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F Otto

Publications and source records attributed to F Otto.

At least 37 records · Page 2Linked to original sources
PubMed1998

Evidence for integrin receptor involvement in megakaryocyte-fibroblast interaction: a possible pathomechanism for the evolution of myelofibrosis.

Megakaryocytes are assumed to be functionally linked with the evolution of myelofibrosis, complicating chronic myeloproliferative disorders. It has already been shown that megakaryocytes will promote fibroblast growth in vitro when in spatial proximity. Here, we demonstrate that the integrin receptors alpha3beta1 and alpha5beta1 are involved in this megakaryocyte-fibroblast interaction. Upon addition of anti-alpha3 and -alpha5 antibodies to megakaryocyte-fibroblast cocultures, fibroblast growth was significantly impaired, and megakaryocyte attachment to the fibroblast feederlayer was significantly reduced. Unilateral blocking of megakaryocytes with anti-alpha3 or -alpha5 antibodies resulted in a suppression of adhesion, probably reflecting the prominent function of fibronectin receptors on the megakaryocyte surface. Moreover, the oligopeptide RGDS (Asp-Gly-Asp-Ser) caused a significant reduction of fibroblast growth as well as megakaryocyte adhesion. This feature reinforces that fibronectin receptors are involved. In addition, fibroblast proliferation was impaired by the application of fibronectin antibodies recognizing the cell-binding domain. However, no effect was observable with respect to megakaryocyte adhesion. In conclusion, our in vitro studies demonstrate the involvement of beta1-integrins, in particular the fibronectin receptor in the megakaryocyte-dependent fibroblast proliferation and therefore suggest a pivotal role of megakaryocytes in the complex pathomechanism causing myelofibrosis.

Adult↗
PubMed1998

Transparent polyamide: a promising new material for microscopic slides.

We report the use of transparent Polyamide as a new material for microscopical slides intended to be used for immunohistochemical stainings. Polyamide slides provide a strongly increased adhesion of the sections compared to conventionally coated glass slides. They are sensitive to mechanical scratches and become turbid during deparaffinization, and revert to transparency within about eight hours. Immunohistochemical stainings for Cathepsin D for which sections from primary cutaneous melanomas are used reflect the results obtained with glass slides, providing well-preserved histology. Other possible applications for slides manufactured from Polyamide include molecular in situ-techniques, such as in situ hybridizations.

Cathepsin D↗
PubMed1998

Hospice care using home-based telemedicine systems.

A pilot study of telenursing for terminally ill patients at home was launched as a collaborative effort between KUMC and the Kendallwood Hospice. The service used the public telephone network. Interactive video equipment was installed in the homes of three nurses who received after-hours calls and in the homes of six hospice patients living in either Kansas or Missouri. Data concerning the utilization patterns were gathered for two separate three-month periods. Patients and caregivers reported general satisfaction with the telehospice system. Both the nurses and social worker providers became comfortable about video-calls. Nurses conducted video-assessments to determine whether an 'in person' visit was necessary. This was particularly helpful for rural patients who were living a long way from the base station. In addition, Kendallwood serves an urban population and, in certain areas, night-time nursing visits raise safety concerns.

Feasibility Studies↗
PubMed1998

Gamma-glutamyltransferase as a marker for the pasteurization of raw milk.

