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B Saller

Publications and source records attributed to B Saller.

At least 37 records · Page 2Linked to original sources
PubMed2001

Posterior retroperitoneoscopic adrenalectomy: lessons learned within five years.

Posterior retroperitoneoscopic adrenalectomy is one of the new endoscopic methods in endocrine surgery. In a prospective clinical study 142 posterior retroperitoneoscopic adrenalectomies (72 right, 70 left) were performed in 130 patients (52 males, 78 females, age 49.1 +/- 14.9 years). Indications were primary adrenal tumors (unilateral, n = 118; bilateral, n = 2), adrenal metastases (n = 2), and bilateral ACTH-dependent hyperplasias (n = 10). Tumor size ranged from 0.5 to 7.0 cm (mean 2.7 +/- 1.4 cm). Partial adrenalectomies were performed in 39 patients. Conversion to open posterior adrenalectomy was necessary in five patients and seven procedures (5%). Intraoperative and postoperative complications were minor and occurred in 5% and 13%, respectively. Mortality was zero. Operating time was 101 +/- 39 minutes (range 35-285 minutes) and depended on tumor type (pheochromocytoma versus others; p < 0.01), tumor size (< 3 vs. > or = 3 cm; p < 0.05), gender (p < 0.05), and extent of resection (partial versus complete, p < 0.05. Twenty-three adrenalectomies (17%) were performed within 1 hour or less. Blood loss was 54 +/- 72 ml. Consumption of analgesics was low (mean 6 mg piritramide postoperatively). Median duration of hospitalization was 3 days. Posterior retroperitoneoscopic adrenalectomy is a safe method that has become a standard procedure in endocrine surgery.

Adenoma↗
PubMed2001

Occurrence of ventricular late potentials in patients with active acromegaly.

OBJECTIVE: Patients with acromegaly have an increased risk of ventricular dysrhythmias and sudden death. Late potentials in a signal-averaged electrocardiogram (SAECG), a predictor of ventricular dysrhythmias, are frequently seen in patients after previous myocardial infarction, but little is known about the prevalence of late potentials in acromegaly. The aim of our study was to investigate the prevalence of late potentials in patients with acromegaly and their relation to the activity of the disease and to myocardial hypertrophy. PATIENTS: The study included 48 patients with acromegaly [27 males, 21 females, mean age 52.3 +/- 14.2 years, 16 active disease, 32 cured or 'well controlled', under treatment with sandostatin analogues (12/32)] and 38 healthy volunteers as a control group. RESULTS: Late potentials were detected in 9/16 (56%) patients with active acromegaly vs. 2/32 (6%) with cured/well controlled acromegaly (P = 0.001), defined as normal age-related IGF-1 levels and GH levels suppressible below 1 microg/l after an oral glucose load (75 g). Late potentials were not related to muscle mass index (127 +/- 35 active vs. 123 +/- 34 g/m2 cured/well controlled). The association of disease activity with the detection of late potentials was independent of age, gender, duration of the disease and body mass index. In comparison to the control group, the prevalence of late potentials was significantly higher in patients with acromegaly (23%) than in the control group (0%; P < 0.001). CONCLUSIONS: Late potentials in the SAECG are frequently seen in active acromegaly and may represent an early and sensitive parameter to detect myocardial injury in acromegaly.

Acromegaly↗
PubMed2001

Diurnal variation of abdominal motor responses to colorectal distension and plasma cortisol levels in rats.

Most patients with functional bowel disorders complain of daytime symptoms while they remain asymptomatic at night. As symptoms are associated with heightened visceral sensitivity, we hypothesized that circadian fluctuations of the visceral sensory function occur. At four different timepoints (06.00, 12.00, 18.00 and 24.00 h), colorectal distensions (CRD) were performed in fasting conscious male Lewis rats using a balloon catheter and a barostat device. The abdominal wall contractions (behavioural pain response) were assessed during colorectal distension by abdominal wall electromyography (EMG). Plasma levels for endogenous cortisol were determined simultaneously at these timepoints. EMG responses to CRD were significantly (P < 0.05) higher at midnight and in the early morning. Plasma cortisol levels peaked in the evening. In night-active Lewis rats, the behavioural pain response to noxious visceral stimulation is augmented at night and fluctuations of visceral sensitivity are accompanied by circadian changes of plasma concentrations of endogenous cortisol. We conclude that there are marked circadian fluctuations in visceral sensory functions. Thresholds are low during time periods of normal behavioural activity. These findings suggest that fluctuation of the sensory functions may be linked to the circadian variability of symptoms in patients with functional GI disorders.

