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Biomedical subjects

D Huhn

Publications and source records attributed to D Huhn.

At least 145 records · Page 8Linked to original sources

Aerosol amphotericin B for prevention of invasive pulmonary aspergillosis.

The pharmacokinetics and applicability of aerosol amphotericin B administrations were studied in 40 neutropenic patients and 4 healthy volunteers. Particle size was measured and pulmonary deposition was demonstrated by radioisotope studies. Inhalations were easy to administer and were well tolerated, with minimal systemic absorption of the drug.

Administration, Inhalation↗

Recombinant human erythropoietin in patients with myelodysplastic syndrome and myelofibrosis.

In a dose titration study we tested the efficacy and tolerance of recombinant human erythropoietin (rhEPO) in 10 patients with myelodysplasia (MDS) and 2 patients with idiopathic myelofibrosis. Patients with a haemoglobin level < 100 g/l were treated as out-patients for 12 weeks with daily doses ranging from 30 U/kg body weight (BW) up to 240 U/kg BW in non-responders. Of the 10 patients with MDS, 6 were suffering from refractory anaemia with sideroblasts (RAS) and 4 from refractory anaemia with an excess of blasts. The median age was 73 years (range 41-81). Two patients with RAS responded with a rise in haemoglobin concentration to > 130 g/l. They had not been transfusion-dependent prior to treatment. Both patients had relatively low serum concentrations of immunoreactive EPO. There was neither a rise in haemoglobin nor a reduction in transfusion dependence in any of the other patients. It may be concluded that rhEPO is possibly effective in a subgroup of MDS patients where the disease is less advanced. None of the transfusion-dependent patients benefited.

Adult↗

Position specificity of Ki-ras oncogene mutations during the progression of colorectal carcinoma.

The Ki-ras proto-oncogene is converted into an active oncogene by mutations in codon 12, 13, or 61. The incidence of mutations in the Ki-ras oncogene in colorectal adenomas and primary colorectal carcinomas has been shown to be 50-75 and 40-65%, respectively. To determine the role activation of the Ki-ras oncogene plays in the progression of colorectal carcinoma, we analyzed DNA from 11 nude-mouse xenografts and from 24 metastases of 22 patients with colorectal carcinoma, using the polymerase chain reaction technique and hybridization with labeled mutation-specific oligomers. Eleven of the 24 metastases (46%) carried mutations, 7 in codon 12 and 4 in codon 13, whereas only 1 nude-mouse tumor (9%) harbored a Ki-ras codon-12 mutation. Eleven of these 12 mutations in advanced stages of colorectal cancer were localized to the second position of either codon 12 or codon 13, whereas a majority of published ras mutations in earlier stages are in the first position of codon 12 of the Ki-ras oncogene. We conclude that there is a position specificity of Ki-ras oncogene mutations in advanced stages of colorectal carcinoma. In general, however, these mutations do not seem to play an important role in the progression of this cancer.

Amino Acid Sequence↗

[Optimizing leukocytapheresis for collection of circulating hematopoietic stem- and precursor cells by multiparameter flow cytometry].

Peripheral blood stem cells are an alternative to bone marrow-harvested stem cells. We report on the feasibility of predicting optimal timing for leukapheresis by means of blood monitoring for CD34-positive cells by flow cytometry. In addition to monitoring, determinations of CD34-positive cells also are predictive for the hemopoietic potency of cells harvested by leukapheresis, as close correlations of numbers of CFU-GM and of CD34-positive cells, respectively, in leukapheresis samples are determined. Our data are indicating that flow-cytometrical determinations of CD34-positive cells are helpful in the setting of blood stem cell harvesting by leukapheresis, both for optimal timing of the procedure and for real-time estimation of the hemopoietic potency of cells harvested.

Antigens, CD↗

Phenotypic characterization and identification of effector cells involved in tumor cell recognition of cytokine-induced killer cells.