The degree and rate of inactivation of gamma-glutamyltransferase in raw cow's milk by heating at 50, 60, 70, and 80 degrees C for 1, 2, 3, 5, 10, 15, 20, 25, and 30 min were measured to evaluate the suitability of this enzyme as a marker for the pasteurization of milk. The enzymes alkaline phosphatase and lactate dehydrogenase were also measured under similar conditions for comparison. The patterns of heat inactivation of gamma-glutamyltransferase and alkaline phosphatase were similar, with only a minimal inactivation of the enzymes at 50 degrees C. The rate of inactivation increased as a result of increasing temperatures and time. A complete inactivation of both enzymes was seen at 70 degrees C after 10 min and at 80 degrees C after 1 min. Lactate dehydrogenase showed a higher heat resistance with almost complete inactivation at 70 degrees C for 30 min, and compete inactivation at 80 degrees C for 3 min. No activities of these enzymes were found in commercially pasteurized or heat-treated milk. The levels of gamma-glutamyltransferase in raw milk were between 8 and 10% higher than those of alkaline phosphatase and lactate dehydrogenase, making it more sensitive and accurate as a testing marker. It seems that gamma-glutamyltransferase may serve as a good pasteurization marker. Furthermore, the simplicity of testing and the availability of commercial kits for testing by both wet and dry chemistry make it an attractive choice, especially because dry chemistry procedures overcome the difficulties originating from the turbidity of milk, which interferes with spectrophotometric procedures.

Alkaline Phosphatase↗
PubMed1998

Tumor characteristics involved in the metastatic behaviour as an improvement in primary cutaneous melanoma prognostics.

We report the results of a retrospective immunohistochemical study on routinely fixed, paraffin embedded tissues from 147 primary cutaneous melanomas belonging to the classes pT3 and pT4, the development of which has been followed for at least five years. The parameters Cathepsin B, Cathepsin D, Collagenase IV, Metallothionein and PCNA were selected from previous studies on small collectives. All parameters showed statistically significant differences between tumors of the metastatic and the nonmetastatic group. Particularly conspicuous was the expression of Cathepsin B, Cathepsin D and Collagenase IV at the dermal invading front of the tumors. Based on this data we present a procedure of combining these data with established clinical-histological parameters such as tumor thickness and ulceration to an integrated individual risk factor that improves the certainty of melanoma prognosis.

Biomarkers, Tumor↗
PubMed1997

Downregulation of the proinflammatory cytokine response to endotoxin by pretreatment with the nontoxic lipid A analog SDZ MRL 953 in cancer patients.

Interfering with the endotoxin-mediated cytokine cascade is thought to be a promising approach to prevent septic complications in gram-negative infections. The synthetic lipid A analog SDZ MRL 953 has been shown to be protective against endotoxic shock and bacterial infection in preclinical in vivo models. As part of a trial of unspecific immunostimulation in cancer patients, we conducted a double-blind, randomized, vehicle-controlled phase I trial of SDZ MRL 953 to investigate, first, its biologic effects and safety of administration in humans and, second, its influence on reactions to a subsequent challenge of endotoxin (Salmonella abortus equi). Twenty patients were treated intravenously with escalating doses of SDZ MRL 953 or vehicle control, followed by an intravenous application of endotoxin (2 ng/kg of body weight [BW]). Administration of SDZ MRL 953 was safe and well-tolerated. SDZ MRL 953 itself increased granulocyte counts and serum levels of granulocyte colony-stimulating factor (G-CSF) and interleukin-6 (IL-6), but not of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), IL-1beta, and IL-8. Compared with vehicle control, pretreatment with SDZ MRL 953 markedly reduced the release of TNF-alpha, IL-1beta, IL-8, IL-6, and G-CSF, but augmented the increase in granulocyte counts to endotoxin. Induction of tolerance to the endotoxin-mediated cascade of proinflammatory cytokines by pretreatment with SDZ MRL 953 in patients at risk may help to prevent complications of gram-negative sepsis.

Adjuvants, Immunologic↗
PubMed1997

Cbfa1, a candidate gene for cleidocranial dysplasia syndrome, is essential for osteoblast differentiation and bone development.

We have generated Cbfa1-deficient mice. Homozygous mutants die of respiratory failure shortly after birth. Analysis of their skeletons revealed an absence of osteoblasts and bone. Heterozygous mice showed specific skeletal abnormalities that are characteristic of the human heritable skeletal disorder, cleidocranial dysplasia (CCD). These defects are also observed in a mouse Ccd mutant for this disease. The Cbfa1 gene was shown to be deleted in the Ccd mutation. Analysis of embryonic Cbfa1 expression using a lacZ reporter gene revealed strong expression at sites of bone formation prior to the earliest stages of ossification. Thus, the Cbfa1 gene is essential for osteoblast differentiation and bone formation, and the Cbfa1 heterozygous mouse is a paradigm for a human skeletal disorder.

