Biomedical subjects

H Wagner

Publications and source records attributed to H Wagner.

At least 37 records · Page 2Linked to original sources

PubMed2003

A multimodal treatment approach including high-dose chemotherapy in very advanced gastric cancer: evidence for control of metastatic disease.

The present multimodal treatment approach was designed to achieve prolonged tumor control in advanced gastric cancer. A total of 26 patients with stage IV gastric cancer (metastatic disease n=25), ECOG performance status 0-3 and laparoscopically evaluated peritoneal status received a modified EAP schedule to prove chemosensitivity and to mobilize autologous peripheral blood stem cells (aPBSC). Patients without progressive disease proceeded to tandem high-dose chemotherapy (HD-CT) and aPBSCT. Patients with >50% reduction of the target lesion received a second cycle of HD-CT. Responders were selected for local R0 resections (D2 resection) according clinical criteria. Of 26 patients, 20(77%) achieved partial remission after dose-intensive chemotherapy: local R0 resection was achieved in 12 out of 14 patients selected for surgery (46% of all patients). Eight of these R0-resected patients initially had peritoneal carcinomatosis. With a median follow-up of 3.2 years, four patients are still alive. The median overall survival was 8.4 months (CI 2.5-14.4 months), for histologic regression grade 3 (seven out of 25 patients, 28%) 29 months (CI 12-46 months). The combined treatment approach is tolerable and feasible in advanced disease and opens a therapeutic window for a significant proportion of patients, even in cases with histologically proven peritoneal carcinomatosis.

Adult↗

PubMed2003

Toll-like receptor (TLR) 2 and TLR4 are essential for Aspergillus-induced activation of murine macrophages.

Aspergillus fumigatius is a ubiquitous saprophytic fungus that has become the most prevalent airborne fungal pathogen for immunocompromised patients during the last two decades. In this report we have analysed how macrophages recognize this microorganism. Using transfected human HEK 293 cells we demonstrate that NF-kappaB-dependent promoter activation triggered by A. fumigatus is mediated by Toll-like receptors TLR2 and TLR4, whereas no activation was observed in cells overexpressing other distinct TLR proteins (TLR1, TLR3, TLR5-10). Using macrophages derived from mice lacking TLR2 expression, expressing defective TLR4 or both we found that A. fumigatus conidia and hyphae induce NF-kappaB translocation, release of pro-inflammatory molecules, like TNFalpha, and the chemoattractant MIP-2 in a TLR2- and TLR4-dependent manner. Recognition of A. niger and A. fumigatus, was similar in terms of the parameters analysed, suggesting that pathogenic and non-pathogenic aspergilli are sensed by macrophages in a similar fashion. Finally, we found that recruitment of neutrophils is severely impaired in mice lacking both functional TLR2 and TLR4, but is less impaired in single TLR2- or TLR4-deficient mice, providing evidence that both receptors are required for an optimal immune response to Aspergillus in vivo.

Active Transport, Cell Nucleus↗

PubMed2003

Immunologically active O6-branched (1-->3)-beta-glucan from the lichen Thamnolia vermicularis var. subuliformis.

A lentinan-type gel-forming beta-glucan, Ths-2, has been isolated in about 1.5% yield from the alkali extract of the lichen Thamnolia vermicularis var. subuliformis, using ethanol fractionation, dialysis and gel filtration. The mean Mr of Ths-2 was determined by GP-HPLC to be 67 kD, and the optical rotation was measured to be -14 degrees. The structure of Ths-2 was further elucidated by methylation analysis by GC-MS, 1H- and 13C-NMR spectroscopy and selective enzymatic hydrolysis with exo-(1 --> 3)-beta-D-glucanase followed by analysis of oligosaccharides by HPAEC-PAD. Ths-2 was found to be consisting of a (1 --> 3)-beta-D-glucopyranosyl main chain with branches of a (1 --> 6) linked glucopyranosyl unit on every third unit of the main chain. Similar polysaccharide structures have been described from fungi, but this is the first report of a lentinan-type (1 --> 3)-beta-D-glucan from a lichen species. The immunomodulating activity of Ths-2 was tested in an in vitro anti-complementary assay, and proved to be strongly active.

