ACTH. ACTH plasma levels were elevated. It is possible to detect congenital adrenal hypoplasia prenatally in families at risk by repeated measurements of DHAS and estriol in maternal plasma during pregnancy.

Adrenal Insufficiency↗

Characteristics of pulsatile and circadian prolactin release and its variability in men.

In order to investigate the intra- and interindividual variability of spontaneous prolactin (PRL) secretion, 24 h blood sampling at 10 min intervals was performed in ten healthy young men (age 19 to 25 yrs) on three occasions (intervals 2 weeks and 3 months). Plasma PRL concentrations were determined in duplicate by immunoradiometric assay. Peak detection was carried out with the PULSAR program. The circadian rhythm was analyzed by a complex cosinor method combining fundamental (24 h), 1st harmonic (12 h), and 2nd harmonic (6 h) frequencies. The original data was well represented by this calculation as shown by mean (+/- SD) correlation coefficients of 0.84 +/- 0.08. Mean and integrated PRL concentrations showed the lowest intraindividual variability (range 2.8 to 19.6%) of all parameters tested. For the number of peaks per 24 h, a median intraindividual variability of 24.2% (range 6.9 to 50%) was seen. In general, intraindividual variability of parameters of pulsatile PRL release was lower than the variability between subjects. The complex cosinor analysis revealed a bimodal pattern of PRL secretion in most profiles. Acrophases (times of highest PRL levels) were found between 0040 and 1000 h, nadirs between 0030 and 2300 h. The amplitude of the circadian rhythm (Max-Min) ranged from 3.8 to 16.9 ng/ml. The time lag between onset of sleep and acrophase was variable (1.75 to 7.38 hrs). Variability of nadir, minimal and maximal PRL, amplitude, and minimal PRL as percent of the mesor was significantly lower within individuals than between subjects (p < 0.02). During sleep, peak heights and peak amplitudes were significantly higher than during waking periods (p < 0.004). No statistically significant differences were found in the distribution of relative frequencies of peak number, peak amplitudes and peak heights between the three series of profiles. The distribution of peak heights was compatible with a normal distribution. In conclusion, it was shown that the circadian rhythm of PRL secretion in normal men can be analysed accurately and reliably with the complex cosinor method, which is relatively easy to perform and yields results comparable to those obtained by much more complicated programs.(ABSTRACT TRUNCATED AT 400 WORDS)

Activity Cycles↗

Circadian and ultradian variations of pituitary and pineal hormones in normal men: evidence for a link between melatonin, gonadotropin, and prolactin secretion.

The study was performed to investigate the physiological relationship between the pineal hormone melatonin and pituitary functions in normal men. Series of blood samples were obtained at 10-min intervals for 24-hr periods from 10 male volunteers (age 19-25 years). Samplings were repeated after 2 weeks and 3 months. Serum levels of melatonin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and testosterone (T) were estimated by immunoassay methods (LH, PRL, every sample; melatonin, every 30 min; T, every 4 hrs; FSH once for each session). Diurnal characteristics of PRL and melatonin profiles were estimated by complex cosinor analysis, while short-term pulsatility of LH and PRL secretion was analyzed by the PULSAR algorithm. Data were correlated by linear regression analysis. The combined information of all three sampling sessions revealed significant negative correlations between the following parameters (N = 10): Amplitude (Ampl) melatonin and Ampl PRL: r = -0.727, P < 0.02; Ampl melatonin and maximal (Max) PRL values: r = -0.73, P < 0.02; Max melatonin and Max PRL: r = -0.725, P < 0.02; area under the curve (AUC) melatonin and Ampl PRL: r = -0.637, P < 0.05; AUC melatonin and Max PRL: r = -0.640; P < 0.05; duration (Dur) of melatonin synthesis and Ampl PRL: r = -0.685, P < 0.03; Dur melatonin and Max PRL: r = -0.676, P < 0.04; Dur melatonin and FSH levels: r = -0.663, P < 0.04; AUC melatonin and LH mean concentration: r = -0.732, P < 0.02; Max melatonin and LH mean concentration: r = -0.657, P < 0.04.(ABSTRACT TRUNCATED AT 250 WORDS)

Activity Cycles↗

Multisteroid analysis in children with terminal aldosterone biosynthesis defects.