Animals↗
PubMed1997

Mutations involving the transcription factor CBFA1 cause cleidocranial dysplasia.

Cleidocranial dysplasia (CCD) is an autosomal-dominant condition characterized by hypoplasia/aplasia of clavicles, patent fontanelles, supernumerary teeth, short stature, and other changes in skeletal patterning and growth. In some families, the phenotype segregates with deletions resulting in heterozygous loss of CBFA1, a member of the runt family of transcription factors. In other families, insertion, deletion, and missense mutations lead to translational stop codons in the DNA binding domain or in the C-terminal transactivating region. In-frame expansion of a polyalanine stretch segregates in an affected family with brachydactyly and minor clinical findings of CCD. We conclude that CBFA1 mutations cause CCD and that heterozygous loss of function is sufficient to produce the disorder.

Alleles↗
PubMed1996

Phase II trial of intravenous endotoxin in patients with colorectal and non-small cell lung cancer.

We report the immunological and clinical results of a phase II trial with intravenously administered highly purified endotoxin (Salmonella abortus equi) in patients with advanced cancer. 15 patients with non-small cell lung cancer and 27 with colorectal cancer were entered into the study. 37 evaluable patients received at least four injections of endotoxin (4 ng/kg body weight) and 1600 mg ibuprofen orally in 2-week intervals. Transient renal (WHO grade 0-1) and hepatic (WHO grade 0-4) toxicities occurred in several patients. Constitutional side-effects such as fever, chills and hypotension could not be prevented completely by pretreatment with ibuprofen. 3 patients in the colorectal cancer group demonstrated objective responses (1 complete remission (CR), 2 partial remission (PR)). The complete remission has been maintained for more than 3 years, while the partial remissions were stable for 7 and 8 months, respectively. Only marginal antitumour effects were seen in the lung cancer group. Tolerance of the macrophage system to the stimulatory effect of endotoxin, as measured by human necrosis factor alpha (TNF-alpha) release into serum, built up after the first administration and remained at a steady-state level after each subsequent injection. In constrast, rising CD4:CD8 ratio and release of tumour necrosis factor beta (TNF-beta) indicated the continuing activation of the lymphocyte system by repetitive injections of endotoxin.

Adult↗
PubMed1996

Use of the dry chemistry "Reflotron" blood analyzer under outdoor-field conditions in veterinary medicine.

Adapting the concept of "bed-side" patient analysis, the Boehringer-Mannheim Reflotron was evaluated for its possible use in veterinary medicine under outdoor-field conditions. Horse blood was analysed with the Cobas Bio analyzer, and indoor and outdoor analyses were also performed with the Reflotron. All values showed close agreement with no significant differences. Good correlation coefficients (r values around 0.9000) were also seen between all methods used. The Reflotron was operated under outdoor-field conditions by using, whenever available, an on-farm electricity source, or a gas operated generator. The data supports the proposal to adapt the Reflotron (or any other proved system) for outdoor-field, patient-side blood analysis, thus providing the veterinary clinician with values for blood quantities, and enabling an improved and more complete diagnosis.

Analysis of Variance↗
PubMed1996

Interactions between endogeneous lectins and fucosylated oligosaccharides in megakaryocyte-dependent fibroblast growth of the normal bone marrow.

