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Biomedical subjects

K Lehmann

Publications and source records attributed to K Lehmann.

At least 19 recordsLinked to original sources
PubMed1992

Species and sex differences of aflatoxin B1-induced glutathione S-transferase placental form in single hepatocytes.

Species and sex differences of aflatoxin B1 (AFB1)-induced glutathione S-transferase placental form (GST-P) positive single hepatocytes have been investigated 48 h after an intraperitoneal injection of AFB1 to young male and female Fischer rats (2 mg AFB1/kg body wt) and male Syrian golden hamsters (6 mg AFB1/kg body wt). The presence of GST-P positive hepatocytes was examined by the immunohistochemical method. Male rats formed three times as many AFB1-induced GST-P positive hepatocytes as females. Pretreatment of both male and female rats with an inhibitor of GSH synthesis, buthionine sulfoximine (BSO) (4 mmol/kg body wt), 2 h and 4 h before AFB1 injection increased AFB1-induced GST-P positive hepatocytes by about 120% above the controls. Male hamsters formed several-fold less AFB1-induced GST-P positive hepatocytes than male rats. Pretreatment with BSO did not increase AFB1-induced GST-P positive hepatocytes in hamsters even though it produced an increase in hepatic necrosis. It appears that GSH and GSH S-transferases play an important role in modulating hepatic AFB1-DNA binding and AFB1-induced GST-P positive hepatocytes in rats and hamsters.

Aflatoxin B1↗
PubMed1992

[Fewer negative appendectomies thanks to improved clinical diagnosis].

108 consecutive patients presenting with suspected acute appendicitis were studied prospectively. To improve clinical performance, 19 clinical criteria were evaluated. For cases with unclear diagnostic situations laparoscopy was performed. With 10 of the above mentioned criteria the score published by de Dombal, which can reach a maximal value of 7 points, was calculated. For data processing the rate of negative appendectomies as well as the de Dombal score were used. 61 appendectomies with 7 (11.5%) perforations, 48 (78.7%) acute inflammations and 6 (9.8%) normal appendices have been performed. 39 (36.1%) patients with non-specific abdominal pain were observed for 3 +/- 2 days before discharge, while 7 (11.5%) had another surgical disease. In the appendectomized patients the score was 4.3 +/- 1.1 with perforation, 4.4 +/- 1.0 with acute inflammation and 3.8 +/- 1.3 with a normal appendix (p = ns). The score for non-specific abdominal pain in patients not undergoing surgery was significantly lower (2.2 +/- 1.2; p less than 0.01). Patients with other surgical diseases had a score of 3.1 +/- 1.1 with no significant difference from patients who had undergone appendectomy or from those with non-specific abdominal pain. Laparoscopy was performed in 16 (14.8%) patients. 9 patients had appendicitis, 4 non-specific abdominal pain and 3 another surgical disease. Improved clinical examination significantly (p less than 0.05) reduced negative appendectomies from 20.3% to 9.8% without a rise in the rate of perforation due to prolonged observation. The 6 patients with negative appendectomy could not be identified even by improved clinical examination.

Acute Disease↗
PubMed1992

[Negative appendectomies can be decreased by improved clinical assessment alone].

We had a 20% rate of negative appendectomies in our patients presenting with suspected appendicitis. We suggested that an improved clinical examination would reduce this rate. 84 consecutive patients presenting with suspected acute appendicitis were prospectively studied. 10 clinical features were used to calculate a score which should distinguish appendicitis and non-specific abdominal pain. 53 appendectomies with 6 (11.3%) perforations, 41 (77.4%) acute inflammations and 6 (11.3%) normal appendixes have been performed. 26 patients suffered from non-specific abdominal pain, 5 had an other surgical disease. In the appendectomized patients the score was 4.2 +/- 1.2 with perforation, 4.4 +/- 1.1 with acute inflammation and 3.8 +/- 1.3 with a normal appendix (p = ns). The score for non-specific abdominal pain in patients without operation was significantly lower (2.0 +/- 1.1; p less than 0.01). Patients with other surgical disease had a score of 2.8 +/- 1.5 with no significant difference to patients which had undergone appendectomy. Negative appendectomies were reduced by improved clinical examination from 20.3% to 11.3% without change in the rate of perforation. The remaining patients with negative appendectomies could not be identified by improved clinical examination even by means of the score. But the use of the score improved the performance of the clinicians.

