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T Sauerbruch

Publications and source records attributed to T Sauerbruch.

At least 217 records · Page 12Linked to original sources
PubMed1997

The IL-1 system in HIV infection: peripheral concentrations of IL-1beta, IL-1 receptor antagonist and soluble IL-1 receptor type II.

The proinflammatory cytokine IL-1beta is thought to be involved in ongoing HIV disease. Furthermore, its naturally occurring inhibitors soluble IL-1 receptor type II (sIL-1RII) and IL-1 receptor antagonist (IL-1Ra) may play a pivotal role in regulating its biological action. To investigate the involvement of the IL-1 system we determined serum levels of IL-1beta, IL-1Ra and sIL-1RII in 90 HIV- patients. The obtained values were compared with markers of disease progression such as CD4+ count, 5'-neopterin. Beta2-microglobulin and soluble tumour necrosis factor receptors (sTNF-R) p55 and p75 and then compared with C-reactive protein (CRP), granulocyte count, IL-6 and TNF-alpha. While IL-1Ra concentrations increased significantly with progressive CDC disease stages, sIL-1RII and IL-1beta were not altered in our cohort. IL-1Ra showed statistical relation to decreasing CD4+ lymphocytes and increasing 5'-neopterin, beta2-microglobulin, sTNF-R p55, sTNF-R p75. Furthermore, IL-1Ra correlated positively with serum IL-6, TNF-alpha, CRP and granulocytes. In contrast, sIL-1RII and IL-1beta tended to show an inverse correlation or showed no significant relationship to all these parameters. IL-1beta was measurable only in a limited number of samples. IL-1Ra showed a clear relationship to acute inflammatory events as well as to the different disease stages. Our data suggest a dissociation between IL-1Ra and sIL-1RII serum levels which may indicate that the two IL-1 binding proteins have different pathophysiological roles in HIV infection.

Adult↗
PubMed1997

Physical laws of cholesterol gallstone fragmentation.

Efficient fragmentation is the most important prerequisite for successful treatment of gallstones by extracorporeally induced shock waves. No data are available on the amount of energy necessary for stone disintegration and on the threshold energy below which no further fragmentation occurs. We therefore performed an in vitro investigation on human cholesterol gallstones to elucidate physical laws governing shock-wave lithotripsy. First, the focal pressure of the lithotripter was measured to calculate the energy traversing a stone. Second, 96 gallstones from 16 gall bladders were analysed with respect to physicochemical composition, radiological features and ultrasound before fragmentation was performed. Energy for stone disintegration was constant within each stone family but varied between 4.6 mL-1 and 36.8J mL-1 in different families. This energy correlated linearly with stone volume. None of the radiological and physicochemical factors revealed a clear-cut correlation of the different energies necessary for similar stone disintegration. The threshold energy differed between 0.26 mJ and 1.04 mJ per pulse. In conclusion, stone volume was the best parameter predicting stone fragmentation. However, in cholesterol stones with a similar composition the required energy per volume varies considerably together with the threshold energy. Radiological and ultrasound parameters appear to be of minor importance in explaining these differences.

Acoustics↗
PubMed1997

Treatment of Barrett's esophagus by endoscopic argon plasma coagulation.

Barrett's esophagus is a premalignant condition characterized by the presence of specialized columnar epithelium in the distal esophagus. Conventional medical or surgical treatments do not consistently lead to a regression of Barrett's epithelium. However, restoration of squamous mucosa can occur in an anacid environment after endoscopic ablation of metaplastic epithelium. We report here on two patients with long-standing history of Barrett's esophagus who were treated with endoscopic argon plasma coagulation. By six months of endoscopic treatment, Barrett's epithelium had regressed by more than 50%, being replaced by apparently normal squamous epithelium in both patients. Extensive histological sampling confirmed the presence of squamous epithelium indistinguishable from normal esophageal mucosa. Both patients were asymptomatic under concomitant therapy with proton pump inhibitors with the exception of slight retrosternal discomfort the day after treatment. This demonstrates that endoscopic argon plasma coagulation may be considered for the treatment of Barrett's esophagus.

Adult↗
PubMed1997

Semiquantitative analysis of intrahepatic cytokine mRNAs in chronic hepatitis C.

In order to characterize intrahepatic cytokine production, the mRNA levels of interleukin (IL)-2, -4, and -10 and interferon (IFN)-gamma were semiquantitatively determined by reverse-transcription competitive polymerase chain reaction in liver specimens from patients with chronic hepatitis C (n = 23), chronic hepatitis B (n = 9), or primary biliary cirrhosis (n = 12) and normal liver (control) specimens (n = 12). IL-4 mRNA was undetectable. Similar IL-10 mRNA levels were detected in all samples studied, including the controls. Mean IFN-gamma and IL-2 mRNA levels were elevated in chronic inflammatory liver disease. IL-2 mRNA levels were similar in all 3 patient groups, but intrahepatic IFN-gamma mRNA levels were significantly higher in chronic hepatitis C than in chronic hepatitis B or primary biliary cirrhosis patients. This predominance of IFN-gamma may indicate a lower susceptibility of hepatitis C virus to the antiviral effects of this cytokine. The presence of IL-10 in normal liver may impair the induction of antiviral immune responses.