Cytokine-induced killer (CIK) cells are highly efficient cytotoxic effector cells capable of lysing tumor cell targets. Cultures of human CIK cells have been shown to have enhanced cytotoxicity and to proliferate more rapidly than lymphokine activated killer (LAK) cells by both in vitro and in vivo studies. In this report, we have further characterized the phenotype of CIK cells and explored the molecular structures involved in CIK-mediated cell lysis of tumor target cells. The dominant cell phenotype in CIK cell cultures expresses the alpha, beta T cell receptor (TCR-alpha/beta). In addition, CD56 is expressed on the main effector cell on a per-cell basis. Interestingly, the total number of CD56+ cells increases more than 1000-fold during the generation of CIK cells, mainly due to expansion of CD56+ cells coexpressing CD3. The higher lytic activity of CIK cells as compared to LAK cells is mainly due to the higher proliferation of CD3+CD56+ cells and to the cytotoxic activity of TCR-alpha/beta+ cells in CIK cell cultures. CIK-mediated cellular lysis is non-major histocompatibility antigen (MHC) restricted. The cytotoxic effect of CIK cells against tumor targets is blocked by antibodies directed against lymphocyte function-associated antigen (LFA-1) and its counter receptor, intercellular adhesion molecule-1 (ICAM-1).

Animals↗

Microcirculatory effects of hyperthermia and 5-fluorouracil in the skin of nude mice.

During cancer chemotherapy physical manipulation of skin perfusion by hyperthermia can limit therapeutic efficacy. Because it is important to know microcirculatory responses to those forms of treatment, we used the ear of the lightly or not at all anesthetized nude mouse (rnü/rnü). To test, if whole body hyperthermia (WBH) and 5-fluorouracil (5-FU) acutely affect skin microvessels, we applied red light (group 1). 5-FU was injected prior to WBH, to test for effects of 5-FU on WBH (group 2). Respiratory rate increased and medium sized and small arterioles constricted during WBH in both groups and cutaneous perfusion decreased. 5-FU did not change these results. There were more leucocytes rolling along the vessel wall of small and medium-sized venules after 5-FU treatment (compared to BL). Our data suggest that activation of sympathetic tone by an external heat source compromises skin perfusion and could decrease the amount of cytostatic agents to that organ during WBH. Finally, there is more intense interaction among leucocytes and endothelial cells omit in response to 5-FU.

Animals↗

[Diffuse demineralization of the lumbar spine. Magnetic resonance tomography studies of osteoporosis and plasmacytoma].

On plain radiographs, diffuse infiltration of the spine in multiple myeloma may present as diffuse demineralization. Differentiation from osteoporotic changes is then difficult. 15 patients with multiple myeloma and 15 patients with osteoporosis were prospectively examined by MRI using plain and contrast enhanced gradient echo techniques. Examinations were evaluated for lesions and diagnosis was made by two independent observers. Contrast enhancement was visible in lesions detected in myeloma patients and in compression fractures. Fractures could be differentiated from malignant lesions by the fact that there was no multiplicity of enhancing lesions. Contrast enhanced opposed phase gradient echo sequences seem suited for the detection of vertebral involvement in myeloma.

Adult↗

Genetic alterations in the p53 gene in the blast crisis of chronic myelogenous leukemia: analysis by polymerase chain reaction based techniques.

