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T Bertsch

Publications and source records attributed to T Bertsch.

At least 37 records · Page 2Linked to original sources
PubMed2000

Evaluation of a new simple and rapid enzyme-linked immunosorbent assay kit for neopterin determination.

A new commercially available enzyme-linked immunosorbent assay (ELISA) kit has been evaluated for the measurement of neopterin concentrations in serum, plasma and urine. This competitive ELISA is technically simple, requires only small sample volume and is rapid to perform. The assay procedure consists of sequential 1.5 h and 10 min room temperature incubation steps. The ELISA is accurate, sensitive, specific, and precise. Linear regression analysis of neopterin concentrations measured with the new ELISA and with an established method yielded a highly significant correlation (r = 0.99). The new assay is applicable to ELISA workstations, thus enabling determination of neopterin in large series of samples. The neopterin ELISA kit has been used in routine laboratory testing of blood donations in a blood bank.

Antibody Specificity↗
PubMed1999

Interferon-gamma-inducing factor (IL-18) and interferon-gamma in inflammatory CNS diseases.

OBJECTIVE: To examine the intrathecal production of a newly identified cytokine, interferon-gamma-inducing factor (IL-18), together with interferon-gamma itself, in inflammatory diseases of the CNS (i.e., bacterial meningitis, viral meningoencephalitis, and MS). RESULTS: IL-18 concentrations in CSF were significantly increased in bacterial meningitis and tended toward increased levels in viral meningoencephalitis. In contrast, IL-18 was detectable only in a few patients with MS and healthy controls. Interestingly, interferon-gamma was significantly increased selectively in CSF of patients with viral meningoencephalitis. CONCLUSION: The observation of an intrathecal release of IL-18 in patients with meningitis argues for a pathophysiologic role of this novel cytokine in immunity against invading microorganisms the CNS.

Adult↗
PubMed1999

Compatibility of plastics with cytotoxic drug solutions-comparison of polyethylene with other container materials.

In this study low density polyethylene (LDPE)-containers were compared to glass bottles and polyvinyl chloride (PVC) bags in view of adsorption effects with antineoplastic drugs. The infusion containers were supplemented with therapeutic doses of the nine common cytotoxic drugs carboplatin, carmustine, cytarabine, dacarbazine, fluorouracil, gemcitabine, melphalan, methotrexate and vinorelbine. 0.9% isotonic sodium chloride solution and 5% dextrose served as infusion solutions. The containers were stored at room temperature or at 4 degrees C, protected from light, for periods of up to 168 h. Turbidity, change of colour and visible crystallization were not observed. Samples were collected at different time intervals and drug contents were determined with high-performance liquid chromatography (HPLC). Preparations of carmustine showed no adsorption phenomena when stored in LDPE or in glass at 4 degrees C. At room temperature in LDPE, a slight decrease in concentration due to adsorption was monitored. However the drug loss in PVC bags was greater. Dacarbazine and melphalan showed decreases in concentration, which were independent on the type of container material. The remaining analyzed agents showed no drug loss at all. In conclusion, investigated drugs were stable in all three container types, with the best stability in glass bottles, followed by LDPE and PVC.

Adsorption↗
PubMed1999

A new sensitive cardiac Troponin T rapid test (TROPT) for the detection of experimental acute myocardial damage in rats.

Cardiac Troponin T (cTnT) is a cardiac structural protein which is released in the circulation during myocardial cell damage. In this study we addressed the question of whether beta-sympathomimetic induced myocardial cell damage in rats can be detected in blood by the TROPT sensitive rapid test strip which is primarily manufactured for the detection of acute myocardial infarction in humans. Sixteen male rats and 16 female animals were treated once with orciprenalinesulphate s.c. to induce tachycardia. The control group which consisted of 16 rats of both sexes received vehicle (physiological saline). The heart rate of two groups of 10 rats (5 of each sex) was measured after orciprenaline or saline treatment. After 1-2 hours we could demonstrate an increased heart rate in the orciprenaline group. Furthermore in this group we could show elevated cTnT levels in peripheral blood measured with the enzyme-linked immunosorbent assay (ELISA) Enzymun-Test Troponin T for troponin T and a positive reaction of the TROPT sensitive test strip. When compared with the ELISA method, the test strip showed a positive reaction at cTnT levels of 0.64 ng/ml upwards. After 24 hours and 96 hours half of the animals were sacrificed for histological examination of the heart tissue. After 24 hours all orciprenaline treated and examined animals showed myofibrillar degeneration of the myocardial cells. The second half of the animals sacrificed 96 hours after treatment with the sympathomimetic drug showed reparative fibrosis of the myocardium. All animals with myocardial damage due to orciprenaline showed a positive test strip result 2 hours after injection. Twenty-four hours after injection only 8 of the 16 animals had a positive test strip result although histological cell damage was demonstrated. All animals treated with physiological saline had negative results of the test strip and showed no signs of myocardial cell damage. We conclude that the TROPT sensitive test strip is a rapid and reliable screening tool for detecting myocardial cell alteration in rats without the need of an expensive and time-consuming ELISA procedure if it is used in early phases of the experiment because all animals with myocardial damage were identified by the test 2 hours after induction of the damage. If the time range between the induction of the injury and the use of the test strip or the ELISA procedure is too wide, in our experiments 24 h, false negative results may occur.

