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C Stumpf

Publications and source records attributed to C Stumpf.

At least 19 recordsLinked to original sources
PubMed2006

A multi-analytical platform approach to the metabonomic analysis of plasma from normal and Zucker (fa/fa) obese rats.

Plasma obtained from 20 week old normal Wistar-derived and Zucker (fa/fa) rats was analysed using a number of different analytical methodologies to obtain global metabolite profiles as part of metabonomic investigations of animal models of diabetes. Samples were analysed without sample pre-treatment using 1H NMR spectroscopy, after acetonitrile solvent protein precipitation by ultra-performance liquid chromatography-MS (UPLC-MS) and after acetonitrile protein precipitation and derivatisation for capillary gas chromatography-MS (GC-MS). Subsequent data analysis using principal components analysis revealed that all three analytical platforms readily detected differences between the plasma metabolite profiles of the two strains of rat. There was only limited overlap between the metabolites detected by the different methodologies and the combination of all three methods of metabolite profiling therefore provided a much more comprehensive profile than would have been provided by their use individually.

Animals↗
PubMed2006

Increased prolactin in acute coronary syndromes as putative Co-activator of ADP-stimulated P-selectin expression.

Prolactin and leptin are newly recognized platelet co-stimulators due to enhancement of ADP-induced platelet aggregation. The aim of our study was to assess whether both hormones prolactin and leptin play a role as co-activators of platelet activation in patients with acute coronary syndromes. Twenty-one patients with acute coronary syndromes, 10 with stable angina pectoris and 10 controls were studied. Patients with acute coronary syndromes showed significantly higher prolactin and leptin values and a significant increased P-selectin expression on platelets compared to patients with stable angina pectoris or controls. However, patients with acute myocardial infarction as a subgroup of acute coronary syndromes showed the highest prolactin levels as well as ADP stimulated P-selectin expression. In the myocardial infarction subgroup prolactin values showed a significant correlation to ADP stimulated P-selectin expression on platelets (r (2)=0.41; p=0.025), whereas leptin was not correlated. Our data indicate an association between increased prolactin values and enhanced P-selectin expression on platelets in patients with acute coronary syndromes. Therefore, the stress hormone prolactin could be a co-stimulator of platelet activation in these patients. In contrast, the putative platelet activator leptin does not seem to play a major role in acute coronary syndromes.

Adenosine Diphosphate↗
PubMed2004

Delay of neutrophil apoptosis in acute coronary syndromes.

Apoptosis of polymorphonuclear neutrophils (PMN) is currently discussed as a key event in the control of inflammation. This study determined PMN apoptosis and its underlying mechanisms in controls (C), patients with stable (SAP) or unstable angina (UAP), and with acute myocardial infarction (AMI). Blood was drawn from 15 subjects of each C, SAP, UAP, and AMI. Apoptosis was measured by flow cytometry in isolated PMN (propidium iodide staining) and PMN from whole blood (CD16, FcgammaRIII). Serum cytokines were determined by enzyme-linked immunosorbent assay. Apoptosis of isolated PMN was delayed significantly in acute coronary syndromes (ACS) as compared with SAP or C (C, 51.2+/-12.6%; SAP, 44.9+/-13.6%; UAP, 28.4+/-10.1%; AMI, 20.3+/-8.5%; AMI or UAP vs. SAP or C, P<0.001). These results were confirmed by measurement of PMN apoptosis in cultured whole blood from patients and controls. Moreover, serum of patients with ACS markedly reduced apoptosis of PMN from healthy donors. Analysis of patients' sera revealed significantly elevated concentrations of tumor necrosis factor alpha, interferon-gamma (IFN-gamma), granulocyte macrophage-colony stimulating factor (GM-CSF), and interleukin (IL)-1beta in ACS (vs. C and SAP). IFN-gamma, GM-CSF, and IL-1beta significantly delayed PMN apoptosis in vitro. Furthermore, coincubation of PMN with adenosine 5'-diphosphate-activated platelets significantly inhibited PMN apoptosis as compared with coculture with unstimulated platelets. This study demonstrates a pronounced delay of PMN apoptosis in UAP and AMI, which may result from increased serum levels of IFN-gamma, GM-CSF, and IL-1beta and from enhanced platelet activation. Therapeutical modulation of these determinants of PMN lifespan may provide a new concept for the control of inflammation in ACS.