Abdomen↗
PubMed2001

Transient stimulatory effects on pituitary-thyroid axis in patients treated with interleukin-2.

It has been shown that various cytokine therapies may influence thyroid hormone parameters that may lead to serious side effects including nonthyroidal illness. Interleukin-2 is effective in increasing CD4-T cell numbers in human immunodeficiency virus (HIV)-infected patients and it is used in the treatment of various malignant tumours. However, the association of interleukin-2 (IL-2) therapy and thyroid function is not clearly established as serial systematic measurements of thyroid parameters have not been performed with interleukin-2 as the sole therapeutic agent. Therefore, it was the aim of this study to examine prospectively the impact of a 5-day interleukin-2 therapy on thyroid parameters in asymptomatic HIV-infected patients. Twenty male euthyroid patients (mean age, 42.6 +/- 3.2 years; body weight, 73.4 +/- 3.0 kg) received 9,000,000 IU/d interleukin-2. Thyroid function was evaluated by measurements of serum thyrotropin (TSH), triiodothyronine (T3), thyroxine (T4), free thyroxine (FT4), reverse T3 (rT3), thyroglobulin (Tg), thyroxine-binding globulin (TBG), and anti-thyroid-peroxidase (TPO)-antibodies from day 1-4 and on days 7, 14, 20, 40, 60, 80, and 100. All results are given as mean +/- SD. On day 4, we observed a significant increase that was still within normal range of T4 and T3 (p < 0.05). TSH increased from 1.33 +/- 0.57 to 4.53 +/- 1.39 mU/l (p = 0.0001) and FT4 from 18.1 +/- 4.2 to 48.9 +/- 10.9 pmol/L (p = 0.0001) on day 4 with a gradual decrease thereafter. Normalization to baseline levels for TSH (1.45 +/- 0.75 mU/L) and FT4 (18.1 +/- 3.0 pmol/L) was achieved only on day 14. The increase of FT4 was more pronounced (well in the hyperthyroid range) than the increase in total T4 in the presence of normal TBG and albumin concentrations whereas TBG was not affected. We did not observe changes in anti-TPO-antibody levels up to day 100. Our data clearly demonstrate that the administration of interleukin-2 has a stimulatory effect on the pituitary-thyroid axis. The increase of TSH suggests a central stimulation directed by the action of IL-2 as the major mechanism.

Adult↗
PubMed2001

Induction of a cellular and humoral immune response against preprocalcitonin by genetic i: a potential new treatment for medullary thyroid carcinoma.

Currently, no effective therapy exists for patients suffering from progressive medullary thyroid carcinoma (MTC), a calcitonin (CT)-secreting C cell tumor. As CT, which arises from the precursor protein preprocalcitonin (PPCT), is expressed by almost all MTC cases, these molecules may represent target antigens for immunotherapy against MTC. In our study we investigated whether DNA immunization is able to induce cellular and humoral immune responses against human PPCT (hPPCT) in mice. Antigen-encoding expression plasmids were delivered intradermally by gene gun. One group of mice received DNA encoding hPPCT only. Two groups were coinjected with mouse cytokine genes. We observed in lymphocyte proliferative assays substantial proliferation against hPPCT in mice coinjected with the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene, in contrast to mice vaccinated with hPPCT expression plasmid only. In addition, codelivery of the GM-CSF gene augmented the frequency of anti-hPPCT antibody seroconversions in sera of immunized animals, as shown by enzyme-linked immunosorbent assay. These results illustrate that cellular and humoral immune responses against hPPCT can be generated by DNA immunization and increased by coinjection of the GM-CSF gene. Our findings may have implications for the use of DNA immunization as a potential novel immunotherapeutic treatment for patients suffering from progressive MTC.

Animals↗
PubMed2000

[Endoscopic excision of extra-adrenal pheochromocytomas (paragangliomas)].

We describe the successful endoscopic removal of six extra-adrenal pheochromocytomas in three patients. One neoplasia was located retrocavally, two between the aorta and vena cava, two by the para-aortal, and one by the parailiacal. The tumors were removed by the posterior retroperitoneoscopic or by the anterior laparoscopic approach, respectively. The intraoperative and postoperative courses were uneventful.

Adrenal Gland Neoplasms↗
PubMed2000

The value of fluorine-18 fluorodeoxyglucose PET in patients with medullary thyroid cancer.

