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G Steinbach

Publications and source records attributed to G Steinbach.

At least 55 records · Page 3Linked to original sources
PubMed1998

Prognostic significance of soluble interleukin-2 receptor-alpha in adenocarcinoma of the pancreas.

Soluble interleukin-2-receptor-alpha (sIL-2Ralpha) serum concentrations were examined in chronic pancreatitis patients, patients with cystadenocarcinoma of the pancreas, patients with adenocarcinoma of the pancreas and healthy blood donors. sIL-2Ralpha serum concentrations in pancreatic cancer patients were significantly higher than those of normal control subjects or chronic pancreatitis patients. In patients with adenocarcinoma of the pancreas no significant differences were found between sIL-2Ralpha and tumor size, grading, resectability and lymph node involvement. In Kaplan-Meier regression analysis patients with adenocarcinoma of the pancreas with low sIL-2Ralpha levels (<500 U/ml) lived significantly shorter than patients with sIL-2Ralpha concentrations above 500 U/ml (P < 0.01), suggesting that determination of sIL-2Ralpha serum concentrations could provide additional important information about prognosis.

Adenocarcinoma↗
PubMed1998

Ibuprofen does not impair renal function in patients undergoing infrarenal aortic surgery with epidural anaesthesia.

OBJECTIVE: To investigate the effect of preoperative ibuprofen administration on renal function during and after infrarenal aortic surgery under thoracolumbar epidural anaesthesia (EPA). DESIGN: A prospective randomised, double-blinded clinical study. SETTING: Operation room and intensive care unit in a university hospital. PATIENTS: Twenty-six consecutive patients scheduled for elective infrarenal aortic surgery. INTERVENTIONS: The patients were prospectively randomised to receive 400 mg ibuprofen intravenously (i.v.) or a placebo aliquot before surgery. MEASUREMENTS AND RESULTS: We assessed renal function by calculating creatinine clearance, and fractional sodium excretion before surgery (baseline), 1 h after cross-clamping (intraoperative), 6 h after cross-clamping (postoperative) and 24 h after cross-clamping (on the 1 st postoperative day). At each point in time, we additionally registered haemodynamics and determined the plasma concentration of 6-keto-PGF1alpha (stable metabolite of prostacyclin, PGI2), bicyclic PGE2 (stable metabolite of PGE1 E2), active renin, aldosterone and vasopressin by radioimmunoassays. Throughout the observation period the renal function parameters mostly remained within the normal range without a significant difference between ibuprofen- and placebo-treated patients (creatinine clearance: baseline 41 +/- 3 vs 38 +/- 6, intraoperative 57 +/- 8 vs 64 +/- 11, postoperative 64 +/- 9 vs 56 +/- 9, first postoperative day 43 +/- 5 vs 47 +/- 6 ml x min x m(-2), means +/- SEM). The plasma levels of 6-keto-PGF1alpha (68 +/- 8 vs 380 +/- 71* ng x l(-1)), bicyclic PGE2 (57 +/- 5 vs 88 +/- 9* ng x l(-1)) and vasopressin (14 +/- 7 vs 45 +/- 10* ng x l(-1), p < 0.0125), however, were significantly higher during the intraoperative period in the placebo-treated patients. CONCLUSION: The inhibition of endogenous prostaglandin release by ibuprofen does not substantially impair renal function during infrarenal aortic surgery under EPA.

Aged↗
PubMed1998

Microflora of gastric biopsies from patients with duodenal ulcer and gastric cancer: a comparative study of patients from Korea, Colombia, and the United States.