Acute Disease↗
PubMed2003

Upregulation of CD40-CD40 ligand (CD154) in patients with acute cerebral ischemia.

BACKGROUND AND PURPOSE: Inflammation and hypercoagulability contribute to the development of acute cerebral ischemia. Both can be mediated by the CD40 system. This study investigated whether the CD40 system and related mediators are upregulated in patients with transient ischemic attack (TIA) or stroke. METHODS: Seventeen patients with TIA, 60 patients with complete stroke, and 15 control subjects were investigated. CD154 and P-selectin were analyzed on platelets and CD40 on monocytes during and 3 months after acute cerebral ischemia by double-label flow cytometry. Blood concentrations of soluble CD154 and monocyte chemoattractant protein-1 (MCP-1) were evaluated. RESULTS: Our main findings are as follows: (1) patients with acute cerebral ischemia showed a significant increase of CD154 on platelets and CD40 on monocytes compared with controls; (2) plasma levels of soluble CD154 were significantly higher in these patients; (3) these patients had significantly higher numbers of prothrombotic platelet-monocyte aggregates; (4) the chemoattractant MCP-1 was significantly elevated in cerebral ischemia; and (5) at 3 months' follow-up, upregulation of CD154 still persisted in patients with previous acute cerebral ischemia. CONCLUSIONS: Patients with acute cerebral ischemia show upregulation of the CD40 system, which might contribute to the known proinflammatory, proatherogenic, and prothrombotic milieu found in these patients.

Acute Disease↗
PubMed2003

[Retrospective study of malignant melanoma patients treated with mistletoe extracts].

OBJECTIVE: The aim of the present investigation was to analyze survival time and survival rate of all patients with malignant melanoma who had been counseled at the Tumorambulanz Herdecke of the Community Hospital Herdecke. PATIENTS AND METHODS: 284 melanoma patients were included in a retrospective questionnaire study. Only those patients were considered for analysis in whom the prognostic factors histology, tumor localization, and Clark level were known. The data of the study population were compared with patient data obtained from the literature. RESULTS: 94 patients were included in the analysis. 66 of whom had received and 7 had not received mistletoe treatment, in the remaining 21 patients there was no information whether or not mistletoe treatment had been given. Thus, we did our study without a clearly defined internal control group. The median survival time among patients treated with mistletoe had been 14.1 years. The 5- and 10-year survival rates were 80 and 68% for the mistletoe-treated patients, respectively. DISCUSSION: The 5-year survival rate of the mistletoe-treated patients is comparable to that of patients without mistletoe therapy while the 10-year survival rate is a little bit lower. This may be due to the fact that, in contrast to the patients from the relevant literature, 33.3% of the patients suffered from lymph node and/or distant metastases already before counseling the Tumorambulanz Herdecke. Moreover, 50% of our patients had melanoma of Clark level IV in contrast to 22.2% or 31% in the relevant literature. CONCLUSIONS: In spite of the theoretical reservations against mistletoe treatment in melanoma patients, our retrospective analysis did not show any clues about disadvantages of mistletoe treatment in melanoma patients. A controlled prospective study therefore should prove the efficacy of a mistletoe therapy in patients with malignant melanoma.

Female↗
PubMed2001

Determination of low thiourea concentrations in industrial process water and natural samples using reversed-phase high-performance liquid chromatography.

A rapid LC method was developed to determine thiourea in natural samples and freshly prepared as well as used tin-baths from the galvanic industry, with LC on a C18-bonded silica column and with doubly distilled water as eluent. The retention time of thiourea is 1.35 min +/- 5%. UV detection is at 236 nm. Small sample volumes of 10-50 microl allow detection down to 2 microg/l thiourea without any interference by heavy metals or organic compounds and in the case of marine samples by mineral salts. The presented technique should be highly useful for industrial purposes.

Calibration↗
PubMed2001

Upregulation of CD40 and CD40 ligand (CD154) in patients with moderate hypercholesterolemia.

