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U Stein

Publications and source records attributed to U Stein.

At least 19 recordsLinked to original sources
PubMed1992

Comparison of the effects of losigamone and its isomers on maximal electroshock induced convulsions in mice and on three different patterns of low magnesium induced epileptiform activity in slices of the rat temporal cortex.

Losigamone (AO-33) is a recemate of a tetronic acid derivative. The effects of losigamone and its three isomers (AO-242, AO-294 and AO-23) were compared on maximal electroshock (MES) induced convulsions in mice and on different patterns of extracellularly recorded, low Mg2+ induced epileptiform activity in slices of the rat temporal cortex. Lowering Mg2+ induced recurrent short discharges in areas CA3 and CA1 while ictaform events that lasted for many seconds were induced in the entorhinal cortex. In the hippocampus the activity stayed stable over a number of hours. In contrast, the ictaform events in the entorhinal cortex changed their characteristics after one to two hours to recurrent discharges of 0.8 to 10 s. Afterdischarges and interictal events were absent. 50 microM AO-242 showed a similar efficacy to 50 microM AO-33 in reducing and blocking epileptiform discharges in areas CA1 and CA3 while 50 microM AO-294 and 50 microM AO-23 had weaker effects than 50 microM AO-33. Concentrations of 50 microM and 100 microM AO-242 showed a similar efficacy to AO-33 on ictaform events in the entorhinal cortex. Late recurrent discharges were also blocked by AO-33 and AO-242 although at higher concentrations (300 microM). The in vitro observations are with respect to order of efficacy in accordance with the in vivo data obtained in the maximal electroshock test in mice. The order of potency in the MES test was AO-242 greater than AO-33 much greater than AO-294 much greater than AO-23.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Spontaneous splenic rupture in chronic pancreatitis].

A 50-year-old woman complained of upper abdominal pain for several weeks, getting worse and radiating towards the left shoulder in the 24 hours preceding her hospital admission. Plain X-ray film of the abdomen revealed plaque-like calcifications projecting onto the tail of the pancreas. Ultrasound imaging demonstrated splenic rupture with free intra-abdominal fluid. During an emergency laparotomy the spleen was removed. At first the postoperative course was uneventful. But epigastric pain recurred a few days after discharge. Serum amylase and lipase concentrations were elevated (280 U/l and 553 U/l, respectively). Endoscopic retrograde cholangiopancreatography revealed chronic pancreatitis with a 3 cm pseudocyst in the tail of the pancreas. A papillotomy was performed, after which the symptoms rapidly regressed and the pancreatic enzyme concentrations fell. This was thus a case of spontaneous splenic rupture associated with previously undiagnosed chronic pancreatitis with inflammatory papillary stenosis and pseudocyst in the pancreatic tail.

Abdominal Pain↗
PubMed1991

Losigamone.

Explore the source record for details and available documents.

Animals↗
PubMed1990

Induction kinetics of delayed fluorescence of sun and shade leaves of Fagus sylvatica in the ms-range.

Induction kinetics of luminescence (= delayed chlorophyll fluorescence or delayed light emission) were measured with sun and shade leaves of a tall beech tree (Fagus sylvatica 'pendula', weeping beech). The kinetics detected in the ms-range are contrasted for the upper and the lower leaf side. The influence of the following parameters is demonstrated: time of dark-adaptation prior to the measurement, intensity of the excitation light and photoinhibitory treatment. The effects are discussed with respect to chlorophyll concentration, absorption of the excitation light, reabsorption of the luminescence and photosynthetic activity of the leaf tissue. It is shown that the luminescence signal and its kinetic are determined mainly by the properties of the mesophyll parenchyma facing the detector. Thus the more densely packed palisade parenchyma at the upper leaf side exhibits a lower luminescence and a slower kinetic than the spongy parenchyma at the lower leaf side, which is characterized by many aerial interspaces. Our study shows that luminescence kinetics can be applied to interpret the physiological state of a specific leaf tissue. They may serve as an indicator of disorders in the photosynthetic function.

Kinetics↗
PubMed1989

[Juxtapapillary gangliocytic paraganglioma of the duodenum].

A juxtapapillary duodenal polyp (measuring 1.5 x 1.0 x 1.2 cm) was removed endoscopically in a 57-year-old man who had had recurrent intestinal bleedings. Histological examination revealed a typical duodenal gangliocytic paraganglioma with carcinoid and paraganglioma-like components, as well as neuroid portions with ganglion cells. Various neuroendocrine markers (neuron-specific enolase, chromogranin, protein-gene product 9.5) were demonstrated immunohistochemically. Tests for pancreatic polypeptide, substance P, enkephalin, cholecystokinin, glucagon and S-100 proteins, were all positive.

Ampulla of Vater↗
PubMed1989

[Spontaneous arteriovenous shunt in chronic arterial occlusive disease of the lower extremities. A nuclear medicine study].

For radionuclide assessment of AV-shunting Tc99m aggregated albumin microspheres were injected into the proximal femoral artery in 10 patients with chronic peripheral OAD and a visualized proximal AV shunt during percutaneous transluminal angioplasty. Isotope activity in the lungs and the afflicted leg was investigated with a computer-linked whole body scanner. 12 patients undergoing the same treatment but without proximal AV shunt and one healthy volunteer served as control group. In this group 6 patients suffered from longtime diabetes. Patients with visualized AV shunts showed a significant higher isotope activity in the lungs than non-diabetics without proximal shunts. To our surprise diabetics without proximal AV fistula proved to have also a significant augmented pulmonary activity. Pathophysiological conditions for the evolution of proximal and peripheral AV shunts in patients with chronic OAD are discussed. The poor response to local clot lyses in patients with radionuclide prove of AV shunts underlines their hemodynamic importance under clinical aspects.