In order to elucidate the involvement of adhesion mechanisms in the process of megakaryocyte-dependent fibroblast growth, we applied BSA-coupled polymers of glucose, galactose, fucose, mannose, and several lectins (AAA, LCA, LTA, UEA-I) to cocultures of CD61 -positive (CD61+)/MACS-enriched megakaryocytes and human bone marrow fibroblasts. Fibroblast monocultures served as controls. After 6 days, glucose, as well as galactose-treated cultures showed a significant reduction of fibroblast growth in cocultures and fibroblast monocultures. In contrast, application of mannose caused no reducing effect on fibroblast numbers. Administration of fucose, AAA, LTA or UEA-I revealed a strong impairment of fibroblast growth in the megakaryocyte-fibroblast cocultures. Adhesion experiments using MACS-enriched, fluorescein-labelled megakaryocytes cultured in the presence of carbohydrates and lectins on a near-confluent layer of fibroblasts were additionally performed. Following fucose-BSA, alpha Fuc-1,2Gal beta-HSA or UEA-I treatment a significant reduction of megakaryocyte adhesion to the fibroblast layer could be observed. In the case of AAA a weak impairment of megakaryocyte adhesion could be noticed. Selective pretreatment of either fibroblasts or megakaryocytes with fucose-BSA or alpha Fuc-1,2Gal beta-HSA was consistent with the finding of a prominent involvement of fucosylated residues located on megakaryocytes in this interaction. In conclusion, our studies are in keeping with the assumption that fucosylated and fucose-binding structures are playing a key role in adhesion mechanisms between megakaryocytes and fibroblasts and thus influence significantly the megakaryocyte-dependent growth of bone marrow fibroblasts.

Adult↗
PubMed1995

Complete response of metastatic renal cell carcinoma to low-dose interferon-gamma treatment.

The course of metastatic renal cell carcinoma may be positively influenced by immunotherapeutic agents. We report a case of renal cell carcinoma showing a complete response to once-weekly low-dose s. c. interferon-gamma (IFN gamma) treatment in multiple metastatic sites (lung, chest wall, abdomen, vertebral body), but concomitantly developing a solitary brain metastasis. High initial interleukin-6 (IL-6) levels returned to normal during IFN treatment suggesting that IFN gamma may have interrupted an autocrine IL-6/IL-6-receptor loop of the tumor cells. The duration of complete remission in the extracerebral sites is now 46+ months. IFN gamma may be less active beyond the blood/brain barrier.

C-Reactive Protein↗
PubMed1995

Endotoxin (Salmonella abortus equi) in cancer patients. Clinical and immunological findings.

1. LPS phase I trial revealed MTD I of 1.0 ng/kg body weight and MTD II of 5.0 ng/kg body weight, the latter given together with ibuprofen (1,600 mg). 2. LPS phase II trial, using 4,0 ng/kg body weight plus ibuprofen in a biweekly schedule didn't show any response in patients with non-small cell lung cancer but 1 CR and 2 PR (13% response rate) in colorectal cancer patients. 3. The LPS tolerance is specific for each cytokine and mediator in regard to the kinetic and degree of its development. INF-gamma prevents the tolerance development to several cytokines with the exception of IL-8. 4. No tolerance was found in cell adhesion, phospholipase A2, and soluble TNF receptor I and II. Priming of ex vivo cytokine production of cytokines was found in mononuclear cells. 5. Synthetic LPS partial structure SDZ-MRL 953 (I) induces a cytokine pattern, which is profoundedly different from that of LPS, (II) with an inverse TNF to G-CSF relation, (III) is (without any ibuprofen treatment) remarkably low toxic, (IV) and downregulates the TNF-response to LPS markedly.

Carcinoma, Non-Small-Cell Lung↗
PubMed1994

Discordant adaptation of human peritoneal macrophages to stimulation by lipopolysaccharide and the synthetic lipid A analogue SDZ MRL 953. Down-regulation of TNF-alpha and IL-6 is paralleled by an up-regulation of IL-1 beta and granulocyte colony-stimulating factor expression.

