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B Stoffel-Wagner

Publications and source records attributed to B Stoffel-Wagner.

49 records · Page 3Linked to original sources
PubMed1998

Expression of 5alpha-reductase in the human temporal lobe of children and adults.

Androgens exert important biological effects on the brain, and 5alpha-reductase plays a crucial role in androgen metabolism. Therefore, we investigated the expression of the two isozymes of 5alpha-reductase in the human temporal lobe to determine the predominant isoform and to elucidate the existence of possible sex differences and differences between children and adults. We studied biopsy materials from the temporal lobe of 34 women, 32 men, and 12 children. Quantification of 5alpha-reductase 1 and 2 messenger ribonucleic acid (mRNA) was achieved by competitive RT-PCR. 5Alpha-reductase activity was determined in tissue homogenates using [1,2-3H]androstenedione as the substrate. Only 5alpha-reductase 1 mRNA was expressed in human temporal lobe tissue; 5alpha-reductase 2 mRNA was not expressed. 5Alpha-reductase 1 mRNA concentrations did not differ significantly in the cerebral cortex of women [25.9+/-7.9 arbitrary units (aU); mean +/-SEM] and men (20.4+/-2.8 aU) or in the cerebral cortex (23.3+/-4.4 aU) and the subcortical white matter of adults (32.6+/-5.6 aU), but they were significantly higher in the cerebral cortex of adults than in that of children (6.4+/-2.3 aU; P < 0.005). The apparent Km of 5alpha-reduction did not show significant differences between the two sexes. In conclusion, 5alpha-reductase 1 mRNA is expressed in the temporal lobe of children and adults, but 5alpha-reductase 2 mRNA is not. 5Alpha-reductase 1 mRNA concentrations did not differ significantly in the sexes, but they were significantly higher in specimens of adults than in those of children.

Adult↗
PubMed1997

An optimized protocol for mRNA quantification using nested competitive RT-PCR.

Nested competitive reverse transcription polymerase chain reaction is an effective tool for the quantification of low level expressed mRNAs. Competitive RNA standards with small deletions allow the use cRT-PCR. The sensitivity is further increased by the utilization of nested PCR protocols. To optimize quantification of low abundance mRNAs we modified established protocols for use of automated labstations and semiautomated sequencers. In placental tissue, known for a very high CYP19 (P450AROM, aromatase) expression, cRT-PCR and nested cRT-PCR yielded virtually identical results which could be confirmed by Northern blotting. CYP19 mRNA in breast tumour tissue ranged below detection levels for Northern blotting; however, using our modified assay CYP19 showed 1.5 to 15 fold higher expression levels than in normal glandular breast tissue. Our approach proved to be useful for the quantification of a gene with low level expression. The employment of labstations and semiautomated sequencers allows rapid analysis of large sample numbers.

Aromatase↗
PubMed1997

[Initial symptoms and anamnestic time in 517 patients with pituitary adenoma].

OBJECTIVE: To find out whether recent techniques of investigating hypophyseal adenoma (computed tomography, magnetic resonance imaging and hormonal measurements) have brought about earlier diagnosis. PATIENTS AND METHODS: The time of onset of first symptoms and the duration from first symptoms to diagnosis (anamnestic time) were determined retrospectively from clinical, endocrinological, ophthalmological and localizing data on 517 patients (311 women, 206 men) with hypophyseal adenoma. RESULTS: The most common initial symptom was oligo- or amenorrhoea, in 57.9% of women, and disturbed libido or potency in 38.5% of men. Next most common were visual field deficits (women: 11.6%, men: 26.7%), signs of acromegaly (women: 11.3%, men 18.2%) and headaches (women: 11.3%, men 15.5%). The median anamnestic time in women, 3.0 years, was significantly longer than the 2.3 years in men (P < 0.001). In hormonally inactive adenoma the corresponding times were 2.0 years in women and 1.0 year in men; in prolactinoma 4.2 years and 2.0 years; in growth-hormone secreting adenoma 5.0 years and 5.5; and in ACTH-secreting adenoma 5.0 years and 1.0 year. CONCLUSIONS: Although diagnostic techniques have greatly improved, the anamnestic time for hypophyseal adenoma is not shorter than in earlier studies. This findings underlines the need for clearly directed history-taking and for good training in endocrinology.