Animals↗

PubMed2002

Distribution of auditory motion-direction sensitive neurons in the barn owl's midbrain.

Barn owls have neurons sensitive to acoustic motion-direction in the midbrain. We report here that acoustic motion-direction sensitive neurons with receptive-field centres in frontal auditory space are not randomly distributed. In the inferior colliculus and optic tectum in the left (right) brain, the responses of about two-thirds of the motion-direction sensitive neurons were sensitive to clockwise (counter-clockwise) motion. The midbrain contains maps of auditory space that represent about 15 degrees of ipsilateral and all of contralateral space. Since a similar bias in motion-direction sensitivity was observed for neurons with receptive-field centres in ipsilateral as well as for neurons with receptive fields centres in contralateral auditory space, the brain side at which a motion-direction sensitive neuron was recorded was a more important predictor for the preferred direction of a cell than the spatial direction of the centre of the receptive field. Within one dorso-ventral electrode pass motion-direction sensitivity typically stayed constant suggesting a clustered or even a columnar-like organization. We hypothesize from these distributions that the right brain is important for orientating movements to the left hemisphere and vice versa.

Acoustic Stimulation↗

PubMed2002

Helicobacter pylori-stimulated EGF receptor transactivation requires metalloprotease cleavage of HB-EGF.

Helicobacter pylori has a major aetiological role in human gastric carcinogenesis but the cellular and molecular pathways by which infection promotes transformation remain to be resolved. This study demonstrates that H. pylori exposure to MKN-1, ST42, and MKN-28 gastric epithelial tumour cells results in the activation of HB-EGF gene expression and EGFR tyrosine phosphorylation. These cell responses are induced by both cagPAI positive and cagPAI negative H. pylori strains and are dependent on cell surface expression of the HB-EGF precursor. The induction of HB-EGF gene transcription by H. pylori requires metalloprotease-, EGFR-, and Mek1-activities, indicating the involvement of the "triple membrane passing signal" (TMPS) for EGFR transactivation. Moreover, the release of the inflammatory cytokine IL-8 by cells exposed to H. pylori is significantly impaired by inhibitors of TMPS pathway elements. Our findings support a model in which H. pylori triggers constitutive EGFR signal activation, which enhances IL-8 production, and initiates neoplastic transformation of gastric epithelial cells.

Blotting, Northern↗

PubMed2002

Vasodilating properties of extracts from the leaves of Musanga cecropioides (R. Brown).

The mechanisms of action involved in the hypotensive properties of the aqueous extract of the leaves of Musanga cecropioides were investigated. The effect of the aqueous leaf extract of M. cecropioides, found to contain mostly saponins, flavonoids and procyanidins, was investigated on vascular smooth muscle and also in an in vivo direct invasive blood pressure study in both normotensive and hypertensive rats. The hypotensive or antihypertensive properties of the extracts appear to be due partly to a direct or indirect vasodilator effect and also to some alpha(1)- and beta(2)-adrenergic blocking effects. The extract also exhibited significant endothelium-dependent vascular smooth muscle relaxation, accounted for by the release of nitric oxide (NO), and induced significant angiotensin converting enzyme (ACE) inhibitory effects thereby supporting its vasodilator mechanism of action.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2002

Heat shock proteins as ligands of toll-like receptors.