The early detection of metastases from medullary thyroid cancer (MTC) is important because the only curative therapy consists in surgical removal of all tumour tissue. There is no single sensitive diagnostic imaging modality for the localization of all metastases in patients with MTC. Therefore, in many cases several imaging modalities (e.g. ultrasonography, magnetic resonance imaging, computerized tomography and scintigraphy using pentavalent technetium-99m dimercaptosuccinic acid, thallium-201 chloride, indium-111 pentetreotide, anti-CEA antibodies or metaiodobenzylguanidine) must be performed consecutively in patients with elevated calcitonin levels until the tumour is localized. In this prospective study, we investigated the value of fluorine-18 fluorodeoxyglucose positron emission tomography ([18F]FDG PET) in the follow-up of patients with MTC. [18F]FDG PET examinations of the neck and the chest were performed in 20 patients with elevated calcitonin levels or sonographic abnormalities in the neck. Positive [18F]FDG findings were validated by histology, computerized tomography or selective venous catheterization. [18F]FDG PET detected tumour in 13/17 patients (nine cases were validated by histology, four by computerized tomography). Five patients showed completely negative PET scans (of these cases, one was true-negative and four false-negative). One patient with [18F]FDG accumulation in pulmonary lesions from silicosis and one patient with a neck lesion that was not subjected to histological validation had to be excluded. Considering all validated localizations, [18F]FDG PET detected 12/14 tumour manifestations in the neck, 6/7 mediastinal metastases, 2/2 pulmonary metastases and 2/2 bone metastases. In two patients with elevated calcitonin levels, no diagnostic modality was able to localize a tumour. The sensitivity of [18F]FDG PET in the follow-up of MTC was 76% (95% confidence interval 53%-94%); this is encouraging. [18F]FDG PET promises to be a valuable diagnostic method, especially for the detection of lymph node metastases, surgical resection of which can result in complete remission.

Adult↗
PubMed2000

Neuroendocrine response to film-induced sexual arousal in men and women.

The psychoneuroendocrine responses to sexual arousal have not been clearly established in humans. However, we have demonstrated previously that masturbation-induced orgasm stimulates cardiovascular activity and induces increases in catecholamines and prolactin in blood of both males and females. We presently investigated the role of orgasm in producing these effects. Therefore, in this study parallel analysis of prolactin, adrenaline, noradrenaline, and cortisol concentrations, together with cardiovascular variables of systolic/diastolic blood pressure and heart rate were undertaken during film-induced sexual arousal in nine healthy adult men and nine healthy adult women. Blood was drawn continuously via an indwelling cannula and connected tubing system passed through a mini-pump. In parallel, the cardiovascular parameters were recorded continuously via a computerised finger-cuff sensor. Subjective sexual arousal increased significantly in both men and women during the erotic film, with sexual arousal eliciting an increase in blood pressure in both males and females, and plasma noradrenaline in females only. In contrast, adrenaline, cortisol and prolactin levels were unaffected by sexual arousal. These data further consolidate the role of sympathetic activation in sexual arousal processes. Furthermore, they demonstrate that increases in plasma prolactin during sexual stimulation are orgasm-dependent, suggesting that prolactin may regulate a negative-feedback sexual-satiation mechanism.

Adult↗
PubMed2000

Primary malignant fibrous histiocytoma of the lung: IGF-II producing tumor induces fasting hypoglycemia.

Augmented glucose utilisation or secretion of insulin-like-growth-factor II (IGF-II) are discussed as important pathogenetic factors in tumor-associated hypoglycemia (Doege-Potter Syndrome) with suppressed insulin and C-peptide levels. Primary malignant fibrous histiocytoma of the lung is an uncommon neoplasia and its association with hypoglycemia is rare and the causal relationship remains unclear. - We report a 57-year-old male with spontaneous hypoglycemia (1.67 mmol/l) due to a primary malignant fibrous histiocytoma of the lung, secreting IGF-II. Insulin (0.10 nmol/l; normal range 0.33-1.2) and C-peptide (3.0 mIU/l; 5-25) levels were suppressed in combination with low levels of growth hormone (<0.5 ng/ml; <7 ng/ml) and IGF-I (<66.0 ng/ml; 70-246). The elevated IGF-II level (787 ng/ml; 300-500) and decreased IGF-binding protein 3 (1.6 mg/l; 2-5) indicated a high free IGF-II activity. After surgery (resection of the right upper lobe), glucose (4.4 mmol/l), insulin (9.0 mIU/L) and C-peptide (0.84 nmol/l) levels returned to normal. Serum IGF-I (289 ng/ml) and the IGF-I/IGF-II ratio (<0.08 preoperative vs. 0.41 postoperative; >0.20) increased to the normal reference range. - In conclusion, malignant fibrous histiocytoma (MFH) is rarely described presenting as tumor-induced hypoglycemia. Doege-Potter Syndrome in MFH seems to be related to tumor-associated IGF-II production.