It remains unclear why the spectrum of H. pylori-related diseases differs among different geographic regions. We examined the non-H. pylori contamination rates of the stomach in patients with duodenal ulcer or gastric adenocarcinoma from three different regions with different spectra of H. pylori-related diseases. Gastric biopsies were cultured from patients with duodenal ulcer or histologically proven gastric cancer from Seoul, Korea; Bogota, Colombia; and Houston, Texas. The frequency of non-H. pylori contamination was tallied in relation to the clinical diagnosis. Cultures from 247 duodenal ulcer patients and 165 patients with gastric cancer had bacterial growth. H. pylori was isolated from 207 (73.7%) patients with duodenal ulcer and 90 (47.1%) patients with gastric cancer (P < 0.001). In patients with duodenal ulcer (DU) or gastric cancer (GC), the rate of positive cultures for H. pylori were not statistically different (P > 0.143 for DU, P > 0.190 for GC) between regions. The frequency of isolation ranged from 69% to 79% for DU patients and from 39% to 50% for gastric cancer patients. Non-H. pylori bacterial contamination was found more frequently (63%) in Colombian duodenal ulcer patients compared to 30% ulcer patients from the United States or Korea (P < 0.001). Non-H. pylori growth occurred in 50.8-75.5% of cancer patients and was significantly lower in US patients than in patients from either Colombia or Korea (P < 0.01). The geographic location as well as disease status affects the rate of H. pylori recovery and non-H. pylori contamination of the stomach and may play a role in the geographic differences in manifestation of H. pylori infection. The fact that the proportion of gastric cancer patients in the United States with non-H. pylori contamination was significantly less than that of Korea or Colombia shows that the notion of an almost universal increase in gastric microbial content in gastric adenocarcinoma should be reconsidered.

Adenocarcinoma↗
PubMed1998

Specificity of cardiac troponins I and T in renal disease.

UNLABELLED: We investigated and compared serum levels of cardiac troponins I(cTnl) and cardiac troponin T (cTnT) in 85 renal patients (chronic renal impairment n = 23, continuous ambulatory peritoneal dialysis n = 20, hemodialysis n = 42). Patients with the following conditions were excluded: myocardial infarction, angina pectoris, liver disease, malignant neoplasms, enforced physical activity, skeletal muscle trauma, myositis, rhabdomyolysis and seizures. Troponin T was measured by the second generation cTnT-ELISA with a cut-off value = 0.1 microgram/l. Troponin I was measured by a cTnI immunoassay analyser with a cut-off value = 2.0 micrograms/l. Additionally, creatine kinase (CK), CK-MB activity, CK-MB mass concentration and myoglobin levels were measured. Specificity was determined as the fraction of true-negative cases compared to the total number of false-positive and true-negative cases. Specificity for cTnT was 96% [78-100] in patients with renal impairment (creatinine > 150 mumol/l), 95% [75-100] in continuous ambulatory peritoneal dialysis patients, but in hemodialysis patients it was 75% [53-92] for short-term hemodialysis (< 1 year) and 46% [24-68] for long-term hemodialysis (> 1 year). There was a weak correlation between cTnT levels and duration of hemodialysis therapy (r = 0.35, n = 34, p < 0.04). Specificity for cTnI in renal impairment patients was 96% [78-100] and 100% [84-100] in continuous ambulatory peritoneal dialysis and all hemodialysis patients. None of the studied markers showed higher specificity than cTnI. Only myoglobin was less specific than cTnT in hemodialysis patients. Different clearances of the troponins during dialysis (investigated by pre-hemodialysis and post-hemodialysis levels) cannot explain the discordant results of cTnT and cTnI. CONCLUSION: Cardiac troponin I exhibits higher specificity than cardiac troponin T in hemodialysis patients. Uremic myopathy could explain falsely elevated troponin T levels in hemodialysis patients.

Adult↗
PubMed1997

Signal-averaged electrocardiogram in patients with insulin-dependent (type 1) diabetes mellitus with and without diabetic neuropathy.

The purpose of this study was to investigate the presence of ventricular late potentials derived from signal-averaged ECG in patients with IDDM with and without diabetic neuropathy. Eighty patients with IDDM but without evidence of cardiac disease and 80 age-matched healthy control subjects were investigated. The corrected QT interval was measured from the standard surface electrocardiogram. Ventricular late potentials were derived from signal-averaged electrocardiogram. Out of the 80 diabetic patients, 20 had an autonomic neuropathy, 20 had an isolated peripheral neuropathy, and 40 had no symptoms of neuropathy. The corrected QT interval was significantly prolonged in patients with an autonomic neuropathy as compared with the control group (436 +/- 23 ms(x 5) vs 384 +/- 23 ms(x 5), p < 0.001). In the other patient groups there was no significant prolongation of the corrected QT interval. Ventricular late potentials were present in 3 diabetic patients with an isolated peripheral neuropathy and in 1 control subject (NS). No diabetic patient with an autonomic neuropathy had ventricular late potentials. Our data did not indicate an increased incidence of ventricular late potentials derived from signal-averaged electrocardiogram in diabetic patients independent of a coexisting diabetic neuropathy or a prolonged corrected QT interval.