Acromegaly↗
PubMed1997

Renal functional reserve and nitric oxide in patients with compensated liver cirrhosis.

To investigate the role of nitric oxide (NO) with respect to kidney function and liver cirrhosis, we evaluated renal function, as well as cyclic guanosine monophosphate (cGMP) and NOx (nitrite/nitrate [NO3-/NO2-]) as indirect markers of NO formation in plasma and urine at rest and during amino acid (aa)-induced glomerular hyperfiltration in patients with Child A liver cirrhosis and portal hypertension (n = 12), and in healthy controls (n = 10). Baseline filtration rate (GFR) and effective renal plasma flow (ERPF) were significantly lower in patients with cirrhosis than in controls (GFR: mean 88 +/- SD 16 mL/min vs. 106 +/- 15 mL/min, P = .01, ERPF: 477 +/- 93 vs. 561 +/- 72 mL/min, P = .002). In both groups amino acid (aa) infusion increased GFR, ERPF, as well as cGMP and urinary NOx. Changes in GFR were similar in cirrhotic patients and controls (28.3% +/- 14% in cirrhotics and 26% +/- 11% in controls), but the degree of aa-induced changes in ERPF was more marked in patients with liver cirrhosis (31.8% +/- 17% vs. 18.6% +/- 12%, P = .02). Plasma levels of NOx and cGMP were similar in either group at baseline and during aa infusion, whereas NOx and cGMP excretion in cirrhotics was constantly 14% to 24% lower than in the control group. We conclude that patients with compensated liver cirrhosis and portal hypertension already have an impaired kidney function. In addition our data suggest a cirrhosis-related dissociation between ERPF and GFR during aa stimulation. Further studies are warranted to find out whether a local imbalance between vasoconstrictors and vasodilators, e.g., decreased local NO formation, plays a key role for this phenomenon.

Adult↗
PubMed1997

A comparison of different methods for diagnosing acromegaly.

OBJECTIVE: The present study was designed to assess the diagnostic value of different single measurements in comparison to the classic time-consuming method, the oral glucose tolerance test (OGTT), in acromegaly. DESIGN, PATIENTS AND MEASUREMENTS: IGF-I, free IGF-I, 24-hour-urinary GH (uGH), serum IGFBP-3 and 24-hour-urinary IGFBP-3 (uIGFBP-3) were measured in 12 patients with untreated active acromegaly, in 29 patients who had been treated but were not cured, in 13 patients with cured acromegaly and in 14 healthy control subjects, and compared with the results of the OGTT. RESULTS: In all patients with active acromegaly, whether they had been treated or not, nadir GH in OGTT was > 3 mU/l, whereas nadir GH was < 1.8 mU/l in the cured patients and the control subjects. In patients with untreated active acromegaly IGF-I, free IGF-I, uGH and IGFBP-3, but not uIGFBP-3, were significantly higher than in healthy individuals (P < 0.0001). Only IGF-I values did not overlap with the control group. In those patients with acromegaly who had been treated but not cured these parameters overlapped with the control group. In patients with acromegaly there was a significant correlation between nadir GH levels in OGTT and IGF-I (r = 0.71), free IGF-I (r = 0.76), IGFBP-3 (t = 0.73) and uGH (r = 0.81) (P < 0.0001), but no correlation with uIGFBP-3. CONCLUSIONS: Only be means of the OGTT could patients with active acromegaly be completely distinguished from the control subjects and from cured patients. IGF-I, free IGF-I, IGFBP-3 and uGH were useful in the diagnosis of acromegaly, but of limited value in the follow-up of acromegalic patients after treatment. The determination of free IGF-I, which has yet not been investigated in acromegaly, offered no advantage over that of total IGF-I and IGFBP-3; uIGFBP-3 was not useful in the diagnosis of acromegaly.