Toll-like receptors (TLRs) have been described as sensors for pathogen-associated molecular patterns crucial for the initiation of an innate immune response. These mechanisms were developed long before the adaptive immune system evolved. The latest additions to the growing list of TLR ligands are heat shock proteins (HSPs). Interestingly, not only bacterial but also mammalian HSPs interact with TLRs demonstrating that the exclusive association of TLRs with microbial ligands is obsolete. Human HSP60 and Gp96 are the first examples of non-pathogen derived ligands of TLRs. More importantly, Gp96 provides the first example of how the innate and adaptive immune system can be stimulated simultaneously by the same molecule which is released under physiological conditions from necrotic cells. Understanding the mechanisms of innate immune system interaction with HSPs will make it possible to rationally modulate immune responses, either towards immunity or towards tolerance.

Animals↗

PubMed2002

Bacterial CpG-DNA licenses TLR9.

The family of Toll-like receptors (TLRs) plays an important role in the innate immune response to pathogens. TLRs sense pathogen associated molecular patterns (PAMP) and lead to the stimulation of immune cells. In man, so far ten members (TLR1-10) have been reported. This review focuses on TLR9 which is an essential component for the recognition of bacterial CpG-DNA. Expression of TLR9 and structural consideration as well as direct ligand interaction of TLR9 and CpG-DNA are discussed.

Animals↗

PubMed2002

The influence of gender on survival and tumor recurrence following adjuvant therapy of completely resected stages II and IIIa non-small cell lung cancer.

This study evaluates the influence of gender on survival and tumor recurrence following adjuvant therapy of completely resected stages II and IIIa non-small cell lung cancer (NSCLC). The Eastern Cooperative Oncology Group conducted a randomized prospective trial of adjuvant therapy in patients with completely resected stages II and IIIa NSCLC. A laboratory correlative study assessed the prevalence and prognostic significance of p53 and K-ras mutations. Patients were randomized to receive either radiotherapy (RT) alone or four cycles of cisplatin and VP-16 administered concurrently with radiotherapy (CRT). Median survival was 35 months for the 285 men and 41 months for the 203 women enrolled in the study (P = 0.12). The relative risk (RR) of death for men vs women was 1.19 (95% confidence interval [CI], 0.95-1.49). Median survival of the 147 men and 95 women randomized to the RT arm was 39 months each (P = 0.35). Median survival of the 138 men and 108 women randomized to the CRT arm was 30 and 42 months, respectively (P = 0.18). Disease recurrence patterns were similar between the genders. Univariate and multivariate analyses demonstrated improved survival for women with tumors of non-squamous histology (P < 0.01). The distribution of p53 and K-ras mutations was similar between the genders and had no influence on survival. Gender does not influence survival following adjuvant RT or CRT administered to patients with completely resected stages II and IIIa NSCLC. However, women with non-squamous histology have increased survival when compared to men.

Adult↗

PubMed2002

Morphometry of auricular feathers of barn owls (Tyto alba).

In all owl species, the facial plumage forms a parabolic dish, the facial ruff, which is most conspicuous in the the barn owl (Tyto alba). The center of the ruff is formed by auricular feathers. Such feathers are also found on the preaural flaps which cover the ear openings, and in the region of the beak. In this study, we compare the different types of auricular feathers of the barn owl with contour feathers from the neck. Auricular feathers are characterised by an open vane structure and fewer barbs as compared to contour feathers. Auricular feathers also have fewer distal and proximal barbules than contour feathers. The open vane of the auricular feather results from an acute angle between the barb and the basis of the barbules, and from the extension of the pennula parallel to the barbs. These reductions are differently expressed in the three different types of auricular feathers investigated here and correspond with their function (protecting the ruff from dust).

Animals↗

PubMed2002

Estrogenic and cholinergic properties of the methanol extract of Ruellia praetermissa Sceinf. ex. Lindau (Acanthaceae) in female rats.