Adolescent↗
PubMed1997

Importance of the serovar-specific plasmid for virulence of salmonella strains in calves.

To evaluate the influence of serovar-specific plasmids on salmonella virulence in calves, experiments were performed involving infection, by the oral route, with mixtures of strains containing equal counts of a plasmid-carrying and a plasmid-free strain of the same serovar. The concentration ratio between the plasmid-carrying and the plasmid-free strain which had developed in the organs of the infected animals was used for a comparative evaluation of virulence and pathogenetic behaviour of the strains. While in the S. typhimurium strains studied, the presence of the plasmid was accompanied by a significantly increased colonization and multiplication of the agent in the host's body, examination of S. enteritidis and S. dublin revealed that the plasmid-free strains exhibited identical or even significantly higher bacterial counts than the plasmid-carrying strains in organs. The fact that plasmid-free salmonella strains with a high virulence for calves have been found demonstrates that the presence of a serovar-specific plasmid is not an indispensable requirement for the development of salmonellosis in calves.

Animals↗
PubMed1997

The potential role of procalcitonin and interleukin 8 in the prediction of infected necrosis in acute pancreatitis.

BACKGROUND: Infection of pancreatic necrosis has a major impact on clinical course, management, and outcome in acute pancreatitis. Currently, guided fine needle aspiration is the only means for an early and accurate diagnosis of infected necrosis. Procalcitonin (PCT), a 116 amino acid propeptide of calcitonin, and interleukin 8 (IL-8), a strong neutrophil activating cytokine, are markers of severe inflammation and sepsis. AIMS: To analyse the clinical value of PCT and IL-8 as biochemical parameters for predicting infected necrosis in acute pancreatitis. PATIENTS AND METHODS: Fifty patients with acute pancreatitis entered this prospective study and were stratified into three groups according to morphological and bacteriological findings: 18 patients with oedematous pancreatitis (group I), 14 patients with sterile necrosis (group II), and 18 patients who developed infected necrosis a median of 13.5 days after the onset of symptoms (group III). After admission serum samples were drawn daily for two weeks. Concentrations of PCT and IL-8 were measured by chemoluminescent immunoassays (upper reference range 0.5 ng/ml for PCT and 70 pg/ml for IL-8). The routine parameter C-reactive protein was determined by laser nephelometry (upper reference range 10 mg/l). RESULTS: Median concentrations of PCT and IL-8 were significantly higher in patients with infected necrosis than in those with sterile necrosis during the observation period, whereas there was no difference in C-reactive protein. In oedematous pancreatitis overall median concentrations of all three parameters were low. By receiver operating characteristics best cut off levels for predicting infected necrosis or persisting pancreatic sepsis were 1.8 ng/ml for PCT and 112 pg/ml for IL-8. If these cut off levels were reached on at least two days, sensitivity, specificity, and accuracy for the prediction of infected necrosis were 94%, 91%, and 92% for PCT and 72%, 75%, and 74% for IL-8, respectively. After surgical treatment of infected necrosis median PCT and IL-8 values continued to be significantly higher in patients with persisting pancreatic sepsis (n = 11) compared with those having an uneventful postoperative course (n = 7). For the preoperative differentiation between infected necrosis and sterile necrosis guided fine needle aspiration was performed in 24 patients with necrotising pancreatitis and reached a diagnostic accuracy of 84% compared with 87% for PCT, and 68% for IL-8. There was no correlation between the aetiology of acute pancreatitis or the extent of necrosis and PCT or IL-8. CONCLUSION: PCT and IL-8 are found in high concentrations in infected necrosis and associated systemic complications in patients with acute pancreatitis. The course of PCT shows the closest correlation with the presence of infected necrosis. Monitoring of serum PCT is a potential new marker for the non-invasive and accurate prediction of infected necrosis as well as for the selection of patients with persisting septic complications after surgical debridement.