Rearrangements of the c-abl protooncogene and the bcr-gene are found in > 90% of patients in chronic phase of chronic myelogenous leukemia (CML). The molecular events leading to blast crisis, however, have not been well characterized. Gross alterations of the p53 gene have been detected in 30% of patients with blast crisis. Since point mutations in the p53 gene appear to be important in the process of transformation in many epithelial tumors, we looked for these mutations in the critical regions of the p53 gene (exons 4, 5, 6, 7, and 8). We used the polymerase chain reaction (PCR), direct sequencing, differential PCR, and single strand conformation polymorphism (SSCP) analysis to detect mutations of the p53 gene in samples from 21 patients with CML blast crisis. Two of 21 patients exhibited an intragenic deletion or rearrangement in p53. In addition, these patients were homozygous for the mutant p53 allele. No mutations were found in the p53 gene of the remaining 19 patients. However, sequencing of the CML blast crisis cell line, K562, revealed an insertion of a C at base position 956 within the fifth exon, causing a frame shift mutation and an early translational stop at codon 148. We conclude that, in contrast to solid tumors, mutations in exons 4-8 of p53 are not frequently seen in primary samples from CML blast crisis. However, deletions and/or rearrangements within the p53 gene do occur and may contribute to the progression from chronic phase to blast crisis in a limited number of patients with CML.

Base Sequence↗

Treatment of angioimmunoblastic lymphadenopathy (AILD)-type T-cell lymphoma using prednisone with or without the COPBLAM/IMVP-16 regimen. A multicenter study. Kiel Lymphoma Study Group.

OBJECTIVE: To describe the clinical course of patients with angioimmunoblastic lymphadenopathy (AILD)-type lymphoma with a sequential treatment with prednisone and COPBLAM/IMVP-16. DESIGN: A multicenter, prospective, nonrandomized trial. SETTING: University medical centers and community hospitals. PATIENTS: Sixty-seven patients were registered, 28 were excluded, and 39 patients were evaluable for response (median age, 59 years; range, 25 to 82 years) (stages I and II, 10%; stages III and IV, 90%; B symptoms, 74%). MEASUREMENTS: Response, survival, and relapse. INTERVENTION: Patients initially received prednisone and no further treatment if a complete remission was achieved. Relapsing or refractory patients were treated with COPBLAM/IMVP-16. Patients with life-threatening tumor progression or extension received COPBLAM/IMVP-16 initially. Treatments were chosen in accordance with tumor extension and response to prednisone. Treatment modalities were not compared. RESULTS: Twenty-eight patients received primary prednisone, 18 received secondary prednisone, and 11 received primary chemotherapy. The complete response rates (with 95% CIs) were 29% (CI, 12% to 46%), 56% (CI, 33% to 79%), and 64% (CI, 36% to 92%), respectively. The median observation time of surviving patients was 28 months (range, 7 to 53). The median overall survival time was 15 months. The probabilities (with 95% CIs) of overall survival, event-free survival, and relapse at 36 months were 40.5% (CI, 24% to 56%), 32.3% (CI, 17% to 47%), and 34.6% (CI, 14% to 56%), respectively. At the time of evaluation, 22 of 39 patients had died, 7 of noninfectious complications and 14 of infections. CONCLUSIONS: Prednisone with or without COPBLAM/IMVP-16 treatment in AILD-type lymphoma leads to complete remissions in about half of the patients and in long-term, disease-free survival for one third.

Adult↗

Multiple drug resistance gene expression in human renal cell cancer is associated with the histologic subtype.

Overexpression of p170 glycoprotein, the product of the multiple drug resistance (mdr) gene, has been associated with resistance to various cytotoxic drugs used in the treatment of human neoplasms. Normal renal epithelial cells express p170 as a function of their secretory capacity. Because renal cell carcinomas (RCC) respond poorly to chemotherapeutic regimens, p170 expression was studied in primary RCC. Such expression was measured in 40 human RCC and normal kidney tissues using immunohistochemical staining with the monoclonal antibody C-219. Staining intensities of the whole tumor and of different areas of the cryostat sections were transformed into digital numbers using an algorithm designed for this purpose. In most tumors, an inhomogeneous staining pattern and a correlation between grade of differentiation and C-219 immunoreactivity was observed. A comparison of the tumors according to their histopathologic subtypes showed clear differences. The means (range) of the staining intensities of the different types of RCC: clear cell carcinoma Grade 1 (n = 3), 2.0 (2.0 to 2.0); clear cell carcinoma Grade 2 (n = 19), 0.8 (0.0 to 2.9); clear cell carcinoma Grade 3 (n = 5), 0.1 (0.0 to 0.2); tubular carcinoma (n = 4), 2.0 (2.0 to 3.0); anaplastic carcinoma (n = 8), 0.05 (0.0 to 0.2); oncocytoma (n = 1), 0.0 (0.0 to 0.0); and normal kidney (n = 40), 0.5 (0.0 to 2.0). The differences between anaplastic, clear cell, and tubular carcinoma were significant (P less than 0.001 by Kruskal-Wallis test). In addition, the difference between the three subgroups of clear cell carcinoma was significant (P less than 0.01). It was concluded that the histopathologic subtypes of RCC correlate with the degree of mdr gene expression, as determined by staining with the C-219 monoclonal antibody.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