Acromegaly↗
PubMed1997

Gonadal function of patients treated with cisplatin based chemotherapy for germ cell cancer.

PURPOSE: The cure rate of patients with germ cell cancer of the testis has considerably improved since the introduction of cisplatin based chemotherapy. Because these patients are in their reproductive years and because some of them will be infertile after treatment, the effects of cytotoxic treatment on gonadal function are investigated by hormonal evaluations. MATERIALS AND METHODS: In a transversal trial, luteinizing hormone, follicle-stimulating hormone and testosterone were determined radioimmunologically in serum samples of 232 patients with germ cell tumors after unilateral orchiectomy (patient age 18 to 64 years) up to 153 months after chemotherapy. Additionally, 51 of these patients were investigated in a longitudinal trial before and up to 5 years after chemotherapy. All patients received at least 2 courses of different cisplatin based chemotherapy regimens: cisplatin/vinblastine/bleomycin, cisplatin/vinblastine/bleomycin/ifosfamide, cisplatin/etoposide/bleomycin, cisplatin/vinblastine/bleomycin/ifosfamide/etoposide. Additionally, 11 patients with germ cell tumors (age 22 to 38 years, stage I) were investigated within the first year after orchiectomy and retroperitoneal lymphadenectomy but without chemotherapy. RESULTS: In the transversal trial, 24 of 73 patients investigated during the first year after chemotherapy showed elevated luteinizing hormone concentrations, 5 had subnormal serum testosterone and 65 had elevated serum follicle-stimulating hormone, reflecting spermatogenesis deficits. In 28 patients studied longer than 8 years after chemotherapy (median followup 8.5 years, range 8.0 to 12.6), luteinizing hormone increased after chemotherapy and 60 months after treatment, and follicle-stimulating hormone was elevated in 1 patient, follicle-stimulating hormone was increased in 18 and testosterone was subnormal in 1. Patients without chemotherapy treatment showed gonadotropin and testosterone within normal range and 3 patients had elevated serum follicle-stimulating hormone. In the longitudinal study, mean serum luteinizing hormone plus or minus standard deviation (3.45 +/- 0.05 IU/l.), follicle-stimulating hormone (7.79 +/- 0.13 IU/l.) and testosterone (18.6 +/- 0.17 nmol./l.) were within the normal range before chemotherapy; serum follicle-stimulating hormone was still significantly elevated (16.9 +/- 0.71 IU/l., 19 cases, p < 0.001). Mean luteinizing hormone and testosterone levels were within the normal range, but 60 months after therapy the testosterone-to-luteinizing hormone ratio was still lower than before treatment (p < 0.05). CONCLUSIONS: In patients with germ cell tumors, a compensated insufficiency of the function of the Leydig cells was still observed up to 60 months after chemotherapy. Of these patients 68% showed elevated follicle-stimulating hormone levels, which reflected a functional insufficiency of the Sertoli cells with impaired spermatogenesis. This study shows that impairment of germinative functions is more severe and protracted than the impairment of the endocrine functions.

Adolescent↗
PubMed1995

Clinical significance of serum S100 in metastatic malignant melanoma.

The clinical significance of serum S100 was assessed in comparison to neuron-specific enolase (NSE) in 126 patients with malignant melanoma: 80 patients with clinical stage I/II, 23 patients with stage III and 23 patients with stage IV according to the criteria of the American Joint Committee on Cancer (AJCC). Using cut-off values of 0.15 micrograms/l for S100 and 12.5 micrograms/l for NSE, the sensitivity was found to be 1.3% (1/80) for S100 and 8.75% (7/80) for NSE in patients with stage I/II, 8.7% (2/23) for S100 and 13% (8/23) for NSE in patients with stage III, and 73.9% (17/23) for S100 and 34.8% (8/23) for NSE in patients with stage IV disease (P < 0.05). In 6 patients with stage III/IV tumours, serial measurement of serum S100 and NSE was performed. A rise of serum S100 indicated progression of the disease; a decline indicated response to treatment. Our preliminary results support the value of serum S100 as an adjunct to the clinical staging and monitoring of metastatic malignant melanoma.