Adolescent↗
PubMed1997

[Long-chain fatty acids of Pasteurella multocida nad Pasteurella haemolytica].

The relative contents of long-chain fatty acids in P. multocida and P. haemolytica were investigated. A dependence on the composition of the broth was established. Accordingly, comparative quantitative studies on fatty acid contents have to be conducted using bacteria grown with the same lot of broth medium. As for P. multocida, there were significant differences between the serovars (C14 in TDHM and C16, delta 2C18 in BPL). These differences are, however, not significant to replace serotyping. Highly significant differences were also detected between P. multocida isolates from nasal swabs and pneumonic lungs (interims of C14, delta C16 on BPL and BRU). The largest differences were measured for strains grown on BRU, which is interpreted as an expression of virulence. Significant differences were found between biotypes A and T of P. haemolytica, namely for C14, C16 in TDHM, and C14, delta C16, C16, C18 in BPL medium.

Animals↗
PubMed1997

[Efficacy of maternal Salmonella antibodies and experimental oral infection of chicks with Salmonella enteritidis].

Distribution of maternally transmitted Salmonella antibodies and their protective effects were studied in the progeny of broiler breeder birds which had been vaccinated with live S. Typhimurium and inactivated S. Enteritidis vaccines. Vaccination resulted in a significant increase of the antibody concentration in yolk of hatching eggs and in serum and jejunum of the progeny of immunized breeder birds. Higher antibody titres for isotypes IgG and IgA were still seen on day 21 of age. Antibody production of isotypes IgA and IgM by the chickens themselves was found between 14 and 21 days of age. Two challenge models (10(2) cfu/bird on day 1 of age and a seeder bird model, respectively) were used to evaluate the efficacy of maternal antibodies against challenge with S. Enteritidis. Using both models numbers of challenge organisms were lower in the caeca of the progeny of immunized parent birds between day 7 and day 21 of age (maximum about 1.5 log10 units) compared with control chicks. The results indicate the efficacy of maternally transferred antibodies but it remains the question of their practical relevance. The effects of acquired maternal antibodies on an active immunization of the progeny of immunized breeder birds with live Salmonella vaccines are discussed.

Animals↗
PubMed1997

S phase determination in intact colonic crypts by histone H3 messenger RNA in situ hybridization and confocal microscopy.

Proliferating cells have a restricted three-dimensional spatial distribution within the crypt, which is the proliferative unit of the colon. Accurate quantitative and spatial analyses of S phase cells in the colon have therefore been limited by histological techniques. To overcome these limitations, S phase cells in microdissected intact colonic crypts of control, modified-starved, and refed rats were labeled by histone H3 in situ hybridization and analyzed by confocal microscopy. High-resolution digital images of the crypt cell nuclei stained with cyanine nucleic acid and of the labeled S phase cells were produced from confocal microscopic optical crypt sections. The S phase labeling index (LI) per whole crypt significantly (P < 0.001) discriminated the proliferative differences between control, modified-starved, and refed rats and correlated (r = 0.92) with the LI determined from histological crypt sections of the same rats. The variance component of the LI attributable to differences between whole crypts, 0.44 (95% confidence interval, 0.38-0.51), was considerably smaller than that attributable to differences between histological crypt sections, 6.07 (95% confidence interval, 5.18-6.96). Confocal microscopy and histone H3 in situ hybridization of intact three-dimensional crypts enables precise in vitro quantitation and spatial analysis of the total and S phase crypt cells.

Animals↗
PubMed1996

Histone H3 messenger RNA in situ hybridization correlates with in vivo bromodeoxyuridine labeling of S-phase cells in rat colonic epithelium.