[The long-term toxicity of polychemotherapy in successfully treated testicular carcinoma].

Of 55 patients with testicular cancer, treated by combination chemotherapy including cisplatin, 21 (mean age 35 [21-51] years) were reexamined for late sequelae of the chemotherapy 1-9 years later. No patient had a recurrence or second malignancy. They all had normal renal function (renal sequence scintigraphy; creatinine clearance). Seven of 20 patients had a polyneuropathy, nine of 18 had high-tone hearing loss. Two patients became fathers after treatment. In nine of 20 patients the serum concentration of follicle-stimulating hormone was raised to above 20 mU/ml, evidence of germ-cell damage. Six of 13 patients had an abnormal ejaculation following retroperitoneal lymphadenectomy or excision of a residual tumour. There was no evidence of any life-limiting toxicity of the chemotherapy.

Adult↗

Incomplete functional differentiation of HL-60 leukemic cells by synthetic lipopeptides. Partial inhibition by pertussis toxin of enhanced superoxide formation.

In human neutrophils, the synthetic lipopeptide, N-palmitoyl-S-[2,3- bis(palmitoyloxy-(2RS)-propyl]-(R)-cysteinyl-(S)-seryl-(S)-lysyl-( S)-lysyl-(S) -lysyl-(S)-lysine [Pam3CysSer(Lys)4], activates NADPH-oxidase catalyzed superoxide (O2-) formation through pertussis-toxin-sensitive and pertussis-toxin-insensitive mechanisms (Seifert, R., Schultz, G., Richter-Freund, M., Metzger, J., Wiesmüller, K.-H., Jung, G., Bessler, W. G. & Hauschildt, S. (1990) Biochem. J. 267, 795-802). We studied the effects of lipopeptides on differentiation of HL-60 leukemic cells. Pam3CysSer(Lys)4 enhanced phorbol-12-myristate-13-acetate-induced O2- formation (presumably through the expression of components of NADPH oxidase) in a concentration-dependent manner with a half-maximal effect at 100 ng/ml and a maximum at 1 microgram/ml. The effect of the lipopeptide was evident after 24 h and reached a plateau after 48 h. (2S,6S)-2-Palmitoylamino-6,7- bis(palmitoyloxy)heptanoyl-(S)-seryl-(S)-lysyl-(S)-lysyl-(S) -lysyl-(S)-lysine enhanced O2- formation as well. The effects of Pam3CysSer(Lys)4 were potentiated by dibutyryl cAMP, dimethyl sulfoxide, retinoic acid, 1,25-dihydroxyvitamin D3, interferon-gamma and tumor-necrosis-factor-alpha. Pertussis toxin, but not its B-oligomer, partially inhibited enhanced O2- formation induced by Pam3CysSer(Lys)4. O2- formation induced by arachidonic acid and gamma-hexachlorocyclohexane were more sensitive to inhibition by pertussis toxin than O2- formation induced by phorbol 12-myristate 13-acetate. Enhanced O2- formation induced by dibutyryl cAMP was not affected by pertussis toxin. Unlike ATP, histamine, prostaglandin E1 and the beta-adrenergic agonist, isoproterenol, Pam3CysSer(Lys)4 did not increase cytosolic Ca2+ [( Ca2+]i) in undifferentiated HL-60 cells. Histamine but not lipopeptides stimulated high-affinity GTPase of guanine-nucleotide-binding proteins in membranes of undifferentiated HL-60 cells. In Pam3CysSer(Lys)4-differentiated HL-60 cells, the responsiveness to the [Ca2+]i-increasing agonists, N-formyl-L-methionyl-L-leucyl-L-phenylalanine, C5a and leukotriene B4, was increased, whilst the responsiveness to prostaglandin E1 and isoproterenol was decreased. Pam3CysSer(Lys)4 did not inhibit proliferation of HL-60 cells but decreased transferrin receptor expression and increased C3bi receptor expression. Pertussis toxin did not affect proliferation and expression of transferrin and C3bi receptors. Dibutyryl cAMP was considerably more effective than Pam3CysSer(Lys)4 at inducing alterations in the above parameters. Our results suggest that (a) Pam3CysSer(Lys)4 induces incomplete functional differentiation of HL-60 cells through a mechanism which does not depend on a rise in [Ca2+]i and is different from that of other differentiation-inducing substances and (b) the mechanism by which Pam3CysSer(Lys)4 induces differentiation involves pertussis-toxin-sensitive and pertussis-toxin-insensitive mechanisms.

