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Biomedical subjects

D Schmidt

Publications and source records attributed to D Schmidt.

At least 469 records · Page 26Linked to original sources
PubMed1986

Progabide for refractory partial epilepsy: a controlled add-on trial.

Progabide, an experimental GABA-ergic antiepileptic drug, was given in a placebo-controlled double-blind cross-over trial to 19 adult patients with chronic partial epilepsy refractory to previous high-dose antiepileptic drug therapy. A mean daily dose of 32 mg/kg (range, 16 to 63) of progabide did not significantly change the seizure frequency. In patients with a therapeutic response, progabide led to an increase in the plasma concentration of phenytoin and phenobarbital. Comedication with carbamazepine was associated with a poor response to progabide. Side effects were mild except for a several-fold increase of SGOT and SGPT, which required withdrawal of progabide in one patient. Progabide does not seem to be the drug urgently needed for failures of previous high-dose drug therapy.

Adolescent↗
PubMed1986

Photometric determination of phospholipase A.

A photometric method for the determination of phospholipase A is described, in which fatty acids are liberated from phosphatidylcholine and measured by a discontinuous enzymatic test. Optimal test conditions were evaluated using purified phospholipase A from human and porcine pancreas. The enzyme activities measured in normal human sera are in the range of 0 to 10 U/l. Pathological values reach more than 100 U/l. There is no correlation with the activities of lipase or amylase in cases of acute pancreatitis.

Amylases↗
PubMed1986

[Malignancy grading of glial tumors. II. Oligodendrogliomas].

Surgical biopsy material from 55 oligodendrogliomas was classified according to a four-level system of malignancy grading. Categorization was based on following criteria: numerical cell-density, cell and nuclear polymorphism, mitotic activity, proliferative activity of the vascular elements and degenerative phenomena, in particular necrosis. According to the intensity of these features, tumors were assigned to a malignancy level. The number of tumors alloted to each of the four ascending levels were 7, 15, 19, and 14, respectively with corresponding median survival times of 61.7, 27.7, 19.5, and 7.4 months. There was no statistically significant difference in the duration of survival between levels 2 and 3. The results of the investigation are consistent with reports from the literature which identify three prognostic grades for oligodendrogliomas, namely a group with low malignancy and a relatively good prognosis, an intermediate group and a group with a high level of malignancy and an extremely poor prognosis. It is suggested that the use of automated microscope image analysis or other quantitative methods contribute to more objective and reliable results.

Biopsy↗
PubMed1986

[Therapy of breast cancer].

Mammary carcinoma is the most common cancer of women. A brief statistical account is followed by reference to operative techniques for mammary carcinoma, in general, and to stage-related therapy, in particular. Mention is made of the unresolved problem of systemic disease or locally delimited lesion, with latest knowledge being reported. For standard surgery to cope with stages I and II (III) modified radical mastectomy has replaced classical radical mastectomy. Adequate therapy for mammary carcinoma should be aimed not simply at enhancing survival rates but also at improving the quality of survival by achieving better aesthetic results and reducing morbidity. That objective can be accomplished by means of so-called breast-preserving techniques. Large-scale international studies have produced evidence to their curative value.

Breast Neoplasms↗
PubMed1985

Bone metastasizing renal tumor (clear cell sarcoma) of childhood with epithelioid elements.

A case of bone metastasizing renal tumor (clear cell sarcoma) of childhood (BMRTC) is presented. Histologic examination demonstrated the typical histopathologic features of this type of tumor. In addition, epithelial cells were present which occurred in groups, either around a central eosinophilic core or occasionally around a small central lumen. To the authors' knowledge, the presence of epithelial cells in BMRTC has not been reported before. The histogenetic implication of this finding is discussed.

Bone Neoplasms↗
PubMed1985

Covalent labeling of functional states of the acetylcholine receptor. Effects of antagonists on the receptor conformation.

Photoaffinity labeling of membrane-bound nicotinic acetylcholine receptor from Torpedo marmorata electric tissue with the ion-channel blocker [3H]TPMP+ reveals various functional states of the receptor protein if labeling is performed with ms time resolution. In the resting and in the activated state most of the label is incorporated into the alpha-polypeptide chains of the receptor complex. When equilibrated with agonists and antagonists, predominantly the delta-polypeptide chain (and to a lesser extent the beta-chain) reacts with the photolabel. Reactivity of the delta-chain increases after exposure to cholinergic effectors with a half-life slower than the kinetics of receptor activation or rapid desensitization. Agonists and antagonists stimulate photolabelling of the delta-chain with different kinetics. For acetylcholine, carbamoylcholine and suberyldicholine the half-life of the reactivity increases is 400 - 500 ms; for the antagonists hexamethonium, d-tubocurarine and flaxedil it is about 10 s. The latter slow kinetics are also observed when the receptor is preequilibrated with agonists or antagonists prior to mixing with [3H]TPMP+ and starting the photoreaction. We conclude that time-resolved photoaffinity labeling can convalently mark protein structures involved in receptor functions. Of special interest is the observation that antagonists also induce a conformational change in the receptor protein.