Measurements of cell cycle phase fractions, particularly S-phase, are useful for studies of cell biology and carcinogenesis. Up-regulation of histone gene expression is tightly coupled to the G1-S-phase transition of the cell cycle, and mRNA levels rise 30-100-fold during S-phase. Labeling of histone H3 mRNA using in situ hybridization (ISH) was assessed as a measure of S-phase cells and compared with that found using in vivo 5-bromodeoxyuridine (BrdUrd) labeling in formalin-fixed rat colonic crypts under baseline, modified 72-h starvation, and 24-h refeeding conditions. The labeling index scored in single-labeled sections by histone H3 ISH tightly correlated with that found by in vivo BrdUrd labeling (r = 0.99, p < 0.0001) and clearly discriminated between the control, starved, and refed states (P < 0.001). In 180 crypt sections double labeled using histone H3 ISH and BrdUrd, 92% of 1572 labeled cells exhibited both nuclear BrdUrd and cytoplasmic histone H3 label. It is concluded that histone H3 ISH is an accurate measure of the S-phase fraction and provides an alternative to in vivo BrdUrd labeling in rat colon. This finding warrants validation in human studies.

Animals↗
PubMed1996

Na-K/2Cl transporter inhibition for reduction of postischemic kidney failure tested in autologous reperfusion.

Postischemic kidney function may be influenced by donor conditioning. The sulfamoyl-benzoate "piretanide" (P) is a diuretic agent with an inhibitory effect on the luminal Na-K-2CL-transporter system in the ascending part of the loop of Henle. A clinical pilot study demonstrated a lower rate of organ dysfunction following transplantation in humans when the donor organs were pretreated with piretanide. In an experimental ex vivo model the effect of piretanide on immediate organ function following long or short cold ischemia was studied. Porcine kidneys (n = 36) were removed after in situ transaortal hypothermic flushing with 21 Eurocollins solution. Following short storage (1 h, n = 18) or long storage (24 h, n = 18) the kidneys were reperfused with intraoperatively drawn heparinized autologous blood diluted with Ringer's lactate to a hematocrit of 25%. Urine flow was higher in the piretanide-pretreated group (p), especially after long storage. The electrolyte loss was comparable in both groups. Postischemic endogenous creatinine clearance was significantly elevated in the treatment group (4.45 +/- 0.6 ml/min per 100 mg in P vs 1.91 +/- 0.4 ml/min per 100 mg, in control, P < 0.05 Mann-Whitney test). Renal hemodynamics were improved by piretanide, resulting in significantly lower resistance and allowing higher flow during pressure-controlled perfusion. O2 consumption, representing general metabolic activity, was higher after long storage, indicating an earlier recovery from cold ischemia. In this ex vivo model, autologous reperfusion of porcine kidneys could be improved by piretanide pretreatment. Autoregulation of kidney vasculature was maintained as well as functional parameters such as creatinine clearance or gluconeogenesis. Therefore, piretanide may be used in larger clinical trials to further improve organ quality in times of donor shortage.

Animals↗
PubMed1996

Influence of prior infection on the dynamics of bacterial counts in calves experimentally infected with Salmonella dublin.

The aim of this investigation was to obtain information on the influence of immunity gained from a previous infection in calves on the dynamics of a subsequent salmonella infection. Immune and non-immune animals were orally infected with virulent S. dublin. After infection clinical symptoms and the development of bacterial counts in intestinal contents and intestinal mucosa, as well as in intestinal lymph nodes, spleen and liver were compared. The protection of the immune animals became evident as milder courses of infection and in lower bacterial counts in all examined organs. The greatest absolute and relative difference between the counts of immune animals and controls was in the intestinal mucosa. While absolute counts were lower, the proportion of bacteria was higher in the lymph nodes of immune animals. This apparently more intensive penetration in immune animals was feigned by a general and immunity independent negative correlation between concentration of salmonella in the mucosa and of salmonella found in the intestinal lymph nodes. This time course of counts provided evidence that enhanced defence of immune calves was particularly pronounced 3 and 4 days after the onset of infection.

Animals↗
PubMed1996

Cell kinetic analysis of intact rat colonic crypts by confocal microscopy and immunofluorescence.

