Search PubMed⌕ Search

Biomedical subjects

E Leicht

Publications and source records attributed to E Leicht.

At least 19 recordsLinked to original sources

Oncogenic osteomalacia: imaging studies.

X-ray und NMR imaging studies of a 34-year-old patient with tumor-induced hypophosphatemic osteomalacia (OM) are presented. Besides typical features of OM, periosteal new bone formation was noticed initially. After 17 months of conservative treatment with supplements of inorganic phosphorus and 1,25-dihydroxyvitamin D, bone density had increased but Looser's zones were still present, while periosteal new bone formation was strikingly less evident. At this time a tumor in the first left metatarsal space became palpable, was surgically excised and proved to be a low-grade synovial sarcoma with hypervascular and partially calcified structures. Six months later an X-ray survey showed no more signs of metabolic osteopathy. Preoperatively, the pronounced vascularity of the tumor could be demonstrated by angiography and NMR scanning.

Adult↗

[Sphincter-preserving radiotherapy of anal carcinoma].

During the last decade radiotherapy, in combination with chemotherapy, has become the treatment of choice in cure of anal carcinoma with preservation of anal function, and has replaced abdominoperineal resection (APR). From 1979-1990 54 patients with anal carcinoma were treated by radiotherapy. 24 patients received radiotherapy after APR (12 adjuvant, 12 after recurrence). 11 received palliative radiotherapy without prior APR. 19 patients were treated curatively, 17 of whom received a combination of external irradiation followed by interstitial iridium implantation in a split course regimen. 11 of the 19 patients received short simultaneous chemotherapy (mitomycin C and 5-fluorouracil). All 19 patients had a complete remission. 18/19 patients had no local recurrence after mean 14 months' follow-up. 2 patients developed regional recurrence. 3 patients died of other causes. Colostomy was necessary in 5/19 patients with anal necrosis which was dose-related. The maximum tolerated dose was 71.4 Gy. Our results support the recommendation in the literature of primary, curative, radiotherapy and chemotherapy of anal carcinoma with preservation of the anal sphincter.

Adult↗

[Cardiac function and the skin microcirculation in acromegaly].

The microcirculation was measured by nail-fold capillary video microscopy in 21 patients (12 men, 9 women; mean age 54.7 [29-74] years) with acromegaly. Levels of growth hormone (12.0-71.7 microU/ml) and of somatomedin C (2.4-10.5 IU/ml) were elevated in 10 patients, despite preceding treatment. Eleven patients had an increase in myocardial thickness and nine had impairment of left ventricular function, although only slight in most. Left ventricular hypertrophy was demonstrable even in the absence of hypertension. No patient had evidence of coronary heart disease. Nail-fold capillary video microscopy (capillary density, torque index, reactive hyperaemia, epidermal blood flow) failed to distinguish between successfully treated patients and those with persistently elevated growth hormone concentrations or disease duration of over 5 years. There was no evidence of inadequate capillary blood flow as a cause of abnormal function in hypertrophied organs.

Acromegaly↗

Hypomagnesaemia-induced hypocalcaemia: concentrations of parathyroid hormone, prolactin and 1,25-dihydroxyvitamin D during magnesium replenishment.

Three patients with hypomagnesaemia-induced hypocalcaemia were investigated during the phase of magnesium replenishment. Before treatment, serum levels of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were at the lower limit of normal. In spite of a rapid rise of parathyroid hormone (PTH) after intravenous administration of magnesium, a reactive increase in 1,25-dihydroxyvitamin D in serum was absent or delayed. The increase of serum calcium into the normal range occurred before any consistent change in the concentrations of this vitamin D metabolite. The rise of serum prolactin in response to the increase in PTH was blunted or absent, and is a further example of a transient PTH resistance during the phase of magnesium replenishment.

Alcoholism↗

Mechanisms of hypocalcaemia in the clinical form of severe magnesium deficit in the human.

