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S Weber

Publications and source records attributed to S Weber.

At least 415 records · Page 23Linked to original sources
PubMedDate not supplied

Influence of aspirin on the hemodynamic effects of sublingual nitroglycerin.

We studied the possible interaction between aspirin and nitroglycerin (NTG) in seven healthy volunteers. Effects of NTG (0.8 mg sublingual spray) were assessed by the decrease in diastolic arterial pressure, increase in heart rate, and decrease in M-mode echocardiographic end-diastolic and end-systolic diameters of the left ventricle. Measurements were performed before and during 30 min after NTG. Plasma levels of NTG were monitored during the experimental procedure. Each of the following trials was repeated three times, in random order, in each volunteer: NTG without aspirin pretreatment, NTG 1 h after 1 g of oral aspirin, and NTG after 8 days of aspirin, 500 mg every 48 h. Aspirin at the 1-g dose level significantly increased the effects of NTG on diastolic blood pressure (p less than 0.05) and left ventricular end-diastolic (p less than 0.001) and end-systolic (p less than 0.001) diameters. Aspirin (1 g) significantly increased (p less than 0.01) mean NTG plasma levels from 0.24 +/- 0.13 ng . ml-1 (control) to 0.37 +/- 0.26 ng . ml-1. We conclude that pretreatment with 1 g of aspirin increases NTG plasma levels and therefore significantly enhances the pharmacodynamic effects of NTG.

Adult↗
PubMedDate not supplied

Susceptibility of yeast isolates from defined German patient groups to 5-fluorocytosine.

Susceptibility and development of resistance to 5-fluorocytosine (5-FC) in Candida strains isolated from defined German groups of probands was investigated. 5-FC susceptibility was determined in a microdilution assay in yeast nitrogen base after 24 h of incubation at 37 degrees C. The range of 5-FC concentration investigated was between 0.015 and 16 micrograms ml-1. Isolates with a minimum inhibitory concentration (MIC) of > 16 micrograms ml-1 were regarded as 5-FC resistant. In total 335 Candida isolates were investigated, and 20 of them (6.0%) were found to be resistant. The Candida isolates were rather different with respect to their origin: out of 57 vaginal isolates from non-risk patients from Southern Germany 3.5% were 5-FC-resistant strains. One hundred and fifty-nine isolates from the urine of long-term intensive care patients from the whole of Germany showed 5-FC resistance (6.3%). Out of 74 isolates of different localization from intensive care patients of the University Clinics of Freiburg, 10.8% showed 5-FC resistance. Among 45 isolates from the oral cavity of HIV-positive patients from the Frankfurt region, no 5-FC-resistant strain was found. The epidemiology of 5-FC resistance is based mainly on the percentage of non-albicans isolates of the proband groups (C. tropicalis, C. krusei and others), and is less based on the frequency of Candida albicans serotype B isolates. In sequential observations with individual intensive care patients, no increase of 5-FC resistance in their Candida isolates could be observed with longer periods of hospitalization.

Candida↗
PubMedDate not supplied

Cultured porcine urinary bladder epithelial cells as a screening model for genotoxic effects of aromatic amines: characterisation and application of the cell culture model.

Isolated epithelial cells from porcine urinary bladders were maintained in dividing long-term monolayer cultures, and were used as a model system for the urinary bladder in toxicological studies in vitro. To examine the state of differentiation during the culture period, the culture system was characterised morphologically by light and transmission electron microscopy and by immune fluorescence labelling with antibodies against cytokeratins 7,13 and pan. The cultured cells were identified as urothelial epithelium by their polarised structure, and by their expression of several uroepithelial specific morphological features, such as fusiform vesicles, tight junctions and an asymmetric apical cell membrane. Additionally, the cells were labelled with anti-cytokeratin 7,13 and pan antibodies, and negatively with anti-vimentin antibodies. The maintenance of suitable culture conditions was shown by the stable enzyme activities of (gamma-glutamyltranspeptidase, alkaline phosphatase and acid phosphatase over a culture period of 4 weeks. A good viability of the cultured cells under the chosen culture conditions was shown by the presence of low amounts of lactate dehydrogenase (< of = 5%) in the culture medium. The activities of the chosen marker enzymes for cell differentiation (gamma-glutamyltranspeptidase), lysosomes (acid phosphatase) and luminal membranes (alkaline phosphatase) were relatively stable over the observed culture period. Enzyme activities involved in metabolism of xenobiotics were determined, to define the ability for metabolism in cultured cells compared with bladder tissue in situ. Several constitutive phase I and II enzyme activities were found to be stable during the culture period, indicating that the cultured cells should be able to metabolise xenobiotics in a comparable manner to the urothelium in vivo. The cytotoxic effects of xenobiotics were investigated and IC50 values were determined by means of lactate dehydrogenase leakage and inhibition of neutral red uptake. The induction of sister chromatid exchanges was used as a parameter for the genotoxic effects of several xenobiotics. This cell culture system was found to be a very good screening system for the testing of substances that affect the bladder, especially aromatic amines.

Amines↗
PubMedDate not supplied

Prostaglandin deficiency promotes sensitization of adenylyl cyclase.