BACKGROUND & AIMS: Precise quantitative and spatial analysis of cell cycle-related biomarkers in colonic crypts is often vital for studies of colon carcinogenesis and cancer prevention. To overcome the limitations of histology, confocal laser microscopy of microdissected whole crypts was used to quantitate S phase and mitotic cells. METHODS: Microdissected distal colonic crypts were studied in a modified rat starvation refeeding model. S phase cells were labeled in vivo with 5-bromodeoxyuridine. Mitotic cells were labeled with MPM2 (antibody to mitosis-specific epitope) and also assessed for chromatin morphology with propidium iodide. Sequential optical crypt sections, produced by confocal microscopy, were digitally imaged. S phase labeling indices per whole crypt were also compared with those derived by conventional immunohistochemistry. RESULTS: S phase and mitotic cells were clearly discriminated without background staining. The labeled S phase cell number and fraction per whole crypt were significantly decreased with starvation and increased with refeeding. Variability in the labeling index between whole crypts analyzed by confocal microscopy was significantly smaller than between histological crypt sections. Consequently, the intervention contributed to 92.2% of the total variability of the labeling index in whole crypts but only to 59% of the variability in histological sections. CONCLUSIONS: Major limitations of histology are overcome by crypt microdissection and confocal microscopic analysis. The total crypt cell population as well as labeled M phase and S phase cells can be imaged, localized, and quantitated with improved precision.

Animals↗
PubMed1996

Participants' perceptions of a phase I colon cancer chemoprevention trial.

To assess participants' perceptions of a phase I colon cancer chemoprevention trial using a calcium intervention, questionnaires were mailed to trial participants at the conclusion of the study. Responses to questionnaire items reported here include (1) perceived benefits and barriers of participation, (2) interest in participating in future trials, (3) willingness to pay trial expenses out of pocket, and (4) posttrial continuation of the calcium regimen. The study found that the most highly rated trial benefit was the perception of potential colon cancer prevention; the trial barrier reported to be the most troublesome was inappropriate or mistaken billing for study visits. Three fourths of the subjects expressed an interest in future trials of the same duration. For trials of longer duration, this percentage decreased to 66%. Approximately half did not object to participation in future trials involving placebos, and just over one third indicated that they would either definitely (8%) or probably (27%) have joined the calcium trial even if they had to pay some study expenses out of pocket. Over 90% indicated they would continue taking the calcium pills if calcium is shown to be effective. The level of perceived benefits was positively associated with reported interest in participating in future trials of the same and longer durations, and the level of reported difficulty with trial pills and procedures was inversely related to interest in future placebo-controlled trials. The results of this study, in conjunction with results of prospective studies of trial participation, may be applied in future chemoprevention trials to facilitate recruitment, reduce attrition, and promote positive trial experiences for participants by emphasizing frequently reported benefits and minimizing frequently reported barriers.

Adenocarcinoma↗
PubMed1996

World Health Organisation--supervised interlaboratory comparison of ELISAs for the serological detection of Salmonella enterica serotype Enteritidis in chickens.

A collaborative exercise, supervised by the World Health Organisation, was set up to compare ELISAs used for the serological detection of Salmonella enteritica serotype Enteritidis in chickens. The aim was to ascertain how far agreement could be reached on the interpretation of optical density readings for high titre, intermediate titre and low titre sera. Two sets of sera were sent to 14 participants. The first set compared high, medium and low titre sera raised in specified-pathogen-free and commercial broiler breeder chickens. The second set comprised 20 sera of different antibody titres raised in commercial birds reared under laboratory conditions and sent blind. Both indirect and double-antibody sandwich blocking ELISAs were used with a number of different detecting antigens. With a few exceptions good agreement was reached on the interpretation of results obtained from high and low titre sera from the optical density obtained with a single serum dilution. Differences were observed in the interpretation of medium titre sera. The results suggested that most ELISAs produce reasonably comparable results and that practical problems may arise from interpretation of the results mainly as a result of the choice of the criteria used for differentiating sera obtained from infected and uninfected chickens. These problems are discussed.

Animals↗