Acetylcholine↗
PubMed1985

Malignant peripheral neuroectodermal tumours of childhood and adolescence.

Seventeen cases of malignant peripheral neuroectodermal tumour (MPNT) were studied by means of light microscopy, immunohistochemistry and electron microscopy. There were nine males and eight females. The mean age of the 17 patients was 10 years with a range of seven months to 20 years. The vast majority of tumours was located in the trunk. Histologically, they closely resembled Ewing's sarcoma, although minor differences were obvious. Special findings included ganglion cells and Flexner rosettes. In 10/11 cases positive staining for neuron-specific enolase (NSE) was obtained. Five of 10 tumours were positive for protein S-100. Three contained vimentin, two neurofilaments and one vimentin, neurofilaments and GFAP. Neurosecretory granules were noted in the three cases studied. Five patients died, three are alive with disease and five patients are alive without evidence of disease. It is concluded that these tumours form a homogeneous group, although the grade of differentiation varies. The prognosis in most cases is poor. Distinction from Ewing's sarcoma is possible by staining for NSE and by electron microscopy.

Adolescent↗
PubMed1985

Primary malignant hepatic tumours in childhood.

Twenty-four cases of hepatoblastoma, 14 cases of hepatocellular carcinoma and three cases of malignant mesenchymoma out of a total of 54 primary liver tumours were studied by light microscopy and immunohistochemistry. A remarkable finding in one case of hepatoblastoma and one case of hepatocellular carcinoma was a sarcoid-like reaction in the tumour tissue. Three cases of hepatoblastoma presented a macrotrabecular pattern. Among hepatocellular carcinomas, three cases corresponded to the fibrolamellar variant. By immunohistochemistry, the proportion of cases with positive staining for alpha 1-fetoprotein was higher in hepatoblastoma than in hepatocellular carcinoma. HBs-antigen could be demonstrated in non-neoplastic liver cells in two cases of hepatocellular carcinoma, but not in the tumour cells. No strong correlation between histological pattern and prognosis could be established in hepatoblastoma. However, there was a tendency to more aggressive biological behavior in cases with pronounced mitotic activity. The number of mitoses in hepatoblastoma varied widely. As in previous studies, patients with the fibrolamellar variant of hepatocellular carcinoma fared better than those with the classical type of this tumour. Prognosis in malignant mesenchymoma was not as poor as suggested from previous studies.

Carcinoma, Hepatocellular↗
PubMed1985

Entero-pancreatic reflexes revealed by duodenal anesthesia in the dog.

This study was designed to improve our understanding of duodeno-pancreatic reflexes, the existence of which was suggested by the previous observation of a reduction in secretin-stimulated pancreatic secretion during local anesthesia of the duodenal mucosa. The effects on this reduction in secretin-stimulated secretion of cholinergic or adrenergic blocking agents (alone or in combination) and of truncal vagotomy, were studied in conscious dog with gastric and pancreatic fistulae. For each agent and for secretin alone in normal and vagotomized dogs, a comparison was made of pancreatic secretion with and without lignocaine anesthesia of the duodenal mucosa. Lignocaine reduced pancreatic secretion with secretin alone, and stimulated it during infusion of atropine. The changes in both protein bicarbonate secretion were blocked by pentolinium and by phenoxybenzamine whereas propranolol mainly blocked the effects on bicarbonate output. The effect of truncal vagotomy resembled that of atropine. These results suggest the existence of two enteropancreatic reflex mechanisms; an excitory cholinergic vagal reflex and an inhibitory, atropine-resistant non-vagal reflex. Both are blocked by pentolinium (a ganglion blocker) and by phenoxy-benzamine, suggesting the involvement of alpha-adrenergic receptors probably also at the level of the ganglion cell. Beta-adrenergic receptors are also involved in the regulation of bicarbonate and fluid secretion.

Anesthesia↗
PubMed1985

Fibromatosis of infancy and childhood. Histology, ultrastructure and clinicopathologic correlation.

Fifty-nine cases of fibromatosis in children were investigated. To our knowledge, this is the largest serie with clinicopathologic datas reported so far in German literature. The most frequent type was infantile (desmoid-type) fibromatosis. More than 50% of the tumours developed in the first five years of life. The overall male-to-female ratio was 1.36:1. The lower extremities were the most frequent site of manifestation. Vimentin could be demonstrated in the tumour cells by immunohistochemical methods. Positive staining for dipeptidylaminopeptidase (DAP) IV suggested a myofibroblastic nature of some of the neoplastic cells. These results were supported by ultrastructural examination. Two cases demonstrated the unpredictable biological behaviour of fibromatosis. It is emphasized that clinical behaviour depends on number, size, location and histologic appearance of the lesions as well as age of the patient.

