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Biomedical subjects

H Matthes

Publications and source records attributed to H Matthes.

At least 19 recordsLinked to original sources
PubMed1992

Immunodetection of multiple species of retinoic acid receptor alpha: evidence for phosphorylation.

Polyclonal and monoclonal antibodies were raised against synthetic peptides (or fusion protein) corresponding to cDNA-deduced amino acid sequences unique to the human and mouse retinoic acid (RA) receptor alpha 1 (hRAR-alpha 1 and mRAR-alpha 1, respectively). Two rabbit polyclonal antibodies directed against either the F region fused to DHFR [RP alpha (F)] or the D2 region [RP alpha (D2)] were selected. Using either immunocytochemistry, Western blotting analysis, or immunoprecipitation, they were found to be specific for human and mouse RAR-alpha 1 proteins produced by COS-1 cells transiently transfected with vectors expressing the RAR-alpha 1 cDNA. Three mouse monoclonal antibodies directed against either the F region [(Ab9 alpha (F) and Ab12 alpha (F)] or the A1 region [Ab10 alpha 1(A1)] recognized transiently expressed human and mouse RAR-alpha 1 proteins, when either immunocytochemistry or immunoprecipitation was used. In addition, Ab9 alpha (F) and Ab12 alpha (F), but not Ab10 alpha 1(A1), revealed the RAR-alpha 1 proteins by Western blotting analysis. Ab9 alpha (F) was also able to "supershift" RAR-alpha 1 protein-RARE oligonucleotide probe complexes in gel retardation assays. All these antibodies recognized also the transiently expressed mRAR-alpha 2 isoform, with the exception of Ab10 alpha 1 (A1), which is specific for the A1 region of RAR-alpha 1. These antibodies have enabled us to detect the presence of mRAR-alpha as multiple species in mouse embryo and adult tissue extracts as well as in embryonal carcinoma (EC) cells. Moreover, we found that one of these species (51 kDa) was phosphorylated in EC cells. This phosphorylation was not affected by RA treatment, but appeared to be dependent on the differentiation state of the EC cells.

Amino Acid Sequence↗
PubMed1992

Cellular localization of procollagen gene transcripts in inflammatory bowel diseases.

The cellular localization of procollagen types I, III, IV, and V gene transcripts was determined in tissues from 12 patients with either Crohn's disease (CD) or ulcerative colitis (UC) and nine controls by in situ hybridization with 35S-labeled RNA probes. In CD, the signal intensity and number of labeled cells were significantly increased, particularly in deeper intestinal layers. In contrast, the labeled cells in UC were concentrated in the subepithelial intestinal layers, with an overexpression of procollagen III RNA transcripts. Immunohistological stainings for procollagen types I, III, and IV showed a weaker staining in UC than in CD, indicating that increased transcript levels in UC are unrelated to the enhanced collagen protein deposition, although the increase of procollagen messenger RNA levels correlated with the density of the inflammatory infiltrate. It was concluded that both CD and UC show highly increased procollagen RNA transcript levels but differ in collagen deposition. Thus, different posttranscriptional or posttranslational regulatory mechanisms, such as collagen degradation, may account for the observed differences.

Adult↗
PubMed1992

Increased collagen type III synthesis by fibroblasts isolated from strictures of patients with Crohn's disease.

Increased type III collagen deposition in all layers of the intestinal tract, including the lamina propria, is a common feature of strictures in Crohn's disease. In the present study, it was found that in comparison with fibroblasts from normal or nonstrictured but inflamed intestinal lamina propria, the fibroblasts isolated from strictures of patients with Crohn's disease produce significantly more collagen, especially collagen type III. Transforming growth factor beta 1 (TGF-beta 1) significantly increased collagen type III synthesis in intestinal lamina propria fibroblasts isolated from all patients. The effect of TGF-beta 1 on type III collagen synthesis in fibroblasts from strictures in Crohn's disease was significantly higher than that in fibroblasts from inflamed specimens of the same patients. In contrast, platelet-derived growth factor decreased collagen type III synthesis in lamina propria fibroblasts derived from strictures compared with fibroblasts from nonstrictured but inflamed tissue. These findings indicate that fibroblasts in the lamina propria of patients with Crohn's disease have a different reactivity towards cytokines. On the basis of increased type III collagen deposition in intestinal strictures of Crohn's disease by using cell adhesion and cell proliferation assays, it was shown that collagen type III stimulated adhesion and proliferation of lamina propria fibroblasts. The current data provide evidence that the different reactivity of mesenchymal cells to cytokines in terms of synthesizing type III collagen fibrils, which is a major component of collagen fibrils, may play an important role in the pathogenesis of fibrosis and stricture formation in chronic inflammatory bowel diseases.