Bucladesine↗

Treatment of neutropenia in Felty's syndrome with granulocyte-macrophage colony-stimulating factor--hematological response accompanied by pulmonary complications with lethal outcome.

We report on a 67-year-old man with Felty's syndrome (FS) complicated by recurrent pneumonia and an infected wound, which was not healing in spite of maximal antibiotic and local therapy. Encouraged by previous experience, we treated him with granulocyte-macrophage colony-stimulating factor (GM-CSF). His total leukocyte count rose, but the patient's pneumonia deteriorated. In addition, a previously known chronic obstructive lung disease (COLD) was exacerbated acutely. These complications finally led to his death. Postmortem examination revealed widespread pneumonia with invasive aspergillosis and a peripheral adenocarcinoma in his left lung.

Adenocarcinoma↗

Mobilization of circulating haemopoietic cells (blood stem cells) by GM-CSF in patients with malignancies.

Autologous reinfusion of circulating haemopoietic progenitor and stem cells (blood stem cell transplantation) has emerged as an alternative to autologous bone marrow transplantation in a variety of malignant diseases. Major obstacles associated with harvest of blood stem cells by leukapheresis are: 1. relatively high costs, and 2. discomfort caused to the patient, as generally five to ten settings of leukapheresis are necessary to harvest a number of blood stem cells sufficient for haemopoietic restitution following myeloablative therapy. GM-CSF recently has been shown to effectively increase circulating haemopoietic cells, when given subsequent to even highly-toxic therapy. This report summarizes our data on mobilization of blood stem cells by GM-CSF cells in multiple myeloma patients.

Combined Modality Therapy↗

Acute parvovirus B19 infection mimicking myelodysplastic syndrome of the bone marrow.

A 36-year-old, previously healthy woman was referred to our institution with pancytopenia and splenomegaly for suspected acute leukemia. Bone marrow aspiration showed marked dysplastic changes, excess of blasts, and only spurious red blood cell precursors. Action was taken to prepare allogeneic bone marrow transplantation from an HLA identical sibling for myelodysplastic syndrome. Repeat cytological examination of the bone marrow revealed striking hyperplasia of the red cell line with presence of abnormal giant proerythroblasts. Acute parvovirus B19 infection was suspected and confirmed by detection of anti-B19 IgM and B19 DNA. The underlying disease for this transient aplastic crisis was a formerly unknown hereditary spherocytosis.

Adult↗