Arm↗
PubMed1985

Soft-tissue sarcomas in childhood. A study of 262 cases including 169 cases of rhabdomyosarcoma.

Although numerous investigations of soft-tissue sarcomas of childhood have been done, there are still many unsolved problems in the diagnosis, histogenesis, and biological behaviour of such tumours. In the present study, the soft-tissue sarcomas collected at the Paediatric Tumour Registry in Kiel were investigated. There was a total of 262 cases, including 169 (64.5%) in which a definite diagnosis of rhabdomyosarcoma had been made. An analysis of the age distribution showed that rhabdomyosarcoma is more than three times as frequent as non-rhabdomyosarcomatous soft-tissue tumours in the first quinquennium. Rhabdomyosarcoma exhibited male predominance (male-to-female ratio 1.45:1), whereas non-rhabdomyosarcomatous tumours showed an approximately equal sex distribution. Among the cases of rhabdomyosarcoma, the embryonal type clearly predominated (approx. 70%); the alveolar type was less common (approx. 20%). Correlation of histology with prognosis revealed that even tumours showing tiny foci with an alveolar pattern in otherwise solid, undifferentiated rhabdomyosarcoma, must be classified as alveolar rhabdomyosarcoma. Cases of alveolar rhabdomyosarcoma showed a higher incidence of local recurrence, lymph node metastasis, distant metastatic spread, and death, than did cases of embryonal rhabdomyosarcoma. It is concluded that "cytological differentiation" does not improve the prognosis of rhabdomyosarcoma.

Adolescent↗
PubMed1985

Comparative sensitivity of different methods to detect and quantify circulating fibrinogen/fibrin split products.

This study compared the sensitivity of three methods: staphyloccocal clumping test, SCT (Sigma and Calbiochem-Behring, CBC, reagents); Thrombo-Wellcotest (TWT); and Dade fibrinogen degradation products detection set, to quantify fibrinogen/fibrin split products (FSP) in blood samples from 696 patients and 124 normal donors using fibrinogen as the reference value. The Dade method gave quantitative results closely approaching the stated amount of fibrinogen. The SCT using Sigma reagents gave higher "fibrinogen" values, while the CBC reagents gave markedly lower "fibrinogen" values. The TWT detected only 25% of the fibrinogen standard. Detection of FSP following plasmin digestion of fibrinogen varied considerably for each test. The TWT, insensitive to most of the native fibrinogen, detected most of the FSP following only 15 minutes of plasmin digestion. In contrast, both assays relying on the SCT were completely negative after 24 hours of plasmin digestion. All four methods yielded FSP titers of less than 10 micrograms/mL in 97 (78.2%) of 124 blood samples from normal donors. The SCT Sigma reagents consistently gave results of less than 10 micrograms/mL in all normal donors. No instance of an FSP value greater than 40 micrograms/mL was noted for the 124 normal donors. Of the 696 patient blood samples tested, the Dade assay gave the highest or equally highest (with respect to another FSP method) value in 604 (87%) cases; the Sigma SCT did so in 360 (52%); the TWT in 316 (45%); and the CBC assay in 184 (26%) cases. The Dade test classified the largest number of blood samples, 328 (47.1%), in the greater than 10 less than 40 micrograms/mL titer category; however, the proportion of cases (32.2%) in which this test yielded values greater than 40 micrograms/mL was about the same as those produced by the Sigma SCT (29.9%) and TWT products (25.8%). Thus, with the exception of the normal (less than 10 micrograms/mL) and the suspicious (10-40 micrograms/mL) range, all three methods (Dade, Sigma, and TWT) are comparable in their abilities to detect abnormal levels of FSP. In the normal range, the Dade method will yield results that are frequently in the suspicious range. The CBC was noticeably inferior in detecting both suspicious and frankly abnormal values of FSP. Eight patients with acute leukemia were monitored sequentially with FSP and fibrinopeptide A (FpA) assays during their first course of chemotherapy. In all instances, elevated FpA levels correlated with elevated FSP values, as determined by the Dade, Sigma, or TWT assays.(ABSTRACT TRUNCATED AT 400 WORDS)

Agglutination Tests↗
PubMed1985

Febrile seizures in patients with complex partial seizures.

Febrile seizures occurred in 14 of 155 (9%) out-patients with complex partial seizures. Twelve patients had prolonged or recurrent febrile seizures, convulsive status epilepticus or a transient postictal neurological deficit. Febrile seizures were associated with perinatal abnormalities, an earlier onset of epilepsy and with a poor seizure control. Recurrent febrile seizures or those with complicating features are associated with an unfavourable therapeutic outcome in adult patients with complex partial seizures.

Adult↗