Human peritoneal macrophages were exposed to increasing doses of LPS or a synthetic lipid A analogue (SDZ MRL 953) and production of the cytokines IL-1 beta, IL-6, TNF-alpha, and G-CSF was assessed at the protein and mRNA level. Cells were also prestimulated with low doses of LPS and SDZ MRL 953 to study their adaptation to a secondary challenge with high doses of LPS. The ability of macrophages to produce high levels of TNF-alpha and IL-6 after stimulation with LPS could be relieved almost completely by preincubating cells with low doses of LPS. Decreases of TNF-alpha and IL-6 production resulted from inhibition of gene transcription and/or changes in mRNA stability, as transcript levels of these cytokines were down-modulated by the process of LPS adaptation. Surprisingly, however, adapted cells were able to synthesize even larger quantities of G-CSF and IL-1 beta when exposed to a secondary LPS challenge. mRNA levels of the adapted cells remained unaltered for IL-1 beta, but were slightly increased for G-CSF as assessed by Northern blot analysis. High doses of the synthetic lipid A analogue SDZ MRL 953 were also able to adapt macrophages to a secondary LPS challenge by down-regulating TNF-alpha and IL-6 production, whereas priming secretion of G-CSF and IL-1 beta as well. We describe here the discordant adaptation of human peritoneal macrophages to a secondary LPS stimulus in vitro. These findings appear to have ramifications for the in vivo endotoxin response during inflammation and also Gram-negative septicemia.

Dinoprostone↗
PubMed1993

The prognosis of patients with stage III melanoma. Prospective long-term study of 286 patients of the Fachklinik Hornheide.

BACKGROUND: Prognostic factors for patients with stage III melanoma are still controversial. METHODS: Two hundred eighty-six patients with solitary cutaneous malignant melanoma of the skin in Stage III (International Union Against Cancer [UICC]) were followed up for as long as 11 years. RESULTS: Patients in risk group pT 4a, pN O (primary tumor thickness of more than 4 mm or invasion of subcutis and absence of regional lymph node metastasis in elective lymph node specimen) have a 5-year survival rate of 72.8%. If regional metastases are excluded clinically (pT 4a, NO), the 5-year survival rate is 62.8%. Patients with regional lymph node metastases have an average 5-year survival rate of 39%, depending mainly on the number of involved lymph nodes and the depth infiltration of the primary tumor. The number of involved lymph nodes reflects the grade of dissemination. It shows a stronger correlation with the prognosis than does the size of metastases. CONCLUSIONS: The authors recommend that revisions of the UICC classification should distinguish Stage IIIA and IIIB based on the presence or absence of regional metastases and that a clearer distinction should be made between regional cutaneous or subcutaneous metastases and regional lymph node metastases.

Adult↗
PubMed1993

Analytic morphology in clinical and experimental dermatology.

During the past several years, quantitative morphology has gained increasing attention in diagnostic pathology and in certain research applications. In the field of dermatopathology, quantitative morphology has been applied to numerous problems, ranging from the interactive measurement of nuclear contours to fully automated, high-resolution image analysis of ultrastructural micrographs. Dermatologic applications are reviewed, and potential developments in the future are briefly outlined.

Animals↗
PubMed1992

Bromodeoxyuridine hypersensitivity of metastatic melanoma cells.

A model system for testing the efficacy of chemotherapy protocols for metastatic melanoma was established using cell cultures from two brain and three lymph node metastases of melanoma from five different patients. Continuously growing cultures which were positive for tyrosinase activity were analysed regarding their proliferation rate by continuous bromodeoxyuridine (BrdU) labelling and subsequent Hoechst-33258/ethidium bromide flow cytometry. Melanoma cell cultures exhibit a strong sensitivity to BrdU: at 5% oxygen, 50% growth inhibition is attained with 360 +/- 130 microM BrdU (range: 130-520; n = 11) vs 650 +/- 50 microM BrdU (n = 3) for diploid human fibroblasts and 570 +/- 20 microM BrdU (n = 6) for human lymphoid cell lines. Moreover, BrdU sensitivity of melanoma cells is clearly oxygen dependent: 50% growth inhibition at 200 +/- 55 microM (range: 65-400 microM) for 20% oxygen vs 360 +/- 130 microM BrdU for 5% oxygen. The cell cycle kinetic mechanism of BrdU-induced growth inhibition is accumulation of cells in the first cycle G2 phase. On the basis of these results we suggest testing BrdU in chemotherapy protocols for the treatment of metastatic melanoma.

Brain Neoplasms↗