Inhibition of prostaglandin synthesis by the drug indomethacin suppresses the synthesis of the cyclic AMP antagonist, prostaglandylinositol cyclic phosphate (cyclic PIP), and leads to a metabolic state comparable to type II diabetes. It was of interest whether prostaglandin-deficiency likewise causes sensitization of adenylyl cyclase, as this has been reported for the diabetic state. In liver plasma membranes of indomethacin-treated male rats, basal and forskolin-stimulated cyclic AMP synthesis remained unchanged when compared to untreated control rats. In control rats, stimulation of cyclic AMP synthesis by fluoride (2.2-fold) or glucagon (3.5-fold) was much lower than stimulation by forskolin (6.6-fold). In contrast, in indomethacin-treated rats, stimulation of cAMP synthesis by fluoride (4.6-fold) or glucagon (5.2-fold) nearly matched the stimulation by forskolin (6.4-fold). The level of alpha1-adrenergic receptors was slightly reduced, from 450 to 320 fmol/mg protein, by the indomethacin treatment. Independent of the treatment by indomethacin, stimulation of cyclic AMP synthesis by adrenaline failed, in agreement with the low density of adrenergic beta-receptors. In conclusion, PGE deficiency sensitizes adenylyl cyclase in rat liver for G protein-coupled receptors (glucagon) and also for fluoride.

Adenylyl Cyclases↗
PubMedDate not supplied

[Not Available].

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Germany↗
PubMedDate not supplied

[Is orthostatic circulatory regulation more difficult in multiple pregnancy? Results of a prospective longitudinal study].

In 7 multiple pregnancies the changes in maternal and fetal cardiac-circulation parameters resulting from a passive change in presentation from left lateral to steady upright were measured for the duration of pregnancy and the puerperium and compared with corresponding data from a single-fetus collective. The hypothesis that in multiple pregnancies the greater uterine contents lead to more severe problems of return flow from the lower extremities, and that these problems tend to lead a more pronounced form of uterovascular syndrome, was confirmed on the basis of the physiological data. The fact that the uterine contractions usually correlate with the maternal cyclic heart rate accelerations and peak toward the end of the third trimester of pregnancy supports the view that these contractions play a role in regulating circulation.

Blood Pressure↗
PubMedDate not supplied

Nifedipine and Raynaud's phenomenon associated with connective tissue diseases.

We have evaluated the therapeutic effect of the calcium-channel blocking agent nifedipine in Raynaud's phenomenon associated with connective tissue diseases and in idiopathic digital vasospasm. Thirty patients were included in this study: Raynaud's phenomenon was associated with progressive systemic sclerosis (PSS) in ten patients, systemic lupus erythematosus (SLE) in five and rheumatoid arthritis (RA) in three; it was idiopathic (I) in twelve patients. Each patient received, in a double-blind manner and random order, on two consecutive weeks, nifedipine (20 mg three times daily) and placebo. Nifedipine proved to be effective: the mean number of digital vasospastic attacks per week decreased from 20.30 to 5.83 (p less than 0.01). The results in the SLE and RA groups were similar and were pooled. The improvement (in percent decrease) was better in the idiopathic group (90.95) than in the SLE and RA group (78.63, p less than 0.02) and the PSS group (64.02, p less than 0.01).

Adult↗
PubMedDate not supplied

[Results of the psychologic evaluation of herniated disk patients. Personality structure and life status in relation to course].

32 patients with lumbar disc herniation were assessed by the Minnesota Multiphasic Personality Inventory (MMPI) and a psychiatric interview. After 1-2 years the final result was analysed. The MMPI profiles of the two groups with good or moderate to bad final result did not differ significantly and were within the normal range. The psychiatric evaluation showed in the majority of cases unusual personality factors. 23 of the 32 patients were in a critical life situation, so that it seems, that also in a disease with well known structural lesions, psychological factors may play a part in manifestation. The duration of the case history was markedly shorter in the group with moderate final result. After 1-2 years all patients except 1 were able to work or were retired. Gymnastics and sport were performed regularly only by about 1/3 of all patients.

Adaptation, Psychological↗
PubMedDate not supplied

[Physical therapy in geriatrics--possibilities and limits].

Physical therapy takes a great part in the rehabilitation of geriatric patients. Active exercise should stand in the first place. A good cooperation of the patient himself is required, also physical abilities and various interactions of different illnesses must be considered, when the aim of the treatment is determined. Passive physical modalities have a pain-relieving effect. It has to be considered that too many and too intensive applications of heat, hydrotherapy, and diathermy may cause an overstress for elderly patients. As a rule, physical therapy should be employed adequately. When the patient has attained a stable condition, individual therapy should be replaced by exercises in groups.

Aged↗
PubMedDate not supplied

Patient's evaluation and recall of the preoperative anaesthetic visit.

We have looked at the ability of 104 patients to recall their preoperative anaesthetic visit. 26.9% of those seen could not remember ever being assessed by an anaesthetist. We think this has important medical, medico legal and manpower implications which need to be addressed.

Adolescent↗
PubMedDate not supplied

[Hemodynamic assessement of the subendocardial perfusion (author's transl)].

Due to its purely diastolic perfusion pattern, the subendocardium is particularly sensitive to ischemia. The subendocardial perfusion can be hemodynamically assessed by the subendocardial viability ratio (EVR), ratio of the diastolic pressure-time index to the systolic pressure-time index. EVR may be either calculated in the catheterization laboratory or contimously monitorized in intensive care unit. Contimous EVR monitoring may prove useful in some critical hemodynamic states (cardiogenic shock, cardiac surgery) to asess the effects on subendocardial perfusion of the various proposed therapeutics either pharmacological (catecholamines, vasodilatators) or mechanical (intra-aortic baloon conterpulsation).

Aortic Valve↗