Severe magnesium depletion leading to hypocalcaemia has been described in a variety of clinical settings. Inadequately low concentrations of parathyroid hormone (PTH) are a constant feature of hypomagnesaemic hypocalcaemia (HMHC), while target organ resistance to PHT in kidneys and bone may be demonstrated in the majority of these patients. The failure of membrane-bound adenylate cyclase in the parathyroids, kidneys and bone, thought to be the most important molecular mechanism in HMHC, cannot explain the concomitant resistance to vitamin D and its metabolites. In recent years, information has accumulated on further magnesium-dependent intracellular events and alternative pathways of transcellular signalling. This may eventually allow the identification of one or more further biochemical mechanisms leading to hypocalcaemia in severe magnesium deficiency.

Adenylyl Cyclases↗

Development of a luminescence immunoassay for follitropin suitable for clinical routine.

We developed a luminescence immunoassay (LIA) for follitropin, based on the synthesis of a follitropin-N-(4-aminobutyl)-N-ethylisoluminol conjugate. The luminescence tracer was purified by gel chromatography. Antibody-bound and non-bound tracer fractions were separated by using a second antibody reagent bound to magnetic particles. The assay can be performed within 24 hours and is sufficiently sensitive for the measurement of all clinically relevant follitropin concentrations including the subnormal range.

Analysis of Variance↗

[Hypomagnesemia-induced hypocalcemia: functional hypoparathyroidism, parathyroid hormone- and vitamin D-resistant].

In four patients with severe hypomagnesemia, hypocalcemia, and functional hypoparathyroidism (three patients with shortened bowel, one with alcoholism), sequential measurements of parameters of calcium metabolism were performed before and during intravenous administration of magnesium. Parathyroid hormone was immeasurably or inadequately low in all patients before magnesium injection, but rapidly rose to elevated values thereafter. Even without calcium supplements, serum calcium rose to normal levels within 2-5 days, although 1,25(OH)2-Vitamin D levels did not rise significantly. In the patient with alcoholism, hypophosphatemia developed during the first days after admission; the rise of serum calcium preceded the elevation of cyclic adenosine monophosphate in urine. A transient rise of urinary calcium was observed in two patients after initiation of magnesium therapy, with a subsequent fall to subnormal levels in spite of normal serum calcium concentrations. The findings were considered to be due to partial parathyroid hormone resistance during the phase of magnesium replenishment.

Adult↗

[Familial nonneoplastic inappropriate thyrotropin secretion].

A follicular thyroid carcinoma was suspected in a 62-year-old woman after the fifth goitre excision for non-neoplastic inappropriate thyrotropin secretion. Small-follicular adenoma could not be excluded histologically. After an attempt at thyrotropin suppression with L-thyroxine, triiodothyronine, D-thyroxine with L-thyroxine, and bromocriptine had failed, lasting if partial decrease in the maximally elevated TSH levels was achieved with triiodothyroacetic acid (TRIAC). One of the patient's three daughters also has non-neoplastic inappropriate thyrotropin secretion and has had two goitre excisions. It is most likely a familial form of inappropriate TSH secretion.

Carcinoma↗

Tumor-induced osteomalacia: pre- and postoperative biochemical findings.

A patient with late-onset hypophosphatemic osteomalacia was treated with oral supplements of phosphate (1.5 g/day) and calcitriol (1.5-3.0 micrograms/day) for 17 months, before a slowly growing tumor in the first metatarsal space became evident. Before treatment concentrations of inorganic phosphate (Pi) and calcitriol in serum and tubular reabsorption of phosphate (TRP) were very low, calcium and parathyroid hormone (PTH) in serum were normal, urinary cyclic adenosine monophosphate (cAMP) was strongly elevated. During the first weeks of conservative treatment urinary cAMP returned to normal; concomitantly there was a transient slight fall in PTH. Serum calcium was in the low normal range and did not significantly change during conservative therapy. During the further course PTH rose to pretreatment values, but urinary cAMP remained normal. When the dose of calcitriol was elevated to 3 x 1.0 micrograms/day, leading to slightly elevated serum concentrations of this substance, Pi in serum rose to the low normal range, but TRP remained low and bone pain, although improved, did not subside. The tumor was locally excised. Postoperatively calcitriol concentration became elevated within 48 hours and remained so for several weeks. The rise in calcitriol concentration preceded the elevation of Pi in serum, not, however, the increase of TRP. The elevation of urinary cyclic AMP before therapy may have been due to a direct action of the substance secreted by the tumor.