Aged↗
PubMed1988

Evaluation of a novel Bayesian method for individualizing theophylline dosage.

A novel Bayesian drug dosing program (Abbott Pharmacokinetic Systems, Theophylline Program) was evaluated. The predictive accuracy of this method was assessed in 10 healthy volunteers receiving single intravenous test doses. Estimates for clearance and distribution volume were compared with those obtained from the area under the curve. The observed prediction error depended largely on sampling time. The deviations were lowest for the distribution volume during the first 60 min and for clearance at 12 hours after theophylline administration. Furthermore the Bayesian technique was prospectively evaluated in 10 hospitalized and 22 outpatients treated with sustained-release theophylline preparations (Uniphyllin, Bronchoretard, PulmiDur). Predictive precision and accuracy were adequate, if theophylline was given twice daily. The highest predictive accuracy was achieved in outpatients, if predictions were based on trough concentrations. In 19/22 outpatients prediction errors were within a clinically acceptable range (mean prediction error +/- standard deviation; -0.6 +/- 2.1 mg/l). Moreover in hospitalized patients (n = 5) with twice-daily maintenance regimens, concentration-time curves could mainly be predicted with sufficient accuracy. Hospitalized patients (n = 5) with once-daily dosing showed large fluctuations between peak and trough theophylline concentrations in serum. In these patients a reliable prediction of the concentration-time curves was not possible apparently due to non-linearity of theophylline kinetics. Relatively large prediction errors were found in one patient with acute viral respiratory illness and 3 patients with altered absorption. Despite certain limitations the clinical application of the Bayesian forecasting method tested appears to be promising.

Adult↗
PubMed1987

Biochemical and immunological characterization of structural proteins from retrovirus-D/New England and comparison to Mason-Pfizer monkey virus and permanent human fibroblast virus.

Biochemical and immunological properties of retrovirus-D/New England (here referred as R-D/NE) recently isolated at the New England Regional Primate Research Center, Southborough, Ma, from a rhesus monkey with acquired immune deficiency syndrome were investigated and compared to the prototype type D retroviruses Mason-Pfizer monkey virus (MPMV) and permanent human fibroblast virus (PMFV) isolated from a breast carcinoma of a rhesus monkey and a continuous human cell line, respectively. The polypeptide composition of R-D/NE propagated in a human lymphoid B cell line (Raji cells) has been investigated using SDS-polyacrylamide gel electrophoresis. Staining with Coomassie blue and labelling with 14C amino acids revealed seven viral polypeptides with molecular weights of 4,000, 10,000, 12,000, 15,000, 18,000, 27,000, and 80,000 Da which were also shared by MPMV and PMFV. The 80,000 Da protein was shown to be a glycoprotein by incorporation of 3H glucosamine. The 18,000 Da protein was identified as a phosphoprotein of R-D/NE. p18 structural proteins of MPMV and PMFV represent phosphoproteins of their respective viruses as well. All three phosphorylated proteins contain O-phosphoserine as major phosphoamino acid. The comparison of tryptic peptide maps of the major internal structural proteins of R-D/NE, MPMV, and PMFV revealed a striking similarity among p 10/p 12 and p 15. proteins. A minor difference was detected among the tryptic peptide digests of p 4 and p 27 proteins. Antiserum against p 15 of MPMV showed a significantly weaker binding to R-D/NE than to MPMV and PMFV at high dilutions.

Amino Acid Sequence↗
PubMed1979

[Pharmacological treatment of chronic arterial occlusive disease (author's transl)].

Two thirds of the patients with peripheral arterial occlusive disease have to be treated conservatively, for only up to 30% can be revascularized by operative methods. Using the pharmacological differential treatment the grade of compensation and localization of the obliterative process has to be considered. Ignoring the usual basic therapy (elimination of heart failure and pathological bradycardia, systemic walking-exercise, anticoagulation etc.) intrafemoral long-term application of energetic phosphate (i.e. nucleotid-nucleosid-mixtures) leads to a positive result in nearly two thirds (n = 97 legs) with a degree of II to IV of Fontaine. Whereas the snakes' encyme Ancrod with the effect of defibrination was successful in almost 70% of the patients with arterial insufficiency (n = 45) including the degree II B (painless walking-distance under 100 meters). Energetic phosphates, applied to the arteria femoralis, are most successful in degree II with claudication intermittens. Ancrod should be used respectively for patients with pain during rest. These results are discussed with respect to compensation and localization of arterial occlusive disease, acute and chronic measurements of the hemodynamics by use of Doppler ultrasound and strain gauge plethysmography and with respect to variation of the concentration of the metabolic parameters lactate and pyruvate--the latter when defibrination was performed.

Aged↗
PubMed1978

Effect on vitamin A on the development of galactosamine-induced hepatitis in rats.

In order to elucidate the role of lysosomes in experimental hepatitis caused by D-galactosamine in rats the activities of cathepsin A and D and acid carboxypeptidase were measured. Enzyme activities were assayed in liver homogenate, lysosomal supernatant fraction and lysosomal sediment fraction. Lysosomal enriched fractions were prepared according to De Duve. Vitamin A in high doses aggravates the morphological alterations observed in galactosamine treated rats. At the same time the labilization of lysosomes increases substantially. This effect was induced by doses of retinyl-palmitate that normally caused only an activation of Kupffer cells and no significant liberation of lysosomal peptidehydrolases. The activities of cathepsin A and D increased 2-fold in liver homogenate after combined treatment with galactosamine and vitamin A, whereas the activity of acid carboxypeptidase decreased markedly.

Animals↗