Animals↗
PubMed1999

Germ tubes and proteinase activity contribute to virulence of Candida albicans in murine peritonitis.

Peritonitis with Candida albicans is an important complication of bowel perforation and continuous ambulatory peritoneal dialysis. To define potential virulence factors, we investigated 50 strains of C. albicans in a murine peritonitis model. There was considerable variation in their virulence in this model when virulence was measured as release of organ-specific enzymes into the plasma of infected mice. Alanine aminotransferase (ALT) and alpha-amylase (AM) were used as parameters for damage of the liver and pancreas, respectively. The activities of ALT and AM in the plasma correlated with invasion into the organs measured in histologic sections and the median germ tube length induced with serum in vitro. When the activity of proteinases was inhibited in vivo with pepstatin A, there was a significant reduction of ALT and AM activities. This indicates that proteinases contributed to virulence in this model. Using strains of C. albicans with disruption of secreted aspartyl proteinase gene SAP1, SAP2, SAP3, or SAP4 through SAP6 (collectively referred to as SAP4-6), we showed that only a Deltasap4-6 triple mutant induced a significantly reduced activity of ALT in comparison to the reference strain. In contrast to the Deltasap1, Deltasap2, and Deltasap3 mutants, the ALT induced by the Deltasap4-6 mutant could not be further reduced by pepstatin A treatment, which indicates that Sap4-6 may contribute to virulence in this model.

Alanine Transaminase↗
PubMed1999

Adhesion molecules in cerebrovascular diseases. Evidence for an inflammatory endothelial activation in cerebral large- and small-vessel disease.

BACKGROUND AND PURPOSE: Adhesion molecules mediate attachment and transendothelial migration of leukocytes as a critical step in pathogenesis of atherosclerosis. Their expression and release were comparatively investigated in patients with large- and small-vessel disease of the central nervous system. METHODS: With immunological methods, serum concentrations of endothelial-derived adhesion molecules (soluble endothelial-leukocyte adhesion molecule [sE-selectin], soluble vascular-leukocyte adhesion molecule-1, and soluble intercellular adhesion molecule-1 [sICAM-1]) were quantified in patients with obstructive disease of extracranial (n=89) and intracranial (n=20) large-vessel disease and patients with subcortical vascular encephalopathy (n=64), a cerebral small-vessel disease. As controls, age- and sex-matched subjects without obstructive cerebrovascular disease (n=67) were studied. RESULTS: We observed significantly increased serum concentrations of sE-selectin and sICAM-1 in patients with both obstructive disease of the large brain-supplying arteries and subcortical vascular encephalopathy. Interestingly, the highest levels were observed in intracranial macroangiopathy. Furthermore, concentrations of sICAM-1 and sE-selectin were significantly increased in current smokers but not in diabetic or hypertensive patients. CONCLUSIONS: The observation of elevated release of endothelial-derived adhesion molecules in both patients with stenoses of the large brain-supplying arteries and patients with subcortical vascular encephalopathy indicates that inflammatory endothelial activation and adhesion of leukocytes play similarly important roles in cerebral large- and small-vessel disease.

Aged↗
PubMed1999

Parameters for determination of Candida albicans virulence in murine peritonitis.

Using intraperitoneal (i.p.) infection of mice with Candida albicans we determined which parameters might be useful for characterization of virulence in this model. Upon i.p. infection of mice with two reference strains striking differences in lethality were detected. These differences in virulence corresponded with invasion of the liver and pancreas by the virulent strain and with a lack of invasion by the avirulent strain. The virulent strain was able to release high amounts of the enzymes alanine aminotransferase (ALT) and alpha-amylase (AM) from liver and pancreas into the blood plasma. Most likely, these enzymes were released by penetration of hyphae into the cytoplasm which was shown with electron microscopy. When invasion slowed down, there was also a drop in the activities of ALT and AM measured in the blood of infected mice. As both strains disseminated to the heart, kidneys, and lungs, dissemination into these organs was no reliable parameter for virulence in this model. However, only the virulent strain was able to reach the brain and to germinate in the kidneys and brain. In contrast to invasion and enzyme activities, the fungal load in the peritoneal cavity and in the neighbouring organs appeared not to be related with virulence. This may be concluded from the fact that there were no differences in the absolute colony forming units (cfu) and the length of persistence of both strains when similar inocula were used. We conclude that the ability of a given strain of C. albicans to invade neighbouring organs, to reach the brain upon dissemination and germination in the brain and kidneys may be used for measurement of virulence in this model when virulence is defined as lethality.