In search for alternative drugs with pharmacological profile to replace hormone replacement therapy, the effects of MeOH extract of Ruellia praetermissa on the uterus and gestation in rats was investigated. 350 mg/kg/day of extract from days 1-9, 1-17 and 9-17 respectively, resulted in increase of the number of implantation sites (56 to 64) and the percentage of implantation (68.6 +/- 2.7 to 90.5 +/- 0.5%). There was also an increase in body weight (1-9 and 1-17) followed by a slight decrease (154 +/- 15.5 to 125 +/- 10) in the body weight at term. The number and the mean value of corpora lutea per female decreased from 25.4 +/- 1.6 to 14.00 +/- 1.6. The extract produced dose-related contraction of the isolated uterine muscle in vitro comparable to ACh. Atropine in doses from 3.4 x 10(-6) to 3 x 10(-3) microM antagonized the response of the uterus to ACh at 2 microM. It induced an increase (0.03 +/- 0.002 to 0.34 +/- 0.001 g) of the uterine weight comparable to that produced by using 3 microM estradiol (0.03 +/- 0.001 to 0.35 +/- 0.005 g). It could therefore be postulated that this extract possesses estrogenic and possible cholinergic effects. The estrogenic effect could have been generated by plant sterols (beta-sitosterol and stigmasterol) and flavonoids (luteolin and apigenin) while cholinergic effect could be due to iridoid glycosides.

Acanthaceae↗

PubMed2002

A double blind, placebo-controlled study of Andrographis paniculata fixed combination Kan Jang in the treatment of acute upper respiratory tract infections including sinusitis.

A double blind, placebo-controlled, parallel-group clinical study was carried out to evaluate the effect of an Andrographis paniculata (N.) extract SHA-10 fixed combination, Kan Jang, in the treatment of acute upper respiratory tract infections, including sinusitis. Ninety-five individuals in the treatment group and 90 individuals in the placebo group completed the study according to the protocol. The medication was taken for 5 days. Temperature, headache, muscle aches, throat symptoms, cough, nasal symptoms, general malaise and eye symptoms were taken as outcome measures with given scores. The total score analysis showed a highly significant improvement in the verum group versus the placebo. This result applied to the group as a whole and to the sinusitis subgroups. The individual symptoms of headache and nasal and throat symptoms together with general malaise showed the most significant improvement while cough and eye symptoms did not differ significantly between the groups. Temperature was moderately reduced in the verum group. It can be concluded that Kan Jang has a positive effect in the treatment of acute upper respiratory tract infections and also relieves the inflammatory symptoms of sinusitis. The study drug was well tolerated.

Acute Disease↗

PubMed2002

Immunological studies of Revitonil, a phytopharmaceutical containing Echinacea purpurea and Glycyrrhiza glabra root extract.

A phytopharmaceutical containing an extract of Echinacea purpurea and Glycyrrhiza glabra root (Revitonil tablets) was investigated for its suggested immunostimulating potential, using several in vitro tests and the in vivo carbon-clearance model in mice. In the in vitro phagocytosis test with human granulocytes, Revitonil showed a 44-53% stimulating effect at a concentration of 100 microg/ml. Whereas in the chemoluminescence test at a concentration of 1.25 microg/ml, Revitonil tablets exhibited a moderate enhancing effect only, a remarkable stimulating activity (30-50%) was observed in the T-lymphocyte CD69 bioassay at a concentration of 100 microg-1 microg/ml. The highest immunological efficacy could be assigned to Revitonil as revealed by the in vivo carbon-clearance model in mice. With RCt/RCc-values of 2.0, Revitonil exhibited a very high carbon elimination rate at oral administration. Because the Echinacea and Glycyrrhiza monoextracts alone showed lower RCt/RCc-values (1.3-1.7) than Revitonil, a potentiating synergistic effect of the extract mixture in Revitonil can be postulated.

Chromatography, High Pressure Liquid↗

PubMed2002

Prognostic value of tumour cell detection in peripheral blood of breast cancer patients.