Adult↗
PubMed1992

Laminin binding in membranes of a rat pancreatic acinar cell line are targets for glucocorticoids.

The adhesive properties of tumor cells to basement membranes are known to play a crucial role in the complex process of tumor invasion and metastasis. Therefore, the interaction between the rat pancreatic acinar cell line AR42J and various extracellular matrix components along the route of differentiation induced by glucocorticoids was investigated. AR42J cells displayed a significantly higher affinity to laminin than to type IV collagen and fibronectin. Flow cytometric analysis showed expression of the 67-kilodalton laminin receptor and the integrin VLA-6 as potential laminin binding proteins in AR42J cells. Cell adhesion inhibition studies revealed that binding of undifferentiated AR42J cells to laminin was mediated predominantly by the 67-kilodalton laminin receptor. Dexamethasone pretreatment, which results in a more differentiated phenotype of AR42J cells, reduced the adhesion to laminin. In contrast to undifferentiated cells, interaction of differentiated AR42J cells to laminin was mediated by VLA-6. Dexamethasone-induced differentiation of pancreatic AR42J cells was paralleled by a decreased expression of 67-kilodalton laminin receptors, most likely because of a downregulation of the steady-state concentration of 67-kilodalton laminin receptor messenger RNA induced by dexamethasone. The hormonal modulation of cell matrix interactions opens interesting perspectives to the potential regulation of infiltrative growth and metastasis in pancreatic cancer.

Animals↗
PubMed1992

Percutaneous absorption of azelaic acid in humans.

Six healthy male volunteers received a single topical treatment with 5 g of an anti-acne cream containing 20% azelaic acid (AzA) onto the face, the chest and the upper back. One week later 1 g of AzA was given orally to the same subjects as aqueous microcrystalline suspension. Following the two treatments the renal excretion of the unchanged compound was measured. Analysis included ether extraction of the urine, derivatization of extract and HPLC with UV detection. After topical application 2.2 +/- 0.7%, and after oral administration 61.2 +/- 8.8% of the dose had been excreted unchanged with the urine. By comparing both amounts, the percutaneous absorption of AzA from the cream was assessed to 3.6% of the dermally applied dose.

Absorption↗
PubMed1992

Diminished expression of integrin adhesion molecules on human colonic epithelial cells during the benign to malign tumour transformation.

Integrins are transmembrane molecules that mediate cell-cell and cell-substratum adhesion. Because alterations in the adhesive properties of tumour cells are thought to influence tumour cell invasion, the expression of integrin alpha and beta chains in 19 human colorectal carcinomas, eight adenomas, and eight normal colon tissues was examined immunohistochemically using an indirect immunofluorescent technique. Normal colonic epithelial cells were found to express the integrin alpha 3, alpha 5, alpha 6, beta 1, and beta 4 chains, whereas the alpha 2 chain was expressed only on epithelial cells lining the base of the crypts and was absent from cells lining the mouth of the crypts or the surface epithelium. No epithelial staining of the alpha 1, alpha 4, beta 2, and beta 3 chains was observed. A progressive reduction of all normally expressed alpha and beta chains was associated with increasing neoplastic transformation. The expression of the alpha 3 and alpha 5 chains was already noticeably reduced in adenomas, and was completely absent in most colonic carcinomas. In contrast, alpha 6, beta 1, and beta 4 expression was maintained in adenomas, whereas the transformation from benign to malignant neoplasms associated with infiltrative growth was characterised by diminished or lost expression of alpha 6, beta 1, and beta 4 chains. Thus, the decreased expression of integrins in human colon carcinomas may contribute to the altered adhesion and migration properties of these tumour cells.

Adenocarcinoma↗
PubMed1992

[Hemorheologic findings in hyperviscosity syndrome and their modification by plasmapheresis].

A patient suffering from refractory immunocytoma was treated with therapeutical plasmapheresis. To estimate the hemorheological risk during and at the end of the therapy, hemorheological measurements were performed. Hematocrit, aggregation index, filtration index, plasma viscosity, colloid osmotic pressure and protein concentrations were analyzed. The efficiency of the plasmapheresis treatment is demonstrated by the reduction of the plasma viscosity from 5.5 to 2.3 mPa (57% reduction) and of the filtration index from 43.9 to 29.7 (32% reduction). The colloid osmotic pressure decreased from 3.4 to 2.5 kPa (26% reduction), plasma protein concentration from 106 to 86 g/l (19% reduction) and IgM concentration from 100 to 82 g/l (18% reduction), while the albumin concentration remained constant.