Actins↗
PubMed1997

Relationship between cytochrome P-450 induction by rifampicin, hepatic volume and portal blood flow in man.

OBJECTIVE: Induction of hepatic cytochrome P-450-dependent oxidative metabolism is related to an almost identical increase (30%) in both the liver weight and portal blood flow in animals. In humans by contrast, an increased liver blood flow (44%) but no significant increase in liver volume has been reported. DESIGN: Therefore, we studied prospectively the relationship between P-450 induction by rifampicin, hepatic volume and portal blood flow in 10 healthy volunteers. METHODS: After a pre-treatment phase (day 1 to 7) the 10 volunteers received 600 mg/day of rifampicin from day 7 to 12. The urinary 6-beta-hydroxycortisol output as a measure of oxidative metabolism (CYP3A4) and portal blood flow (pulsed Doppler ultrasound) were determined on days 1, 7, 11 and 13. Hepatic magnetic resonance volumetry was performed on days 1 and 13. RESULTS: Urinary 6-beta-hydroxycortisol output increased in all volunteers (P = 0.0051) from a median of 2.15 micrograms/day/kg (1.8-3.3 micrograms/day/kg) on day 1 to 9.9 micrograms/day/kg (5.7-14 micrograms/day/kg) on day 13. In 9 of 10 volunteers induction by rifampicin was related to an increase (P = 0.0218) in liver volume from a median of 1570 cm3 (1390-1830 cm3) to a median of 1690 cm3 (1420-1860 cm3). The portal flow as assessed by colour Doppler ultrasound did not change significantly between day 1 (median 22 cm/s (15-35 cm/s)) and day 13 (median 19 cm/s (16-39 cm/s)). CONCLUSION: A fourfold increase of urinary 6-beta-hydroxycortisol output after induction of cytochrome P-450 by rifampicin is associated with a significant but less than 10% increase in human liver volume. No increase of portal perfusion as assessed by Doppler ultrasound could be detected in this study.

Adult↗
PubMed1997

Hepatitis C virus-associated mixed cryoglobulinaemia.

Symptomatic mixed cryoglobulinaemia may dominate the course of hepatitis C virus infection. While conventional treatment of mixed cryoglobulinaemia relied on immunosuppression, the discovery of the close association to HCV infection has prompted treatment studies with interferon-alpha. Although symptomatic improvement is achieved in most patients during therapy, the rate of sustained response is low.

Cryoglobulinemia↗
PubMed1997

A citric acid solution is an optimal test drink in the 13C-urea breath test for the diagnosis of Helicobacter pylori infection.

BACKGROUND: The 13C-urea breath test (13C-UBT) is a simple, non-invasive and reliable test for the diagnosis of Helicobacter pylori infection. The duration of the test, the timing of breath sampling, and the accuracy of the method vary according to the test meal used. AIM: To identify the optimal test meal or drink for rapid and accurate performance of the 13C-UBT for the detection of H pylori infection. PATIENTS: Eighty patients with dyspeptic symptoms were included. Of these, 48 patients had a positive H pylori status and 32 a negative one according to the results of the rapid urease test, histological examination, and culture. METHODS: A 13C-UBT was performed after an overnight fast, on three consecutive days. On each study day a different test meal or drink was given (0.1 N citric acid solution, a standard semiliquid meal, or a semiliquid fatty meal) 10 minutes before giving 75 mg 13C-urea. Breath samples were collected at 0, 15, 30, 45, and 60 minutes, and analysed by isotype ratio mass spectrometry. Results were expressed as delta (delta) and considered as positive for H pylori if the highest delta (peak) was greater than 4.0. RESULTS: The delta peak obtained with the citric acid drink in H pylori positive subjects (24.1 (SEM 1.5)) was significantly higher than that obtained with any of the semiliquid meals (13.3 (SEM 1.1) and 17.1 (SEM 1.0) respectively, p < 0.001). Furthermore, this delta peak was obtained earlier with the citric acid drink (30 (SEM 2) minutes) than with the other two meals tests (53 (SEM 2) min and 45 (SEM 2) min, p < 0.001). The sensitivity of the 13C-UBT for the diagnosis of H pylori infection was 96-100% with all three test meals. This high sensitivity was, however, obtained from 15 minutes by giving citric acid as the test drink, from 45 minutes by giving a semiliquid fatty meal, and at 60 minutes by giving the semiliquid standard meal. The specificity was 100% for all test meals. Citric acid is inexpensive and palatable to patients. CONCLUSIONS: The 13C-UBT procedure with citric acid as the test drink is superior to the previously proposed semiliquid test meals in terms of 13CO2 recovery, time requirement, and cost. In routine clinical sampling, collection at times 0 and 30 minutes seems to be optimal and gives a high diagnostic accuracy.

Administration, Oral↗
PubMed1997

Variability of gallbladder emptying after oral stimulation.