To investigate the prognostic value of tumour cells in peripheral blood (pB) of breast cancer (BC) patients, pB samples from 143 patients with benign lesions of the breast and from 467 BC patients were tested via a nested RT-PCR assay for mammaglobin mRNA. No sample from patients with benign lesions of the breast was found to be mammaglobin positive in contrast to 5/310 (2%) BC patients with no evidence of disease (NED) and 46/157 (29%) patients with metastatic disease (MD). Two hundred and eighteen BC patients with NED were followed for at least 12 months. All five mammaglobin-positive BC patients relapsed 1-13 months after first examination of positive pB samples in contrast to 27/213 (13%) patients without detectable tumour cells in pB. Fifty-nine BC patients with MD were tested for mammaglobin expression in pB at the time of first diagnosis of MD; 20 of them (34%) were mammaglobin positive. Patients were followed for a median of 19 months (2-51 months). During this time, 19/59 (32%) died due to tumour progression. In Kaplan-Meier survival analysis, BC patients with mammaglobin-negative pB samples at time of diagnosis of MD lived significantly longer than mammaglobin-positive patients (log-rank test: P = 0.0013). In addition, mammaglobin was an independent prognostic parameter and the difference reached significance in univariate as well as in multivariate analysis (P < 0.01). We conclude that the presence of tumour cells in pB of BC patients is of prognostic value.

Adult↗

PubMed2001

A threshold explains modulation of neural responses to opposite-contrast stereograms.

Disparity-sensitive neurons respond to contrast-inverted stereograms (aRDS) that do not evoke depth percepts. This is in conflict with the idea that such neurons are the direct correlate of depth perception. However, the output of neurons responding to aRDS may be further processed: neurons at later processing stages show weaker responses to aRDS than early stage neurons. Here, we show that such a response hierarchy emerges in a three-layered neural network. A numerical analysis demonstrates that threshold operations can largely explain the network's behavior as well as the electrophysiological data. An extension of the energy neuron model for disparity-sensitive neurons predicts increased responses to aRDS for an identifiable sub-class of cells and can thus be tested in electrophysiological experiments.

Action Potentials↗

PubMed2001

Predominant role of toll-like receptor 2 versus 4 in Chlamydia pneumoniae-induced activation of dendritic cells.

Chlamydia pneumoniae is an obligate intracellular human pathogen causing diseases such as pneumonia, bronchitis, and pharyngitis. Because of its intracellular replication, cell-mediated immune responses are needed to mediate successful defenses of the host. Because dendritic cells play a central role in linking innate immunity and Ag-specific cell-mediated immune responses we asked whether dendritic cells are activated upon contact with C. pneumoniae and whether known Toll like receptors (TLR) are involved in this process. Here we show that C. pneumoniae was taken up by bone marrow-derived murine dendritic cells. Ingested C. pneumoniae appeared to be unable to develop mature inclusion inside dendritic cells. Furthermore, upon contact with C. pneumoniae dendritic cells were potently stimulated because NF-kappaB was activated and translocated to the nucleus, cytokines like IL-12p40 and TNF-alpha were secreted, and expression of MHC class II molecules, CD40, CD80, and CD86 was up-regulated. Importantly, secretion of cytokines as well as translocation of NF-kappaB were dependent on the presence of TLR2 and independent from TLR4 with the exception of IL-12p40 secretion, which was attenuated in the absence of either a functional TLR2 or 4. In conclusion, we show here that recognition of the Gram-negative bacterium C. pneumoniae depends largely on TLR2 and only to a minor extent on TLR4.

Active Transport, Cell Nucleus↗

PubMed2001

Interrelation of permeation and penetration parameters obtained from in vitro experiments with human skin and skin equivalents.