Blood Viscosity↗
PubMed1992

Percutaneous absorption of methylprednisolone aceponate after single and multiple dermal application as ointment in male volunteers.

Six healthy, elderly volunteers were treated once daily with Advantan ointment containing 0.1% of methylprednisolone aceponate (MPA, CAS 86401-95-8) in an area dose of 5 mg ointment/cm2 on a marked area of 80 cm2 of intact skin on the back for 14 days. The ointments used for treatment on days 1 and 8 contained 14C-MPA with a specific radioactivity of 2.5 MBq/mg MPA. Following the radioactive pulse doses, the concentrations of 3H-radioactivity in plasma and urine were monitored up to 48 h and 7 days, respectively. The concentration of 14C-radioactivity in the plasma did not exceed the limit of detection of 0.3 ng MPA-equiv./ml. Percutaneous absorption of MPA through intact skin was small (les than 1%) and did not change during repeated application, indicating that the penetration barrier is not influenced by the drug or the vehicle.

Aged↗
PubMed1991

Cloning, expression, and transcriptional properties of the human enhancer factor TEF-1.

We describe the cDNA encoding the SV40 transcriptional enhancer factor 1 (TEF-1) and show that its translation initiates exclusively at an AUU codon in vivo. Cloned TEF-1, which is unrelated to other known transcription factors, specifically binds the SV40 GT-IIC and Sph enhansons. Cloned TEF-1 does not activate these enhansons in lymphoid MPC11 cells where they are known to be inactive, but represses the endogenous HeLa TEF-1 activity in vivo and in vitro. Repression is also observed with chimeras where the DNA-binding domain of the GAL4 activator replaces that of TEF-1, showing that repression results from interference/squelching. Such chimeras stimulate transcription in HeLa, but not in MPC11, cells in vivo and in HeLa cell extracts in vitro. However, high concentrations result in self-interference/squelching. These results strongly suggest that the trans-activation function of TEF-1 is mediated by a highly limiting, possible cell-specific, titratable transcriptional intermediary factor(s).

Amino Acid Sequence↗
PubMed1991

Human hybridomas derived from CD5+ B lymphocytes of patients with chronic lymphocytic leukemia (B-CLL) produce multi-specific natural IgM (kappa) antibodies.

Great numbers of CD5+ B lymphocytes were detected in the peripheral blood of patients with B-CLL. To study the antibody repertoire of this immune cell subpopulation on a monoclonal level, we fused the lymphocytes derived from five different donors to a highly efficient HAT-sensitive heteromyeloma line (CB-F7). A fusion frequency of up to 10(-5) allowed us to analyse hundreds of initial hybridoma lines per fusion. In all culture supernatants in three out of five fusions IgM lambda antibodies were detected, in two experiments only IgM kappa was measured, suggesting monoclonality of the primary hybridoma cell lines. The later fusions resulted in hybridomas producing multi-specific antibodies against both an autoantigen and an infectious agent: (i) dsDNA/influenza virus haemagglutinin; (ii) dsDNA/class V outer membrane protein type C from Neisseria meningitidis. However, no antibodies of the described specificity were detected in blood sera of patients, indicating a 'switch-on' of the immunoglobulin secretion capacity of malignant B cells during fusion to a myeloma partner. We discuss the results as further evidence for the natural multi-reactive antibody repertoire of CD5+ B cells.

Adult↗
PubMed1991

Pharmacokinetics and biotransformation of the anxiolytic abecarnil in healthy volunteers.

1. The pharmacokinetics of abecarnil were studied in eight healthy male volunteers using 14C-abecarnil and an h.p.l.c. method for determination of unchanged drug. 2. Abecarnil was rapidly and nearly completely absorbed after an oral dose of 10 mg; bioavailability was 40%. Plasma levels of the unchanged drug declined with a terminal half-life of 4 h. The total clearance of abecarnil was 11 ml/min per kg. 14C-Abecarnil was excreted rapidly and completely. The main route of elimination was in the faeces. 3. Abecarnil was extensively metabolized resulting in ether cleavage at position 6 with subsequent glucuronidation or sulphation and, to a minor extent, in ester cleavage.

Administration, Oral↗
PubMed1991

[Cell membrane binding components for constituents of the extracellular matrix: structural mediator of the epithelial matrix interaction in the gastrointestinal tract].