BACKGROUND: To date, the intraindividual reproducibility of fasting and postprandial gallbladder (GB) volumes has not been established satisfactorily. Hence we examined the variability of postprandial GB motility, using the biplane Simpson method as a new sonographic tool for GB volume determination. METHODS: The biplane Simpson method was validated in vitro and in vivo and compared with the sum-of-cylinders method. Thereafter, postprandial GB emptying after a defined test meal was examined in 10 healthy volunteers over 108 min on days 1, 31, and 61. RESULTS: The results of the biplane Simpson method correlated with real volumes (r = 0.99) and provided a intra- and inter-observer variation of less than 5%. Intraindividually, differences in fasting GB volume ranged from 1.9 to 24.0 ml within the observation period. The patterns of GB emptying also showed fluctuations characterized by a rather large interindividual and intraindividual variability. CONCLUSIONS: The biplane Simpson method is a reliable tool for measuring GB volumes. The fasting and the postprandial GB volumes vary considerably within individuals when measured over a period of 2 months.

Adult↗
PubMed1997

[Determination of the count rate for quality control of combined lung ventilation and perfusion scintigraphy: case report].

We present the case of a 43-year-old male patient who suffered from a massive pulmonary embolism, induced by a peritoneovenous shunt of the Denver type. Calculation of the count rates of the ventilation and perfusion scintigraphy respectively showed a too low ventilation/perfusion ratio. After reinjection of additional 99mTc-MAA the second perfusion study showed further mismatch areals. Count rate ratio determination is essential as a clinical quality control.

Adult↗
PubMed1996

[Occurrence and significance of autoantibodies in the course of interferon therapy of chronic hepatitis C].

BASIC PROBLEM AND OBJECTIVE: Autoimmunity may occur in chronic hepatitis C (CHC) as a primary event or may be induced by interferon-alpha (IFN-alpha). The existence of autoantibodies (AAB) is considered to be a contraindication to interferon treatment. It was the aim of this study to determine the extent to which signs of autoimmune disease occur in the treatment of CHC with interferon, even in patients with existing antibodies. PATIENTS AND METHODS: In 1994 a pre-defined AAB spectrum and thyroid function parameters were determined every other month in 41 patients with CHC (16 women, 25 men; median age 42 years) before and after they had been treated with IFN-alpha, even when AABs were already present. RESULTS: AABs were demonstrated in 17 patients (41%) before and in 26 (63%) during interferon treatment (P = 0.001). In 13 patients new AABs were demonstrated, while previously present AABs were no longer found in four patients. AABs against thyroglobulin (TGA) increased significantly, during interferon treatment (P = 0.001). All except thyroid AABs were demonstrable only at times and in low titres. None of the patients had an auto-immune disease before treatment. But autoimmune thyroiditis developed in four of 19 patients with thyroid AABs. These patients also had constant TGAs in high titres, and antibodies against microsomes were additionally demonstrated in two. No other autoimmune disease occurred during or after interferon treatment. CONCLUSION: Interferon frequently induces the formation of AABs. The demonstration of AABs before or during interferon treatment is no contraindication to it, with the exception of preexisting thyroid antibodies, which indicate a high risk of autoimmune thyroiditis.

Adult↗
PubMed1996

A comparative study of different enzyme immunosorbent assays for human tumor necrosis factor-alpha.

Enzyme immunosorbent assays (ELISA) for human tumor necrosis factor-alpha (TNF-alpha) are available from many companies. Although this cytokine is meanwhile well established in scientific work its detection in human blood still leads often to conflicting results. We studied the analytical performance of three different commercial ELISA (Amersham, Immunotech and Medgenix Diagnostics) in plasma samples of 30 human immunodeficiency virus (HIV) infected individuals. All kits showed significantly different mean concentrations of TNF-alpha in the study population (p < 0.05). Kit A: 30.9 pg/ml +/- 46.6 vs. kit B: 46.9 pg/ml +/- 24.8 vs kit C: 11.8 pg/ml +/- 11.6. Results of assays A and B (r = 0.34) as well as A and C (r = 0.31) were not significantly correlated. A good statistical relation between values was only found for assay B and assay C (r = 0.80. p < 0.001). Three plasma samples were spiked with TNF-alpha standard of the corresponding kit to a final concentration of 200 pg/ml. The detection results of these samples were compared with the variation conceded by the manufacturer. Assay A detected two samples above the corresponding coefficient of intra-assay variation (recovery: 81.8% and 89.2%). All three values obtained with assay B were markedly out of its variation range (recovery: 88.7%, 84.6% and 89.0%) while assay C showed again two results above the intra-assay variation (recovery: 92.1% and 89.6%). In our observations we found relevant differences between commercial ELISA kits of different manufacturers, which made interpretation of TNF-alpha in human plasma samples difficult. Additionally, it should be taken into consideration that plasma specimen may contain cytokine-binding proteins or autoantibodies which are capable of blocking epitopes of TNF-alpha. This may lead to the loss of the necessary immunoreactivity which prevents detection antibodies from recognizing these molecules.

Enzyme-Linked Immunosorbent Assay↗