Adult↗
PubMed2000

Evaluation of chemiluminescence immunoassays for detecting thyroglobulin (Tg) and thyroid peroxidase (TPO) autoantibodies using the IMMULITE 2000 system.

The chemiluminescence assays for detection of autoantibodies to thyroid peroxidase (TPO) and thyroglobulin (Tg) implemented on the IMMULITE 2000 system (Diagnostic Products Corporation) were evaluated. These were immunometric assays with antigen-coated beads and monoclonal murine anti-IgG antibodies conjugated with alkaline phosphatase. Precision was satisfactory with an intraassay precision of 5.3-5.5% for anti-Tg and 4.8-5.3% for anti-TPO and an interassay precision of 5.7-7.3% for anti-TPO and 5.2-7.5% for anti-Tg. The lower detection limit was determined as 5 IU/ml for anti-TPO and 2.2 IU/ml for anti-Tg. The average dilution linearities of 102% for anti-TPO and 100% for anti-Tg and the average recovery of 80-127% for anti-TPO and 93-112% for anti-Tg were acceptable. The findings of the tests were compared with the systems from Pharmacia & Upjohn, ORGenTec, Roche Diagnostics, Byk Sangtec Diagnostica and BRAHMS Diagnostica. Taking the respective cutoff value into account, concordance was 87-96% for anti-Tg and 87-97% for anti-TPO. Summarizing all results from the different methods revealed a clinical agreement of 95% for anti-TPO and 93% for anti-Tg. A good agreement was found with the IMMULITE anti-TPO and anti-Tg assays, which are closely related as regards method and biochemistry. Regression analysis gave the following results: anti-TPO IMMULITE 2000 vs anti-TPO IMMULITE: anti-TPO IMMULITE 2000 = 0.99 x IMMULITE anti-TPO - 1.43 IU/ml (r = 0.99, n = 144). anti-Tg IMMULITE 2000 vs anti-Tg IMMULITE: anti-Tg IMMULITE 2000 = 0.98 x IMMULITE anti-Tg + 1.63 IU/ml (r = 0.99, n = 86). Further age-dependent normal ranges were evaluated. A higher prevalence of elevated autoantibody titers was found for patients older than 50 years. The rate of elevated antibody titer can be reduced by using an age-dependent reference range: < or = 50 years anti-TPO < 35 IU/ml, anti-Tg < 40 IU/ml and > 50 years anti-TPO < 100 IU/ml, anti-Tg < 80 IU/ml. Further samples from clinically diagnosed Hashimoto's thyroiditis and Graves' disease were investigated. The levels of positive anti-Tg values and anti-TPO values accorded with those stated in the literature and were comparable to those measured with a reference assay. In the tested INSTAND e. V. interlaboratory samples there was high-level accordance with the expected clinical results.

Antibodies, Monoclonal↗
PubMed1998

Subtotal adrenalectomy by the posterior retroperitoneoscopic approach.

The retroperitoneoscopic approach offers an established operative procedure for primary adrenal gland tumors. It allows a detailed view of the adrenal gland and its surrounding region. Therefore clear differentiation between normal and neoplastic adrenal tissue is sometimes possible, permitting a planned, unilateral, subtotal resection of the gland. Between July 1994 and August 1997 primary benign adrenal gland tumors (11 Conn adenomas, 4 phenochromocytomas, 4 Cushing adenomas, 3 hormonally inactive tumors; 2.4 +/- 1.2 cm in size; 8 on the right, 14 on the left) were removed from 22 patients by the posterior retroperitoneoscopic approach maintaining tumor-free portions of the ipsilateral adrenal gland. Two patients suffered from bilateral pheochromocytomas associated with multiple endocrine neoplasia (MEN-IIa) syndrome and had previously undergone complete adrenalectomy of the contralateral gland. Following subtotal resection the operating time and blood loss did not differ significantly (p > 0.05) from that seen with complete extirpation (46 patients operated during the same period). All patients with Conn adenomas and pheochromocytomas were biochemically and clinically cured (follow-up 11 months; range 1-31 months). The four patients with Cushing adenoma currently require decreasing cortisol substitution. In the two MEN-II patients adrenal gland cortical function could be maintained; one patient is on low-dose steroid supplementation and the other on none. No local recurrence of tumors has been observed. In selected cases the retroperitoneoscopically performed subtotal adrenal gland resection is a safe procedure that can potentially maintain the function of the adrenal gland cortex.

