Search PubMed⌕ Search

Biomedical subjects

D Seiler

Publications and source records attributed to D Seiler.

At least 19 recordsLinked to original sources

Continuous telemetric monitoring of fetal oxygen partial pressure during labor.

INTRODUCTION: Upright or ambulatory birth positions are favorable for fetal oxygenation. Studies of fetal oxygenation with regard to maternal position require free maternal mobility. Therefore, telemetry for a fetal sensor for such investigations is a pre-requisite. Telemetry-if technically feasible-could enable monitoring of fetal oxygen partial pressure using an existing sensor without restricting the mobility of the parturient woman. We have developed a telemetry system for use with a fetal transcutaneous partial oxygen pressure sensor (ttcpO(2)) and have studied effects of maternal position and position changes during normal labor. MATERIALS AND METHODS: The monitoring system consists of three parts: the telemetry unit with the ttcpO(2) sensor to transmit the tcpO(2) and the heating output telemetrically, a modified CTG monitor and a personal computer storing the measurements. All data were plotted on the CTG recording paper and fed into a new purpose-designed software, displaying fetal heart rate, the uterine contraction intensity, ttcpO(2) and the heating output. Three laboring women, randomly and successively adopting "classical birth positions" (supine or side positions), sitting or vertical or walking position, were studied. RESULTS: Fetal heart rate, uterine contractions, ttcpO(2) and heating output are influenced by the birth positions and by changes of the birth position. In the classical supine and side position there seemed to be lower fetal oxygenation. Sitting, standing and especially walking were more favorable. DISCUSSION: Telemetry is useful to study a possible clinical benefit of individual birth positions.

Equipment Design↗

The impact of different intensities of regular donor plasmapheresis on humoral and cellular immunity, red cell and iron metabolism, and cardiovascular risk markers.

BACKGROUND AND OBJECTIVES: Major studies are still lacking on the impact of differing intensities of long-term donor plasmapheresis, not only on total serum protein, albumin and immunoglobulin G (IgG), but also on humoral and cellular immunity, red cell and iron metabolism, and biochemical cardiovascular risk markers. MATERIALS AND METHODS: Three groups of donors, comprising 483 individuals undergoing differing intensities of long-term serial plasmapheresis, were entered into a cross-sectional study. A fourth control group consisted of 100 non-donors. In addition to measuring total protein, albumin and IgG levels, we determined parameters of humoral and cellular immunity, red cell and iron metabolism and recognized biochemical cardiovascular risk factors. RESULTS: The median annual net amount of plasma donated by the three donor groups was 37, 16 and 10 l, respectively (P < 0.0001). Donors had significantly lower total serum protein, albumin and IgG levels than non-donors (P < 0.0001), but the intensity of plasmapheresis had no influence on those parameters. Like non-donors, all plasma donors had normal humoral and cellular immunity. No increased rates of iron store depletion were observed in the three groups of plasma donors. Plasma donors were not at increased cardiovascular risk. CONCLUSIONS: Regular donor plasmapheresis of up to 45 l of plasma per year appears to be as safe as more moderate plasmapheresis programmes, with respect to the parameters analysed in this study. Individuals donating under these conditions did not develop impaired humoral and cellular immunity, iron store depletion, or increased cardiovascular risk with regard to established biochemical risk markers. Prospective studies are required to determine more exactly than in retrospective analyses the reasons why donors withdraw from plasmapheresis programmes.

Adult↗

[Diagnosis of chronic prostatitis: 4 or 2 glass sample?].

Chronic pelvic pain syndrome is still an important clinical problem. The NIH-prostatitis classification introduced 1998 for diagnosis and treatment measures is based on extended microbiological analysis of urine, expressed prostate secretion (4-glass test), and ejaculate. We investigated if a simple urine analysis of an urine sample before and after prostatic massage (2-glass test) could replace the 4-glass test. 143 patients with the diagnosis chronic prostatitis were included in this prospective study. The results showed that the expensive and time consuming 4-glass test can be replaced by a simple 2-glass test. Extended examinations should only be performed in special cases.

Adult↗

[Four-glass or two glass test for chronic prostatitis].

Chronic pelvic pain syndrome is still an important clinical problem. The NIH prostatitis classification introduced in 1998 for diagnosis and treatment measures is based on extended microbiological analysis of urine and expressed prostate secretion (4-glass test). In 1997 J.C. Nickel proved that the culture and microscopic examination of urine before and after prostatic massage leads to the same results as the 4-glass test. In our prospective study on 143 patients with a diagnosis of chronic prostatitis, we analyzed this statement and came to the same results. We therefore recommend replacing the expensive and time-consuming 4-glass test by a simple preprostatic and postprostatic massage urine culture. Further examinations should only be performed in special cases.