Abdomen, Acute↗
PubMed1992

[Incidence of local complications after heart catheter studies and their imaging with intravenous digital subtraction angiography: a retro- and prospective study].

Frequency of local complications following punction of the femoral artery aimed to cardiac catheterisation has been checked with 1051 patients retrospectively as well as 300 patients prospectively. Intravenous DSA was carried out when symptoms like stenotic murmurs, pulsations, hematoma, swelling or resistance within the concerned inguinal region appeared with suspicion diagnose of pseudoaneurysm, arteriovenous fistula or any other complications of vessels. The retrospective study reviewed a rate of complications of 1.62% and the prospective study a rate of 2.7%. The study reviewed that by using of DSA-checkings during a time period of 4 up to 10 month later no rest aneurysm or AV-fistula could be proved. That means a spontaneous thrombose took place with patients without operation indication. Significant connections were found between clinical pathological findings next to the position of punction and the occurrence of local complications. The single symptoms like stenotic murmurs or large hematoma are statistically proved indications to a complication of vessel. There is no connection between findings like pseudoaneurysm or AV-fistula and small hematomas next to the punction position. The intravenous DSA has been proved as easy and proof method with a small quantity of complications for the inclusion and differentiation of local complications following punction of the artery femoral.

Adult↗
PubMed1991

[Clinical examination remains the most important part of the diagnosis in suspected appendicitis].

This paper reports why the rate of unnecessary appendectomies can not be reduced exclusively by selected diagnostic laparoscopy. 75 women and 94 men greater than or equal to 16 years of age which had undergone appendectomy and/or diagnostic laparoscopy were analyzed for 19 clinical criteria in a retrospective study. We operated on 26 (17.0%) perforated, 100 (65.4%) acutely inflamed and 27 (17.6%) normal appendixes. 29 diagnostic laparoscopies showed 16 normal and 13 inflamed appendixes. 60 to 66% of the criteria had been evaluated. Important confirmatory signs and symptoms which would have allowed to establish a diagnosis had been overlooked very often. We did not find any sign or symptoms with discriminatory value. We conclude that a major cause of unnecessary appendectomies and imprecise indications for laparoscopy has been incomplete preoperative clinical examination.

Adolescent↗
PubMed1991

Pharmacokinetics and converting enzyme inhibition after morning and evening administration of oral enalapril to healthy subjects.

Possible circadian changes in the pharmacokinetics and effect on serum angiotensin-converting enzyme (ACE) activity of the ACE inhibitor enalapril have been studied in 8 healthy subjects after oral ingestion of 10 mg enalapril maleate either at 08.00 h or 20.00 h. The time to peak serum concentration (tmax) of enalapril was increased after administration at 20.00 h compared to 08.00 h (2.4 h versus 1.3 h), whereas other kinetic parameters were not significantly altered. The 24 h-kinetics of the active metabolite enalaprilat did not differ significantly between the two treatments, but the area under the curve (AUC (0-24] and the peak serum concentration (Cmax) were slightly higher after intake at 20.00 h. The relationship between the measured serum enalaprilat level and the degree of inhibition of serum ACE was the same after both treatments. Overall, the evening and morning administration of enalapril did not differ markedly in the pharmacokinetics and the time course of ACE inhibition.

Administration, Oral↗
PubMed1991

First dose hypotension with enalapril and prazosin in congestive heart failure.

Since the introduction of angiotensin converting enzyme inhibitors into the adjunctive treatment of patients with congestive heart failure, cases of severe hypotension, especially on the first day of treatment, have occasionally been reported. To assess the safety of the angiotensin converting enzyme inhibitor enalapril a multicenter, open, randomized, prazosin-controlled trial was designed comparing the incidence and severity of symptomatic hypotension on the first day of treatment. Trial medication was 2.5 mg enalapril or 0.5 mg prazosin. Subjects were 1210 inpatients with New York Heart Association functional class (I)/II and III who were not adequately compensated with digitalis and/or diuretics. In the group receiving enalapril, 3 patients (0.5%) experienced severe hypotension on day 1 and 28 patients (4.7%) moderate hypotension. In those given prazosin, 15 patients (2.6%) experienced severe hypotension and 60 patients (10.3%) moderate hypotension. The difference is statistically significant (P less than or equal to 0.000012). All patients recovered. It was concluded that treatment of patients suffering from congestive heart failure New York Heart Association functional class (I)/II or III with enalapril is comparably well tolerated.