BACKGROUND: Hypercholesterolemia, a risk factor for cardiovascular disease, is associated with inflammation and hypercoagulability. Both can be mediated by the CD40 system. This study investigated whether the CD40 system is upregulated in patients with moderate hypercholesterolemia and whether it is influenced by therapy with a hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. METHODS AND RESULTS: Fifteen patients with moderate hypercholesterolemia and 15 healthy control subjects were investigated. CD154 and P-selectin were analyzed on platelets and CD40 was analyzed on monocytes before and under therapy with the statin cerivastatin by double-label flow cytometry. Blood concentrations of soluble CD154 and monocyte chemoattractant protein-1 (MCP-1) were evaluated. Our main findings were as follows. Patients with moderate hypercholesterolemia showed a significant increase of CD154 and P-selectin on platelets and CD40 on monocytes compared with healthy subjects. Soluble CD154 showed a nonsignificant trend for higher plasma levels in patients. A positive correlation was found for total or LDL cholesterol and CD154, but not for CD40 on monocytes. The latter was upregulated in vitro by C-reactive protein, which was found to be significantly elevated in patients with moderate hypercholesterolemia. CD154 on platelets proved to be biologically active because it enhanced the release of MCP-1, which was markedly elevated in an in vitro platelet-endothelial cell coculture model and in the serum of patients. Short-term therapy with a HMG-CoA reductase inhibitor significantly downregulated CD40 on monocytes and serum levels of MCP-1. CONCLUSION: Patients with moderate hypercholesterolemia show upregulation of the CD40 system, which may contribute to the known proinflammatory, proatherogenic, and prothrombotic milieu found in these patients.

Adult↗
PubMed2001

Intestinal absorption of rutin in free and conjugated forms.

Quercetin is one of the most common flavonoids in nature, occurring mainly in glycosidic forms such as rutin. Rutin has been reported to exert numerous biochemical and pharmacological activities, though information about its absorption and metabolism is scarce. The aim of this study was to investigate intestinal handling of luminally administered rutin in an isolated preparation of luminally and vascularly perfused rat small intestine. A synthetic perfusate free from blood components was used as vascular medium, with a perfluorocarbon as oxygen carrier. Luminal media consisted of a bicarbonate-buffered sodium chloride solution spiked with rutin (40.5 +/- 1.8 micromol/L). Viability was maintained during the entire perfusion; no differences between rutin and control perfusions for perfusion pressure, lactate-pyruvate ratio, oxygen uptake, and acid-base homeostasis were observed. About 10% of the administered rutin appeared at the vascular side, chiefly as free rutin (5.6%), but some rutin sulfate (2.5%) and glucuronide (2.0%) were also detected. The conjugates were preferentially absorbed to the vascular side, while only traces of the glucuronide (0.2%) were found in the luminal perfusate. Minute amounts of the rutin administered were located in the intestinal tissue (1.1%) in the form of unchanged rutin and its glucuronide and sulfate conjugates. The model used serves as a valuable tool for understanding intestinal handling of the bioactive flavonol glycoside rutin, and the obtained results confirm uptake of rutin in the rat small intestine.

Animals↗
PubMed2001

Renin uptake by the endothelium mediates vascular angiotensin formation.

We investigated the role of the vascular endothelium in the local production of angiotensin. Angiotensin release from isolated rat hindquarters perfused with an artificial medium was measured by high-performance liquid chromatography and radioimmunoassay. Perfused hindquarters with endothelium released angiotensin I spontaneously, indicating ongoing renin-angiotensinogen reaction. Endothelium denudation (by a detergent, validated by electron microscopy and by the absence of a vasodilator response to acetylcholine) reduced angiotensin I release by >90%, whereas bilateral nephrectomy 24 hours before perfusion abolished the release completely. Infusion of renin into perfused hindquarters induced sustained local angiotensin I release in the presence of an intact endothelium but not after endothelium denudation. The conversion of angiotensin I to angiotensin II was abrogated by endothelium denudation, whereas the disappearance of angiotensin II was unchanged. Endothelium denudation diminished the pressor response to angiotensin II but abolished the response to renin and angiotensin I. Expression of renin messenger RNA, investigated by reverse-transcription polymerase chain reaction using 4 different primer combinations, was not detected in up to 5 microg vascular RNA, whereas a renin signal was readily detected with 5 ng kidney RNA. The effects of endothelium destruction on Ang I formation support the notion that the endothelium mediates vascular angiotensin formation by taking up renin.