Adult↗
PubMed1995

Clinical significance of serum S100 in metastatic malignant melanoma.

The clinical significance of serum S100 was assessed in comparison to neuron-specific enolase (NSE) in 126 patients with malignant melanoma: 80 patients with clinical stage I/II, 23 patients with stage III and 23 patients with stage IV according to the criteria of the American Joint Committee on Cancer (AJCC). Using cut-off values of 0.15 microgram/l for S100 and 12.5 micrograms/l for NSE, the sensitivity was found to be 1.3% (1/80) for S100 and 8.75% (7/80) for NSE in patients with stage I/II, 8.7% (2/23) for S100 and 13% (8/23) for NSE in patients with stage III, and 73.9% (17/23) for S100 and 34.8% (8/23) for NSE in patients with stage IV disease (P < 0.05). In 6 patients with stage III/IV tumours, serial measurement of serum S100 and NSE was performed. A rise of serum S100 indicated progression of the disease; a decline indicated response to treatment. Our preliminary results support the value of serum S100 as an adjunct to the clinical staging and monitoring of metastatic malignant melanoma.

Aged↗
PubMed1995

Effects of the gonadotropin-releasing-hormone agonist, D-Trp-6-GnRH, on prolactin secretion in healthy young men.

The objective of this study was to examine the changes in basal plasma gonadotropin, alpha-subunit, sex steroids, and prolactin levels and the prolactin and luteinizing hormone (LH) secretion pattern before, during and 161 days after treatment with a depot preparation of D-Trp-6-GnRH in young men. Gonadotropins, alpha-subunit, sex steroids, and prolactin were measured in pooled plasma samples. Additionally, before treatment, several times during its course and on day 161 after treatment, blood samples were drawn for 8 h every 15 min for prolactin and LH measurements. After initial stimulation of the pituitary, administration of a depot preparation of D-Trp-6-GnRH resulted in a constant decrease in gonadotropin and sex steroid concentrations with LH and testosterone concentrations remaining within the limits of prepubertal levels from days 16 to 48. Alpha-Subunit concentrations (0.4 +/- 0.09 IU/l; mean +/- SE) increased after application of D-Trp-6-GnRH, and remained elevated until day 48. Basal prolactin levels (3.5 +/- 0.25 microgram/l) did not change significantly during treatment but afterwards increased consistently with maximal levels at day 141 (15.3 +/- 3.8 microgram/l); they had decreased at day 161 to 10.3 +/- 1.8 microgram/l which is significantly higher than before treatment (p < 0.05). On day 161, prolactin pulse amplitude was significantly higher than before and during treatment (p<0.05), while no significant changes in pulse frequency occurred. No significant temporal coupling between LH and prolactin release could be detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Secretion pattern of immunoreactive inhibin in men.