Adult↗

Functional difference between "classical" neurosecretory material and vasopressin-like substances of the outer layer of the median eminence.

In female Wistar rats the influence of adrenalectomy and NaCl administration on the amount of "classical" neurosecretory material (cNSM) in the supraoptico-hypophysial system and on vasopressin-like substance-containing granules (vlG) in the outer layer of the median eminence has been studied. In conjunction with appropriate sodium replacement, adrenalectomy induces an increase in the amount of vlG but does not alter the amount of cNSM. Administration of hypertonic saline diminishes cNSM but has not or only little influence on the amount of vlG. From the findings it is concluded that cNSM and vlG, in spite of their identical histochemical and immunohistochemical properties, have different functions. The functional significance of the vlG is discussed.

Adrenalectomy↗

Tumoral calcinosis. Observations during six years.

Findings of a 56 year old woman suffering from tumoral calcinosis, who was treated for 6 years, are presented. Under conditions known to lead to negative calcium-phosphorus balance, a reduction in tumor size was seen. Transient hypercalcemia was attributed to immobilization. The process of tumor reduction was not definitely accelerated by treatment with ethane-hydroxy-diphosphonate (EHDP; 500 mg/day for 20 months). Nephrotic syndrome as a consequence of amyloidosis developed. Amyloidosis seems to have resulted from the aseptic histiocytic inflammatory process in the tumors. The possible importance of high cholesterol in very low density lipoproteins in the serum of the patient is discussed.

Amyloidosis↗

Tumoral calcinosis: accumulation of bone-seeking tracers in the calcium deposits.

Rapid and preferential uptake of 47 calcium 87m Strontium by the multinodular calcareous masses was seen in a patient with tumoral calcinosis. Using 87m Strontium, scintigraphic imaging of the tumors was achieved, while the skeleton was barely visible. More intense accumulation of 87m Sr. in one tumor suggested a higher rate of calcium depostion. This was in agreement with the observation that this tumor showed less tendency to decrease in size during calcium and phosphorus deprivation therapy. Quantitative measurements of the uptake of bone seeking tracers by the tumors may be of value in estimating calcium turnover in the calcified masses.

Calcinosis↗

Phosphonopeptides as antibacterial agents: metabolism and pharmacokinetics of alafosfalin in animals and humans.

The metabolism and pharmacokinetics of a synthetic antibacterial phosphonodipeptide, alafosfalin, have been studied in rats, baboons, and human volunteers. The compound was rapidly absorbed from the injection site after subcutaneous and intramuscular administration and gave peak plasma concentrations at 15 to 20 min after dosing. Distribution studies showed that high drug concentrations were produced in inflammatory exudates and most tissues except brain. Alafosfalin was rapidly cleared from the general circulation, mainly by the kidney. Plasma half-lives were 20 min in rats and approximately 1 h in baboons and humans. Alafosfalin was well absorbed after oral administration, but was extensively hydrolyzed to alanine and L-1-aminoethylphosphonic acid before it reached the general circulation. This first-pass metabolism was less marked in humans than in animals. Administration of 200-mg intramuscular and 500-mg oral doses produced concentrations of intact phosphonodipeptide in human plasma and urine which were in excess of the in vitro minimal inhibitory concentrations for many pathogenic organisms. The rate of absorption and elimination of alafosfalin in humans were also very similar to published data on beta-lactam antibiotics. This suggests that the pharmacokinetics can be matched to provide synergistic combinations for clinical use.

Alanine↗

[Hyperthyroidism with hypercalcaemia (author's transl)].

Anorexia, constipation, vomiting and somnolence in a 39-year-old woman were at first misinterpreted as being of psychological and autonomic nervous system origin. Further clinical and biochemical tests revealed hyperthyroidism associated with hypercalcaemia and hypercalciuria. Thyrostatic treatment for 12 days caused regression of the hypercalcaemia and, after subtotal resection, serum calcium levels and urinary calcium excretion returned to normal for good. The hypercalcaemia syndrome must therefore be assumed to have been the direct result of the hyperthyroidism.

Adult↗