Aldosterone (Aldo), the most potent mineralocorticoid, is synthesized in the adrenal zona glomerulosa, requiring 11 beta-hydroxylation of 11-deoxycorticosterone (DOC) to form corticosterone (B), hydroxylation at position C18 to form 18-hydroxycorticosterone (18-OHB), and finally oxidation at position C18. There is a single cytochrome P450 enzyme (P450aldo) catalyzing all three reactions in the zona glomerulosa. The gene encoding for this enzyme is termed CYP11B2. There are two inborn errors of terminal aldosterone biosynthesis characterized by overproduction of B and deficient synthesis of Aldo. Corticosterone methyl oxidase deficiency type I (CMO-I) is characterized by decreased production of 18-OHB, whereas CMO-II is characterized by overproduction of 18-OHB and an elevated plasma ratio of 18-OHB to Aldo. Both disorders have an autosomal recessive inheritance and are rare causes of salt-wasting and failure to thrive in early infancy. In the last 10 yr, we diagnosed 16 infants with CMO deficiencies by simultaneous multisteroid analysis in a small plasma sample (RIA after extraction and automated high performance gel chromatography). All patients presented with severe failure to thrive in the first 3 months of life, associated with severe hyponatremia, hyperkalemia, and increased PRA. Basal Aldo levels were decreased (range, 0.055-0.11 nmol/L), whereas B was elevated (range, 19-154 nmol/L). Plasma 18-OHB, ranging from 0.063-0.44 nmol/L, was decreased or in the lower normal range in seven patients, whereas the other seven patients had elevated 18-OHB levels (range, 12.1-57.7 nmol/L). 18-OH-DOC (range, 0.81-7.8 nmol/L) and DOC (range, 0.7-9.53 nmol/L) levels were elevated in all patients. In seven patients, we found an elevated ratio of 18-OHB/Aldo (range, 286-900) and a low ratio of B/18-OHB (range, 1.1-5.8), whereas seven other patients had a low 18-OHB/Aldo ratio (range, 1.1-6.95) and a high B/18-OHB ratio (range, 41-1360). These findings confirmed the diagnosis of CMO-I in seven patients (low 18-OHB, 18-OHB/Aldo ratio < 10, and B/18-OHB ratio > 40) and the diagnosis of CMO-II in seven other patients (high 18-OHB, 18-OHB/Aldo ratio > 100, and B/18-OHB ratio < 10), whereas 18-OHB could not be determined in two patients. The B/18-OHB ratio appears particularly useful in CMO cases with undetectably low Aldo plasma levels and uncalculable 18-OHB/Aldo ratios. In conclusion, the simultaneous multisteroid determination method allows the precise differentiation of CMO-I and CMO-II in a small plasma sample during early infancy.

Aldosterone↗

Injectable testosterone undecanoate has more favourable pharmacokinetics and pharmacodynamics than testosterone enanthate.

Testosterone preparations producing constant physiological testosterone serum levels are desirable for long-term treatment of androgen deficiency. However, all injectable testosterone esters used clinically for substitution of male hypogonadism are characterized by unfavourable pharmacokinetics. We therefore tested two groups of five long-term orchidectomized cynomolgus monkeys (Macaca fascicularis), which received a single intramuscular injection of 10 mg/kg body weight of an injectable testosterone undecanoate (TU) preparation or testosterone enanthate (TE) in a preclinical study to assess the pharmacokinetic and pharmacodynamic characteristics of TU in comparison to TE. The dose was equivalent to 6.3 and 7.2 mg of pure testosterone per kilogram body weight in the TU and TE group, respectively. Following injection of TU, mean serum testosterone rose to 58 +/- 18 nmol/l on day 1 and remained at moderately supraphysiological levels of 40-68 nmol/l for 45 days. Thereafter, testosterone levels were maintained in the normal range of intact monkeys for another 56 days. The TE injection resulted in highly supraphysiological levels of 100-177 nmol/l from immediately after the injection to day 5. A rapid decline followed and testosterone levels reached the lower limit of normal after 31 days. Serum testosterone levels were significantly higher in the TE-than in the TU-treated animals on days 0.5-7 (p < 0.05). Significantly lower testosterone levels were seen in the TE than in the TU group on days 16, 22, 25 and 31 (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Head circumference of children with Williams-Beuren syndrome.

Head circumference is considered an important parameter of brain growth and development. Syndrome-specific standards for head circumference in Williams-Beuren syndrome (WBS) are not available to date, although mental retardation is a leading manifestation in the syndrome. Therefore, we investigated head growth in 63 girls (251 measurements) and 88 boys (298 measurements) with WBS between birth and adulthood. Most measurements in both sexes were from the first 4 years of life (n = 162 in girls and n = 189 in boys). Mean (+/- SD) head circumference at birth was 33.39 +/- 1.38 cm and 34.02 +/- 1.44 cm for term girls and boys, respectively. Although head growth in WBS girls and boys was at a slower velocity, the pattern of head circumference was similar to that in the normal population. After the age of 3 months, head circumference started to fall below the normal mean in girls (0.5-2 cm). In boys, mean head circumference was below the normal mean already at 1 month of age (2 cm). The deficit increased to 3 cm from 6 months to 4 years. Adult OFC was 52.85 +/- 1.75 cm (n = 16) compared to 55.70 +/- 1.83 cm (n = 46; P < 0.00001) in WBS women and 55.51 +/- 1.68 cm (n = 30) compared to 57.87 +/- 1.29 cm (n = 31; P < 0.00001) in WBS men. During development, microcephaly is only seen in about one third of WBS patients.

Abnormalities, Multiple↗

Natural history of body mass index in Williams-Beuren syndrome.

Body mass index (BMI) is a useful tool for the investigation of obesity or underweight. It follows a typical pattern throughout childhood. During the first few years of life underweight due to feeding problems and gastrointestinal disturbances is considered a common sign in Williams-Beuren syndrome (WBS), whereas obesity is frequently reported in WBS adults. Systematic studies on weight gain and body mass index in WBS do not exist. Therefore, we studied weight gain relative to height expressed as BMI in 82 WBS girls (459 measurements of weight and height) and in 104 WBS boys (562 measurements). At birth BMI was significant lower in WBS than in normal infants in both sexes (P < 0.0001). During the first months of life, mean BMI showed a catch-up from the 3rd to the 10th-50th centiles in WBS infants relative to the normal standards. The further course of BMI was almost parallel to normal development. In addition, a gradual relative increase to the 50th centile of normal was seen in both sexes. In conclusion, weight gain during the first year of life was sufficient. Feeding and gastrointestinal problems seem not to have a severe impact on weight gain in infancy. Until adulthood weight relative to height continuously reached the 50th centile of normal. Thus, obesity is not a common finding in young adults with WBS. The results of this study may serve as a disease-specific reference of BMI development in WBS patients.

Abnormalities, Multiple↗