Angiotensin I↗
PubMed2000

Influence of the acetification process on phenolic compounds.

Little is known about the change of phenolic compounds and total phenolic content by the acetification process. The aim of this study was to assess the contents of selected phenolic compounds of cider and red and white wines in comparison to phenolic profiles in corresponding vinegars by using a new HPLC method for the simultaneous separation and quantification of polar phenolic acids and less polar flavonoids. Identifications were made by retention times and by means of mass spectra. Additionally, total phenolic contents of wines and vinegars were determined photometrically. The decrease in total phenol content by the acetification process was highest for cider vinegars (40%) and lower for red and white wine vinegars (13 and 8%, respectively). A decrease in the contents of individual phenolic compounds of vinegars from white white and ciders was not observed. In contrast, the contents of individual phenolic compounds in red wine vinegar decreased approximately 50%.

Acetates↗
PubMed2000

[Mistletoe extracts in the therapy of malignant, hematological and lymphatic diseases--a monocentric, retrospective analysis over 16 years].

OBJECTIVE: The aim of the present investigation was to investigate potentials risks of treatment with mistletoe extracts in patients with malignant haematological and lymphatic diseases consulting the Tumour Ambulance of the Community Hospital Herdecke and to evaluate the therapeutic experiences with this treatment. PATIENTS AND METHODS: All 700 patients with these diseases who had been counselled at the Tumour Ambulance of Community Hospital Herdecke since the foundation of the unit were included in a retrospective questionnaire study to collect information on the course of the disease and the survival time. Therapy with mistletoe extracts had been recommended to all patients. The treatment was carried out by the patient's physician outside the hospital. For inclusion into further analysis, information on survival time and mistletoe treatment had to be available. Survival times of patients who had actually received the recommended mistletoe treatment and of patients who had not received the recommended mistletoe treatment were compared (internal comparison). Furthermore, the results were compared to those of conventionally treated patients obtained from the literature (literature comparison). RESULTS: Of 237 patients for whom sufficient data was available, 14 had not been treated with a mistletoe extract. The median survival time was 9.18 years among patients who had received mistletoe compared to 7.54 years among those without. Before a statistical test was carried out, the equivalent distribution of diagnosis in the 2 groups was tested. Regarding this criterion, only 205 patients treated with mistletoe extract and 9 patients not treated with mistletoe extract could be included into the statistical tests of the median survival time. The median survival time was 11.4 years (mistletoe patients) and 8.6 years (patients without mistletoe therapy). The difference was not significant. There were no cases in which mistletoe treatment was associated with deterioration. The comparison with data from the literature yielded very similar survival times among patients not treated with mistletoe extract and those included in our study. CONCLUSION: No indications to risks of a mistletoe therapy on progress of the disease and the survival time could be found. Therefore, no ethical reservations should be opposed to future prospective investigations of mistletoe therapy in patients with malignant haematological diseases.

Female↗
PubMed1999

[Development of lymphocyte subsets in tumor patients after subcutaneous administration of mistletoe extracts].

OBJECTIVE: In order to exclude the possibility that mistletoe therapy may result in immunosuppression, as indicated by a significant reduction of defined lymphocyte subsets, PATIENTS AND METHODS: peripheral blood cells of 23 tumour patients were treated subcutaneously with increasing concentrations of aqueous mistletoe extracts (Helixor(R)). RESULTS AND CONCLUSIONS: Within an observation period of 7 months, the relative amount of lymphocytes and the number of natural killer (NK) cells increased while the number of lymphocyte subsets (i. e. CD19+ B cells, CD4+ T helper cells, CD8+ CD28- suppressor cells, CD8+ CD28+ cytotoxic cells) and the proportion of CD25+ (activated) cells within T cells showed a statistically remarkable trend; due to the multiple test problem of statistical evaluation this trend is not allowed to be termed significant. The leucocytes decreased insignificantly within the observation period. However, we were unable to verify a suggested increase of defined lymphocyte subsets within 2-3 months after the onset of mistletoe treatment. Nevertheless, for the parameters CD19+ B cells, CD4+ T helper cells, CD8+ cells, CD8+ CD28+ cytotoxic cells and CD16+/CD56+ NK cells we observed statistically remarkable peaks within die 2nd and 3rd month of therapy, confirming the hypothesis. The responses to the extracts were obviously interindividually different; the immune responses especially of patients with a lower number of peripheral T cells were less significant as compared to those of patients with adequate T cell numbers. Surprisingly, even an increase of the drug concentration >3 ng mistletoe lectin (as determined within the whole plant extract) per kg body weight enhanced the number of CD4+ T helper cells. A decreased immunological reaction on mistletoe extracts was shown especially for patients with a reduced number of peripheral T cells, whereas patients with normal T-cell number were more reactive.