Chronological changes in serum concentrations of inhibin, a gonadal glycoprotein hormone, were studied in healthy male volunteers (age 24-27 years). Secretion profiles of immunoreactive inhibin (ir-inhibin) were compared with those of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone. Blood samples were collected every 15 min for 24 h. Serum inhibin concentrations were measured by a two-site immunoenzymatic assay with antibodies raised against distinct epitopes of the recombinant 1-32 amino acids of the alpha-subunit of human inhibin. The normal range for men was 0.79-3.1 U/l x 10(-3), the sensitivity of the assay was 0.1 U/l x 10(-3) (cv: within-assay, 6.8%; between-assay, 8.2%). Luteinizing hormone and FSH were measured by immunoradiometric assay and testosterone by radioimmunoassay. Secretion profiles of inhibin and testosterone were tested for diurnal variations by cosinor rhythmometry. Highest ir-inhibin concentrations were observed in the morning at 08.00 h, with peak values of 2.45-3.20 U/l x 10(-3). During the evening and the night, ir-inhibin levels were relatively low; lowest concentrations were observed between 01.00 h and 02.00 h at night: 1.20-1.86 U/l x 10(-3). Highest testosterone levels were observed in the morning (20.5-36.6 pmol/l), lowest concentrations were detected at night (7.35-12.6 pmol/l). Cosinor rhythmometry supported the suggestion that there is a clear circadian secretion of ir-inhibin and testosterone, respectively. The secretion pattern of ir-inhibin was analyzed by the Cluster pulse analysis computed algorithm, which identified four to seven inhibin pulses per day, depending on the person under observation.2+ volunteers follow a clear diurnal rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Immunoreactive plasma inhibin levels in men after polyvalent chemotherapy of germinal cell cancer.

In vitro studies have shown that the Sertoli cell is the primary source of inhibin in the male. We measured immunoreactive inhibin with a new two-site immunoenzymatic assay in the plasma of 92 men: 40 normal men, 7 patients with germinal cell cancer after unilateral orchidectomy and 45 patients with the same disease following unilateral orchidectomy and subsequent chemotherapy based on cisplatin. Normal men had inhibin levels of 1.77 +/- 0.09 U/l x 10(-3) (mean +/- SEM). Seven patients after unilateral orchidectomy had inhibin concentrations within the lower normal range (1.23 +/- 0.22 U/l x 10(-3)). Forty-five patients were investigated in a cross-sectional study up to 102 months after completion of chemotherapy. Inhibin levels were within the normal range in 25 patients (1.76 +/- 0.14 U/l x 10(-3)); 18 patients had significantly lower inhibin levels (0.48 +/- 0.05 U/l x 10(-3), p less than 0.005) when compared to patients after unilateral orchidectomy. Two patients had elevated inhibin levels (4.4 and 5.6 U/l x 10(-3)). The proportion of patients with normal and subnormal inhibin was not dependent on the time that elapsed after completion of chemotherapy or on the chemotherapy combination. There was no correlation between immunoreactive plasma inhibin and LH, FSH, testosterone or sperm count. The decrease in inhibin concentrations after chemotherapy may indicate long-term damage to Sertoli cells in some of the patients.

Adult↗
PubMedDate not supplied

Expression of CYP19 (aromatase) mRNA in different areas of the human brain.

The conversion of androgens to estrogens by CYP19 (cytochrome P450AROM, aromatase) is an important step in the mechanism of androgen action in the brain. CYP19 expression has been demonstrated in the brain of various animal species and in the human temporal lobe. Studies on postnatal CYP19 expression in various other areas of the human brain are rare and carried out in a limited number of post mortem obtained tissue. Therefore, we investigated CYP19 mRNA expression in fresh human frontal and hippocampal tissues and compared them to the expression in temporal neocortex tissues. We studied biopsy materials removed at neurosurgery from 45 women and 54 men with epilepsy. Quantification of CYP19 mRNA was achieved by nested competitive reverse transcription-PCR. CYP19 mRNA concentrations were significantly higher in temporal (2.29+/-0.40 arbitrary units, AU, mean +/- SEM; n = 57) than in frontal neocortex specimens (0.92+/-0.17 AU; n = 18; P<0.04). In hippocampal tissue specimens CYP19 expression (1.41+/-0.18 AU; n = 24) was lower than in temporal neocortex specimens, but the difference did not reach statistical significance. Sex differences were not observed in any of the brain regions under investigation. In conclusion, CYP19 mRNA is expressed in the human temporal and frontal neocortex as well as in the hippocampus. Regardless of sex, CYP19 expression was significantly higher in the temporal than in the frontal neocortex.

Adult↗