Adult↗

Comparison of different cardiac markers in monitoring percutaneous coronary interventions with frequent use of stents and gpIIbIIIa-antagonists.

Studies from the early 1990s found elevations of creatine kinase (CK) and its isoform CK-MB in 5-30% of patients after PCI, indicating minor myocardial damage. Less is known about the influence of modern improved PCI-techniques on the frequency of elevated cardiac markers and the correlation between different commonly used markers, especially cardiac troponins. From 1997 to 2001, 1486 patients undergoing PCI during the regular working hours were included in the prospective "Ludwigshafen Infarctlet Registry". Myocardial infarction in the past 48 hours was an exclusion criterion. Clinical and procedural data were documented. Follow-up data were obtained from discharge up to one year. PCI-related elevations of troponin T were found in 18%, of total-CK in 11%, of CK-MB in 33% and of myoglobin in 23% of cases. The correlation between the different markers was poor. Compared with troponin T, other markers showed low sensitivity (total-CK 58%, CK-MB 27%, myoglobin 22%) and, especially total-CK, low specificity. Stenting, side branch occlusion or major dissection, complex lesion morphology, gpIIbIIIa-antagonist application, proximal stenosis and unstable angina were independent predictors of an elevated troponin T in multivariate analysis. Due to this weak correlation between more specific and sensitive troponins and the other markers, troponins are preferred in monitoring after PCI. In addition to lesion characteristics, particularly stenting is associated with an increased rate of elevated troponin.

Aged↗

Measurement of antithrombin activity by thrombin-based and by factor Xa-based chromogenic substrate assays.

Functionally active antithrombin can be quantified by chromogenic substrate assays utilizing the heparin cofactor activity of antithrombin and the inhibition rates of thrombin or of activated factor X (FXa). Thrombin-based assays but not FXa-based assays may overestimate the antithrombin activity due to their sensitivity toward heparin cofactor II. We focused on the question whether an overestimation of antithrombin activity by thrombin-based assays involves the risk of misdiagnosing antithrombin-deficient individuals as being non-deficient. We determined antithrombin using two thrombin-based assays and one FXa-based assay in 27 plasma samples from patients with acquired antithrombin deficiency spiked with lepirudin, in antithrombin-deficient plasma and in mixtures of antithrombin-deficient plasma and normal plasma. We also measured antithrombin in healthy subjects, in patients with inherited and acquired antithrombin deficiency and in patients under high-dose heparin treatment. At therapeutic final concentrations of lepirudin, antithrombin activities were considerably overestimated by the thrombin-based assays but not by the FXa-based assay. The residual antithrombin activities in antithrombin-deficient plasma determined by the thrombin-based assays were markedly higher than the corresponding values obtained with the FXa-based assay. The thrombin-based assays also overestimated antithrombin activity in patients under high-dose heparin. However, the degree of overestimation in the range between 50 and 100 IU/dl was too low to misidentify individuals with inherited or acquired antithrombin deficiency as normal. We conclude that functionally active antithrombin can be reliably determined using FXa-based chromogenic substrate assays in all settings examined. Thrombin-based assays must not be used in patients under treatment with hirudin or other direct thrombin inhibitors.

Adult↗

Development and evaluation of a reagent carrier with a new reaction sequence for the determination of creatinine in blood, plasma, serum and urine.

After a short outline of the history of creatinine determination methods we describe the development of a dry-reagent-carrier system for the reflometric determination of the creatinine concentration in blood, plasma, serum and urine (Reflotron Creatinine (new)). The method is based on a sequence of enzymatically catalyzed reactions producing H2O2, but which in contrast to the previously used procedure do not lead to the formation of creatine as an intermediate. Hence, pretreatment of sample material to eliminate endogenous creatine is no longer necessary. In the indicator reaction, use is made of an imidazole derivative as the chromogen. The dye formed in the presence of peroxidase can be measured by reflectance photometry beyond the long-wave absorption bands of haemoglobin and bilirubin at 642 nm. We present in detail the results of the multicentre evaluation of the analytical properties of this new test principle. The data obtained show that Reflotron Creatinine (new) correlates well with the routine method Creatinine PAP, which was used as a comparison method, with respect to accuracy and precision and even surpasses it with respect to specificity. Advantages over the first generation of Reflotron Creatinine are: shorter reaction time, longer stability of the reagent carrier, no interference by bilirubin and reduced interference by haemoglobin.