Alanine Transaminase↗
PubMed1998

Determination of airborne, volatile amines from polyurethane foams by sorption onto a high-capacity cation-exchange resin based on poly(succinic acid).

A high-capacity carboxylic acid-functionalized resin prepared by ring-opening metathesis polymerization based on cross-linked endo,endo-poly(norborn-2-ene-5,6-dicarboxylic acid) was used for the sampling of volatile, airborne amines from polyurethane (PU) foams. Six tertiary amines which represent commonly used promotors for the formation of PUs from diisocyanates and polyols, namely pentamethyldiethylenetriamine, diazabicyclooctane, N-methylmorpholine, N-ethylmorphine, 1,4-dimethylpiperazine and N,N-dimethylethanolamine, were sorbed onto the new resin. The sorption behavior of the new material was investigated in terms of loading capacities, the influence of concentration, flow-rate as well as of the amount of resin. Breakthrough curves were recorded from each single component as well as of mixtures thereof. Finally, the resin was used for the sampling of amines evaporating from PU foams applied in buildings. Further information about time dependent concentration profiles were obtained using a combination of GC-MS and Fourier transform IR spectroscopy.

Adsorption↗
PubMed1998

A vertical curriculum to teach the knowledge, skills, and attitudes of medical informatics.

It is becoming increasingly apparent that medical schools must begin teaching the knowledge, skills and attitudes of information literacy and applied medical informatics as core competencies in undergraduate medical education. The University of Vermont College of Medicine recognized that these core competencies were lacking in its curriculum, and in 1992 it implemented a four year, integrated program to give students the information habits essential to twenty-first century practice. The first graduates of the program are now in residencies and feedback has enabled the College to refine the program to better meet the informatics education needs of the next generation of physicians. The result of these efforts is the Vertical Curriculum in Information Literacy and Applied Medical Informatics; its process of development, the product of the process, and its outcomes are discussed.

Computer Literacy↗
PubMed1997

[Procalcitonin. A new marker for acute phase reaction in acute pancreatitis].

Procalcitonin is a protein which is found in elevated concentrations in the blood circulation during systemic bacterial, fungal or protozoal infection. In contrast to classical acute-phase proteins like C-reactive protein or interleukin-6, it is not elevated after operative trauma. In this paper we present current opinions on the assumed induction mechanisms of the protein by cytokines and endotoxin. Furthermore, the clinical value for early detection of systemic infections in abdominal and transplantation surgery is demonstrated by examples from the literature. Our investigation shows that eight patients with necrotizing pancreatitis had a PCT mean value of 6.9 ng/ml on the day of admission. Seven patients with edematous pancreatitis had only a PCT mean value of 0.69 ng/ml. Despite these differences in the mean values, a significant difference between the normal value and the mean value of the group with necrotizing pancreatitis or edematous pancreatitis was not observed due to the wide range of PCT levels in the group of patients with necrotizing pancreatitis. The fact that only a few of the patients had a superinfected necrosis with systemic evasion of bacterias or their toxins may be the reason for this wide range. We suggest that a discrimination between superinfected necrotizing or sterile pancreatitis and edematous pancreatitis by PCT could be possible but more extensive studies with microbiological examination of the necrotic material are required to recognize the subgroups and to establish the real diagnostic efficiency of PCT in clinical practice, especially in the prediction of the outcome of acute pancreatitis.

Acute-Phase Reaction↗
PubMed1997

Comparison of cardiac Troponin T and cardiac Troponin I concentrations in peripheral blood during orciprenaline induced tachycardia in rats.

In this study we addressed the question of whether the measurement of the cardiac structure protein cardiac Toponin I (cTnI) in serum is also able to detect marked myocardial cell damage in rats like cardiac Troponin T (cTnT). To answer this question 5 male rats and 5 female rats were injected with orciprenaline to induce myocardial cell damage. Further 5 animals of each sex received physiological saline as control. We could demonstrate that troponin I was rised significantly 6 hours after injection in serum as well as cTnT. 24 hours after injection cTnI was elevated on a lower significance level compared to cTnT. All values returned to normal 96 hours after the injection. We conclude that cTnI was also able to detect a marked myocardial cell damage in rats but we could show that cTnI was elevated on a lower significance level compared to cTnT. Furthermore we found that a cTnI increase to at least 4.1 ng/ml is necessary to detect marked myocardial cell injury in this rat tachycardia model.

Animals↗