Aged↗
PubMed1991

Intravascular ultrasound imaging of human coronary arteries in vivo. Analysis of tissue characterizations with comparison to in vitro histological specimens.

BACKGROUND: Intravascular ultrasound imaging was performed in 27 patients after coronary balloon angioplasty to quantify the lumen and atheroma cross-sectional areas. METHODS AND RESULTS: A 20-MHz ultrasound catheter was inserted through a 1.6-mm plastic introducer sheath across the dilated area to obtain real-time images at 30 times/sec. The ultrasound images distinguished the lumen from atheroma, calcification, and the muscular media. The presence of dissection between the media and the atheroma was well visualized. These observations of tissue characterization were compared with an in vitro study of 20 human atherosclerotic artery segments that correlated the ultrasound images to histological preparations. The results indicate that high-quality intravascular ultrasound images under controlled in vitro conditions can provide accurate microanatomic information about the histological characteristics of atherosclerotic plaques. Similar quality cross-sectional ultrasound images were also obtained in human coronary arteries in vivo. Quantitative analysis of the ultrasound images from the clinical studies revealed that the mean cross-sectional lumen area after balloon angioplasty was 5.0 +/- 2.0 mm2. The mean residual atheroma area at the level of the prior dilatation was 8.7 +/- 3.4 mm2, which corresponded to 63% of the available arterial cross-sectional area. At the segments of the coronary artery that appeared angiographically normal, the ultrasound images demonstrated the presence of atheroma involving 4.7 +/- 3.2 mm2, which was a mean of 35 +/- 23% of the available area bounded by the media. CONCLUSIONS: Intravascular ultrasound appears to be more sensitive than angiography for demonstrating the presence and extent of atherosclerosis and arterial calcification. Intracoronary imaging after balloon angioplasty reveals that a significant amount of atheroma is still present, which may partly explain why the incidence of restenosis is high after percutaneous transluminal coronary angioplasty.

Angiography↗
PubMed1991

[Diagnosis of "fatal ethanol poisoning in the absorption phase"].

In cases of disputed fatal alcohol intoxication during the absorption (pre-peak) period it is strongly recommended to examine the blood ethanol level not only in blood taken from a peripheral vessel but also simultaneously in blood from at least one central. In the case reported, without such a duplex determination of the blood ethanol concentration it would have been impossible to establish the actual cause of death.

Aged↗
PubMed1991

Design and analysis of the HYPREN-trial: safety of enalapril and prazosin in the initial treatment phase of patients with congestive heart failure.

Since the introduction of angiotensin converting enzyme (ACE) inhibitors into the adjunctive treatment of patients with congestive heart failure, cases of severe hypotension, especially on the first day of treatment, have occasionally been reported. To assess the safety of the ACE inhibitor enalapril a multicenter, randomized, prazosin-controlled trial was designed that compared the incidence and severity of symptomatic hypotension on the first day of treatment. Trial medication was 2.5 mg enalapril or 0.5 prazosin. Subjects were 1210 inpatients with New York Heart Association (NYHA) functional class II and III. Patients who received enalapril experienced clinically and statistically significantly less symptomatic hypotension (5.2%) than the patients who received prazosin (12.9%). All patients recovered. It was concluded that treatment with enalapril was well tolerated and it is, therefore, unreasonable to restrict the initiation of treatment with enalapril to inpatients.

Aged↗
PubMed1990

The effect of complete and incomplete revascularization on exercise variables in patients undergoing coronary angioplasty.