Blood Chemical Analysis↗

Biochemical, hematological and endocrinological parameters during repeated intense short-term running in comparison to ultra-long-distance running.

In order to see the differences in the acute effects of two kinds of running on biochemical, hematological and hormonal parameters, we investigated in one 24 h race (same exterior conditions) two groups of runners (NR = nonstop runners; RR = relay runners). From each participant blood samples were taken before, 3 times during and after the race. In both groups the lipid parameters cholesterol, triglycerides and LDL-cholesterol declined significantly, triglycerides even to 40% of their initial value, whereas HDL-cholesterol increased significantly. Renal parameters showed similar increases in both groups except for uric acid, which rose by 73% in RR compared with only 23% increase in NR. A difference was also found in the lactate and glucose concentrations, showing a four-fold increase and a 34% increase at 4 h respectively in RR, whereas the NR remained constant. Changes in the hematological parameters were similar in both groups. Cortisol and prolactin showed similar alterations during the race but LH and testosterone declined to approximately half of their initial concentration (p greater than 0.05) in NR after 4 to 8 h, in contrast to RR, where the concentration of LH or testosterone remained constant or changed only moderately but insignificantly during the race. Our investigation indicates that in ultra-long-distance running and intense short-term exercise performed under the same exterior conditions, many parameters show similar changes but great differences can be found as well if certain hormones, glucose metabolism and renal parameters are considered.

Adolescent↗

New method for the determination of pancreatic amylase evaluated.

We have carried out a multicenter evaluation of a new reagent carrier for Reflotron, specific for pancreatic amylase where the salivary isoenzyme is inhibited by two specific monoclonal antibodies. This new procedure combines easy handling with low imprecision (median CV less than 3%) in control material, serum, heparinized blood, and plasma) and close correlation (r = 0.991 to 0.999) with established manual and automated methods. The same close correlation was found with values obtained from either venous or capillary finger-stick blood. Salivary amylase up to 54 kU/L (37 degrees C) was inhibited to about 97%. Endogenous interference by hemoglobin, bilirubin, triglycerides, cholesterol, or hematocrit was found to be negligible within a wide range of interferent concentrations. Out of a panel of 28 commonly used drugs it was shown that only two (ascorbic acid and paracetamol), and then only at toxic concentrations, caused a deviation in amylase activity of greater than 10%. From the results of this study we conclude that this new method is suitable for highly precise and accurate measurements of pancreatic amylase in emergency and routine laboratories.

Amylases↗

Ultra-long-distance running and the liver.

During an ultra-long-distance race (1000 km in 20 days) the influence of running was examined on the enzymes aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), gamma-glutamyl-transferase (GGT), and glutamate dehydrogenase (GLDH) with regard to their release from the liver cells or their induction. Furthermore the liver synthetic capacity was assayed by measuring the enzyme activity of cholinesterase and the concentration of serum albumin during the race. Of the 110 participants, 55 finished the race and only the results of these runners were used in our study. AP increased continuously from day 0 (mean = 102 U/L) to day 19 (mean = 120 U/L). A fivefold increase of AST and a twentyfold increase of CK up to day 3 was followed by a significant decrease towards the end of the race. ALT rose as well up to day 6 from a mean value of 8 U/L to 24 U/L but remained at this level. Surprising was the individual increase of the enzymes GLDH (up to twentyfold) and GGT (up to sixfold) in more than half of the finishers on various days indicating liver cell injuries. The activity of CHE and the concentration of serum albumin decreased during the race, both were significantly correlated.

Adult↗

Effects of an ultra-long-distance (1000 km) race on lipid metabolism.

The influence was examined of ultra-long-distance running (1000 km race lasting 20 days) on changes in serum lipids. The 110 participants received two types of diet, a conventional Western diet and a wholesome vegetarian diet. Of the 55 finishers the serum concentration of total cholesterol, low density lipoprotein (LDL)-cholesterol, apolipoprotein B and triglycerides decreased significantly during the first 8 days of the run, but rose again towards the end of the race without reaching pre-race levels. The high density lipoprotein (HDL)-cholesterol increased initially but decreased in the final days of the run. The values for apolipoprotein A-I were not correlated with HDL-cholesterol. The free fatty acids and free glycerol showed marked increases (five times the prerace concentration), falling towards the end of the run. Changes in serum lipids showed no correlation with changes in body mass. Similar changes were observed in both dietary groups.