Adult↗
PubMed1998

Angiotensinases restrict locally generated angiotensin II to the blood vessel wall.

We tested the hypothesis that angiotensinases limit the spillover of locally formed angiotensin II into the circulation. The release of angiotensin peptides from isolated rat hindquarters perfused with an artificial medium was measured by high-performance liquid chromatography and radioimmunoassay. The spontaneous release of angiotensins was increased by the angiotensinase inhibitors phenanthroline (850+/-195 versus 95+/-33 fmol of angiotensin I per 30 minutes in controls, P<.05, n=5 each) and amastatin (P<.05, n=5 each). Infusion of renin induced sustained local angiotensin I formation, which was also increased by phenanthroline. Stimulation of local angiotensin formation by renin infusion was compared with infusion of exogenous angiotensin II. Renin caused similar increases of perfusion pressure (11.1+/-2.2 versus 7.6+/-1.9 mm Hg after angiotensin II, P>.05) despite lower angiotensin II levels in the venous effluent than during infusion of exogenous angiotensin II (65+/-2 versus 482+/-33 fmol/mL, P<.05, n=7 each). Thus, renin must have caused higher angiotensin II tissue levels than indicated by the measurements in the venous effluent. The pressor response to renin was abolished by the type 1 angiotensin II receptor antagonist losartan. We conclude that the major part of locally generated angiotensins is not released into the circulation but degraded by angiotensinases within the tissue compartment.

Angiotensin I↗
PubMed1997

Stimulation of antitumour immunity by intrapleural instillation of a Viscum album L. extract.

Intrapleural administration of mistletoe extracts is reported to result in pleurodesis in cancer patients with malignant pleural effusions. In a recent study, 20 consecutive cancer patients with malignant pleural effusions were treated intrapleurally with the mistletoe extract Helixor. The overall response rate for pleurodesis was 72%, with only 1.2% displaying side effects of the World Health Organization classification I. The decline of tumour cells in the effusion liquid correlated negatively with the number of instillations. However, the elimination of tumour cells was associated with a transient increase in macrophages and eosinophils, and a constant increase in CD8+T cells. Compared to the responder group, the non-responders exhibited high proportions of macrophages, CD8+T cells and T cells with human leukocyte antigens with DR specificity (HLA-DR) in the effusion liquid, compatible with a disturbance of macrophage/T cell co-operation and thus failure to eliminate the malignant cells. The preliminary results suggest that mistletoe-mediated pleurodesis is due to a stimulation of antitumour immunity rather than mechanical sclerosis.

Animals↗
PubMed1993

Preparation and central action of propofol/hydroxypropyl-beta-cyclodextrin complexes in rabbits.

Inclusion complexes of propofol (CAS 2078-54-8) and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) were examined in aqueous solution and in the solid state by phase solubility technique, IR-spectroscopy and differential scanning calorimetry. Solid complexes obtained by kneading method were dissolved in artificial plasma leading to a colloidal solution which was suitable for intravenous administration. In the in vivo studies propofol (15 mg/kg) was given intravenously to rabbits in equimolar doses as cyclodextrin complexes and as Diprivan. The central action of the drug was verified by recording the bioelectrical activity of the precentral cortex. The statistical evaluation of the results do not indicate differences in onset, duration and maximum of action between the two dosage forms.

Animals↗
PubMed1992

Similar central actions of intravenous methohexitone suspension and solution in the rabbit.

The central actions of solutions of methohexitone sodium and suspensions of methohexitone given intravenously in equimolar doses have been compared. The administrations induced identical anaesthesia. Because, in general, drugs acting upon the central nervous system are poorly soluble in water, this finding should be useful for routine pharmacological investigations as it avoids the use of organic solvents which may themselves affect the central nervous system.

Anesthetics↗