To investigate the effects of complete and incomplete revascularization on the response to exercise, 25 patients underwent symptom-limited exercise testing with continuous assessment of gas exchange a mean of 5 +/- 4 days prior to and 18 +/- 12 days following percutaneous transluminal coronary angioplasty. All antianginal medications were discontinued for testing. Revascularization was considered complete if all stenoses were reduced to less than 50% diameter (13 patients), and incomplete if one or more stenoses remained (12 patients). Consistent improvements in ST-segment depression were observed after angioplasty at matched submaximal exercise levels (mean range 0.5-0.8 mm; p less than 0.05), and were accompanied by a reduction in angina. Significant increases in heart rate and systolic blood pressure were observed at peak exercise following angioplasty in both groups. Gas exchange variables were significantly improved at maximal exercise, with a similar increase in oxygen uptake observed in both groups following angioplasty (mean increase 3.3-3.7 ml/kg/min; p less than 0.01). Thus, incomplete revascularization following coronary angioplasty resulted in hemodynamic, electrocardiographic, symptomatic, and gas exchange responses to exercise that were comparable to complete revascularization.

Adult↗
PubMed1990

The issue of the core syndrome of endogenous depression.

The psychopathological findings in 339 patients treated for depressive disorder were investigated. The classification was made according to ICD 9 and DSM III. The classification and diagnosis of depressive disorders are based on the symptoms, etiology and the course of the disease. Therefore we aim at a three-dimensional scheme of classification that takes into account all these variables. We do not want to follow the basic problems of classification and all dimensions of depressive disorders. We just want to analyze our psychopathological findings in depressive patients, who have been classified according to ICD 9 and DSM III, and we want to turn our attention to the core syndrome of endogenous depression.

Adjustment Disorders↗
PubMed1985

A monoclonal lambda 1-bearing anti-dextran antibody from a lambda-defective mouse strain.

A hybridoma from the lambda-defective mouse strain SJA has been established. It produces a lambda 1-bearing IgG2b, dextran B 1355-binding antibody. The DNA sequence of the VJ and C gene segment was in complete accordance with the published germ-line sequence. The rate of secretion and the steady state level of cytoplasmic RNA of this line was comparable to that of cell lines from normal mice. The idiotype was closely related to that of MOPC 104E indicating that the lambda 1 light chain is associated with the same VH region and in a similar fashion as in BALB/c mice. This antibody should be useful for further experiments on the lambda defect of SJL or SJA mice.

Animals↗
PubMed1979

[Effect of psychotropic drugs on somatosensory evoked cortical potentials].

The effects of some typical clinically tested psychotropic drugs were studied in acute experiments on awake rats. Potentials in somatosensory cortex were evoked by peripheral stimulation. Haloperidol, diazepam, medazepam, desipramin and a new substance, the MPP-sulton, caused significant modification in latency and amplitude of some components of the potentials. Between the effects of psychotropic drugs exist differences which, in turn, were clearly distinguishable from the modification of these evoked responses by unspecific narcotic effects of hexobarbital.

Animals↗
PubMed1979

[Pharmacological modification of evoked caudate nucleus potentials].

To stimulation of the Substantia nigra the nucleus caudatoputamen of the rat responds with the release of a short-latent sum action potential that may serve to characterize the interaction between the two nuclear areas. The partly conflicting results reported in the literature about drug effects on this potential prompted us to examine the effectiveness of dopaminergic and cholinergic substances or their antagonists following systematic administration. Chloropromazine increases the amplitude of the potential, while apomorphine has a distinct antagonistic effect. Interesting appear to be the analogical effects of Tricuran, arecoline and apomorphine, and the furtherance of the chloropromazine effect by arecoline.

Animals↗
PubMed1978

[The problem of the Romano-Ward syndrome--misinterpretation as genuine epilepsy].

It is reported on a case of Romano-Ward-syndrome in a 40-year-old female patient. The problems of the most frequent false interpretation as idiopathic epilepsy as well as the differential-diagnostic considerations concerning the exclusion of symptomatic QT(U)-elongations in the ECG are entered. The pathomechanisms which perhaps are the basis of the syndrome are discussed.

Adrenergic beta-Antagonists↗
PubMed1978

[Problems in splenic cysts--a case contribution].

It is reported on a cyst of the spleen in a twenty-nine-year-old female patient in whom as accidental findings a splenomegaly was established. The diagnosis would be ascertained by means of laparoscopy and laparotomy. The genesis of the cyst remained unclear. The author deals with the problems of the differential diagnosis.

Adult↗