Adult↗

Effects of long-distance running on iron metabolism and hematological parameters.

In 110 well-trained participants of a 1000-km running competition lasting for 20 days hematological parameters, iron metabolism, and their respective changes during the race were investigated. Thirty-nine men and 11 women were accustomed to wholesome vegetarian food (lacto-ovovegetarian), 52 men and 8 women consumed a conventional western diet. In each group 50% of the runners finished the race. Before the competition started red blood cell count, hematocrit, and hemoglobin were on average below the values observed in the normal population in all groups. Both male and female runners consuming the wholesome diet showed significantly lower ferritin values than those on a western diet. During the first days of the competition hemolysis occurred leading to increased serum concentrations of bilirubin and iron and decreased haptoglobin levels. Hb concentrations showed a constant decrease during the race. Serum ferritin concentration rose about twofold within the first days and then decreased again without reaching pre-race levels. Serum iron concentrations showed a significant decrease between days 3 and 6. Iron loss was caused by hematuria (25% of all urines tested), gastrointestinal blood loss (10% of all stool specimens tested), and by sweating (4.5 micrograms iron/dl sweat). Our results suggest that especially in female long-distance runners it may be difficult to supply sufficient quantities of iron with the diet.

Adult↗

[Follow-up control after long-term withdrawal therapy in heroin and multiple drug addicts].

A follow-up study was done in 31 rehabilitation probands who were discharged consecutively from a long term drug withdrawal centre for heroin and multiple drug addiction. Referral had been on the basis of section 64 of the penal code and a motivation for treatment had to be established first. After discharge the majority of probands could be reassessed repeatedly. A total of 180 follow-up investigations included also urinanalysis and in 170 of these cannabinoids were looked for. Cannabis was detected in only two cases. When other addictives were demonstrated in a few cases they could be attributed to codeine-containing medicines beyond doubt. Regular follow-up assessments of past drug addicts including urinanalyses serve for further stabilisation of the patients and at the same time indicate long-term success of treatment.

Cannabinoids↗

[Acid phosphatase in blood (substrate: alpha-naphthylphosphate): reference values and diagnostic significance].

We report the results obtained with a modification of Hillmann's method (1) for determination of the catalytic concentration of acid phosphatase in serum using alpha-naphthylphosphate as the substrate. In a group of 158 males aged 16-85 years, the upper limit of the reference range (95th percentile) for the total acid phosphatase was established as 4.7 U/l (37 degrees C) and 4.2 U/l (30 degrees C), respectively; the corresponding values for the tartrate-inhibited acid phosphatase were 1.6 U/l (37 degrees C) and 1.5 U/l (30 degrees C). The upper limit of the reference range (95th percentile) for the total acid phosphatase determined in 60 females aged 18-80 years was 3.7 U/l (37 degrees C) and 3.0 U/l (30 degrees C). The catalytic concentrations in men and women did not show any age-related differences. The catalytic concentration of the tartrate-inhibited acid phosphatase was determined with the substrates alpha-naphthylphosphate and p-nitrophenylphosphate in a group of 89 patients with prostatic carcinoma (stages C and D). In 74 of these patients, the concentration of the prostatic specific acid phosphatase was assayed by enzyme-immunoassay and radioimmunoassay. The sensitivity of the method with p-nitrophenylphosphate was found to be unsatisfactory (66%), while that obtained with the other methods was superior and intercomparable (approx. 90%). The results obtained with the two substrates (p-nitrophenylphosphate vs. alpha-naphthylphosphate) differed significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid Phosphatase↗

Macrocreatine kinase in plasma: a cause for a false positive CK-MB immunoinhibition test.

The case of a patient with bronchial neoplasm is described. A non-typical form of creatine kinase found in the plasma gave rise to a false positive CK MB test by the immunoinhibition procedure. Electrophoresis on agarose gels beside a normal MM band showed an additional band between the MB and the MM band of a standard mixture. It could be shown by an immunoprecipitation test using precipitating antibodies against CK-MM and CK-BB that the creatine kinase of the abnormal band consists entirely of the MM-type, which after treatment with polyethylene glycol not only became susceptible to inhibiting anti-M antibodies, but also showed the electrophoretic motility of CK-MM. Gel filtration chromatography clearly demonstrated the macromolecular nature of this abnormal creatine kinase.

Catalysis↗