Adolescent↗
PubMed1998

T3-release from autonomously functioning thyroid nodules in vitro.

Toxic thyroid nodules have been shown to be of clonal origin. In a portion of them, point mutations affecting either the gene of the TSH receptor (TSHr) or the alpha-subunit of stimulating G-protein, consecutively leading to enhanced cAMP levels, which may enhance growth or functional activity of the thyrocyte or both, were recently found. To complement these studies, we evaluated hormone response (i.e. T3 release) in vitro from tissues derived from toxic thyroid nodules as compared directly to the surrounding paranodular tissues as well as tissues derived from euthyroid goiter and from patients with Graves' disease. Experiments were conducted in the presence and absence of bTSH or Graves' immunoglobulines. Tissues obtained during surgery were incubated over 5 h, followed by equilibrium dialysis for 24 h, and determination of free T3 in an aliquot by RIA. Basal T3 release in nodular tissues (n = 10) was significantly higher (median: 7.3 ng/l) compared to paranodular tissues (3.2 ng/l; P < 0.01), tissues derived from euthyroid goiter (1.3 ng/l; n = 12; P < 0.001) and thyroid tissues derived from patients with Graves' disease (2.5 ng/l; n = 6; P < 0.001). Upon stimulation with bTSH (1 IU/l), median T3 concentrations markedly increased to 11.5 ng/l (P < 0.05), 7.3 ng/l (P < 0.05), 4.2 ng/l (P < 0.01) and 3.2 ng/l (P = N.S.), respectively. Stimulation over basal values was 1.6-fold in nodular tissues, 2.3-fold in paranodular tissues, 3.2-fold in euthyroid goiter and 1.3-fold in Graves' disease. In toxic thyroid nodules basal hormone-releasing activities were stimulated by fifteen out of twenty (75%) Graves' sera tested. For comparison, stimulation in other tissues occurred in 45% (paranodular), 80% (euthyroid goiter) and 35% (Graves' disease), respectively. In conclusion, tissue derived from toxic thyroid nodules exhibits enhanced basal hormone release as compared to both, the surrounding paranodular tissues and tissues from euthyroid goiter in vitro, which may reflect constitutional activation of TSHr, alpha-subunit of stimulating G-protein or other so far unknown intermediate by point mutations affecting the respective genes. Hyperactivities in toxic thyroid nodules may be even further enhanced by external stimulators such as TSH or TSH receptor antibodies. The first stimulator may have clinical relevance in patients with toxic thyroid nodules and not yet suppressed TSH; the latter could play a role in the rare Marine Lenhart syndrome.

Adult↗
PubMed1998

Kinetics of acute and chronic iodine excess.

Iodine plays an important role in thyroid physiology resulting from its importance as a requisite substrate for the synthesis of thyroid hormones and from its action as a regulator of thyroid function. Following intestinal absorption, inorganic iodide is largely confined to the extracellular fluid. Serum concentrations of inorganic iodide well reflect the amount of iodine present in the extracellular compartment. Since serum inorganic iodide levels are important determinants of thyroid iodine uptake, serum iodide measurement offers a valuable tool for the investigation of many basic and clinical aspects of thyroid iodine metabolism. Here we summarize important aspects of iodine metabolism and focus selectively on technical aspects of serum inorganic iodide measurement and on the kinetics of inorganic iodide in various states of iodine excess. Presently, paired-ion, reversed-phase HPLC with electrochemical detection is obviously the best method for measurement of serum inorganic iodide being highly sensitive, easy to perform, and almost completely insensitive to interfering substances. Using this method, we could demonstrate an acute increase of serum inorganic iodide during the administration of large amounts of iodide as Lugol's solution given preoperatively in patients with Graves' hyperthyroidism. In patients under treatment with the iodine containing drug amiodarone (n=37), serum inorganic iodide levels were highly elevated (range 3.5-208.2 microg/dl, median 36.6 microg/dl). Serum concentrations of inorganic iodide were correlated neither to the daily amiodarone dose, nor to the serum levels of amiodarone.

Acute Disease↗