In a comparative study, two different in vitro cutaneous test systems were examined: (1) The Franz diffusion cell (FD-C), a test system to study drug permeation through the skin and to obtain data like steady state flux and lag time as well as permeability and diffusion coefficients. (2) The Saarbruecken penetration model (SB-M), a test system to investigate drug penetration into different skin layers and after varying incubation times to acquire values about the quasi steady state drug amounts in the stratum corneum (SC). Three drug concentrations (0.9, 0.45 and 0.225%) of a lipophilic model drug preparation, flufenamic acid in wool alcohols ointment, were applied on the skin's surface using 'infinite dose' conditions. Trypsin-isolated SC, heat-separated epidermis, full-thickness skin and reconstructed human skin (RHS) served as skin membranes in the FD-C, while the SB-M experiments were only carried out using full-thickness skin. Increasing steady state flux data and m(ss) values (steady state drug amount in the SC) were detectable after the application of rising drug amounts. Concerning the permeability of the used skin membranes in establishing barrier properties, the following rank order was observed: RHS>SC> or =epidermis>full skin. The flux data of the FD-C experiments for isolated SC, separated epidermis and RHS were linearly related with the m(ss) values of the SB-M investigations, allowing a direct comparison of permeation with penetration parameters. Concerning the drug amount in the SC, previous investigations succeeded in the establishment of an in vivo/in vitro correlation. Based on the results presented here, the prediction of drug amounts present in the SC after different incubation times in vivo is now possible after penetration as well as permeation experiments using the lipophilic model drug preparation, flufenamic acid in wool alcohols ointment.

Epidermis↗

PubMed2001

Quality of life assessment in advanced non-small-cell lung cancer patients undergoing an accelerated radiotherapy regimen: report of ECOG study 4593. Eastern Cooperative Oncology Group.

PURPOSE: To prospectively evaluate the quality of life (QOL) before, at completion, and after therapy for patients receiving an accelerated fractionation schedule of radiotherapy for advanced, unresectable non-small-cell lung cancer in a Phase II multi-institutional trial. METHODS AND MATERIALS: The Functional Assessment of Cancer Therapy-Lung (FACT-L) patient questionnaire was used to score the QOL in patients enrolled in the Eastern Cooperative Oncology Group Phase II trial (ECOG 4593) of hyperfractionated accelerated radiotherapy in non-small-cell lung cancer. Radiotherapy (total dose 57.6 Gy in 36 fractions) was delivered during 15 days, with three radiation fractions given each treatment day. The protocol was activated in 1993, and 30 patients had accrued by November 1995. The FACT-L questionnaire was administered at study entry (baseline), on the last day of radiotherapy (assessment 2), and 4 weeks after therapy (assessment 3). The FACT-L includes scores for physical, functional, emotional, and social well-being (33 items), and a subscale of lung cancer symptoms (10 additional items). The summation of the physical, functional, and lung cancer symptom subscales (21 items) constitutes the Trial Outcome Index (TOI), considered the most clinically relevant outcome measure in lung cancer treatment trials. RESULTS: The FACT-L completion rates at the designated study time points were as follows: baseline, 30 of 30 (100%); assessment 2, 29 (97%) of 30; and assessment 3, 24 (80%) of 30. At treatment completion, statistically significant declines in QOL scores were noted, compared with baseline for physical and functional well-being. Emotional well-being scores improved at both assessment 2 and assessment 3. The physical and functional scores returned approximately to baseline values at assessment 3. The change in TOI score was evaluated as a function of the clinical response to treatment, toxicity grade, and survival; no clear association was noted. A trend for the largest decrease in QOL was noted for patient groups with shorter survival times. The mean change in the TOI score from baseline to assessment 3 was -8.96 for patients surviving < 52 weeks vs. -0.95 for those surviving > 52 weeks. CONCLUSIONS: The FACT-L questionnaire can be successfully administered to non-small-cell lung cancer patients enrolled in a prospective Phase II trial of accelerated radiation fractionation. The decrement in physical and functional QOL during treatment returned to baseline level at 4 weeks after treatment. Emotional well-being improved at all time points. A trend was noted for shorter survival times in patients with the largest negative change in TOI score. These data suggest that the clinical use of hyperfractionated accelerated radiotherapy did not cause a significant, long-term decrease in the QOL of the treated patients, and that it is feasible to perform a QOL study of patients enrolled in such a trial.

Activities of Daily Living↗