Growth, migration, differentiation and metabolic functions of the epithelium in the gastrointestinal tract are regulated by the extracellular matrix. Different cell membrane binding components including the integrins for constituents of the extracellular matrix are expressed in the epithelial cells. These cell membrane binding components may be structural mediators of cell-matrix interaction in the gastrointestinal tract. A characterization of this interaction is of great importance, not only to understand physiological processes, such as epithelial migration and differentiation, but also for the pathogenesis of healing processes (ulcer healing), immunologically mediated processes (adhesion of immunocompetent cells), and especially for tumor pathology (invasion and metastasis). Gastrointestinal diseases are characterized by alterations in the expression of cell membrane binding components for different constituents of the extracellular matrix. In chronic inflammatory bowel disease, a changed expression can be identified on epithelial cells and, in especially malignant transformation of epithelial cells resulted in a pathologic expression of cell adhesion molecules. Oncogenes may modify the expression and function of these cell membrane binding components in the course of malignant transformation. In animal models, it was possible to reduce the frequency of tumor invasion and metastasis and to achieve longer survival times by blocking the cell membrane binding components on malignant cells. An increasing understanding of the role of cell membrane binding components in the epithelium-matrix interaction will certainly also be translated in the future into new therapeutic concepts.

Cell Adhesion↗
PubMed1990

Co-evolution from yeast to mouse: cDNA cloning of the two NF-Y (CP-1/CBF) subunits.

NF-Y is a CCAAT box binding protein critical for the expression of diverse eukaryotic genes. We have purified the A and B subunits of NF-Y and, using microsequencing and PCR technology, have cloned the corresponding cDNAs. NF-YA and NF-YB show stretches of arresting sequence homology to the yeast transcriptional activators HAP2 and HAP3. Unlike their yeast counterparts, however, the two mouse subunits appear necessary and sufficient for CCAAT binding activity. We hypothesize that in the case of NF-Y, DNA binding and dimerization both rely on residues within the homology domains, which include rather suggestive 'half-finger' motifs.

Amino Acid Sequence↗
PubMed1989

Phenotype switch in acute leukemia patients after intensive chemotherapy.

According to Stass et al. the percentage of a lineage switch occurs in 6.7%-8.6% of patients with acute leukemia. Mostly, a conversion from the lymphoid to the myeloid phenotype is seen. In our three cases we found two switches from the myeloid to the lymphoid phenotype and only one from lymphoid to myeloid. This lineage switch is seen in relapsing and resistant leukemia cases. Different hypotheses have been discussed concerning the phenotype switch. Cytostatic chemotherapy may eradicate one leukemic cell clone, allowing another one to proliferate. Otherwise, the leukemic transformed stem cell could be influenced by the chemotherapy, resulting in a change of the differentiation program of the cell and following with a switch of marker expression. Perhaps there is some clinical importance to monitoring the phenotype switch in order to administer the best treatment.

Adolescent↗
PubMed1989

Single dose pharmacokinetics of gestodene in women after intravenous and oral administration.

Six healthy female volunteers (age 25 - 39 years) received 75 micrograms gestodene intravenously followed by 3 oral administrations of 25, 75 and 125 micrograms gestodene together with 30 micrograms ethinylestradiol (EE2) in a cross-over design. Gestodene plasma levels were determined using a specific RIA. After intravenous administration, plasma gestodene concentrations decayed triphasically with mean half-lives of 0.16 h, 1.5 h and 10 hours. The area under the plasma level curve, the total plasma clearance and the volume of distribution (VZ) were as follows: AUC = 35 +/- 15 ng.h/ml, CL = 0.80 +/- 0.53 ml/min/kg, and VZ = 0.66 +/- 0.43 1/kg, respectively. After oral administration of all doses, maximum plasma levels of 1.0 (25 micrograms), 3.8 (75 micrograms) and 7.0 ng/ml (125 micrograms) were achieved between 1.4 and 1.9 hours after the intake. Post-maximum levels showed 2 disposition phases with half-lives of 1 and 12 - 14 hours. Absolute bioavailabilities were calculated as 87.5 +/- 17.5% (25 micrograms), 99.3 +/- 10.9% (75 micrograms) and 110.8 +/- 17.7% (125 micrograms) indicating that gestodene is completely absorbed and systemically available at all doses investigated.

Administration, Oral↗
PubMed1989

Pharmacokinetics of 3H-cicaprost in healthy volunteers.

Cicaprost (5-[(E)-(1S,5S,6S,7R)-7-hydroxy-6-[(3S,4S)-3-hydroxy-4-methylnona- 1,6- diinyl]-bicyclo[3.3.0]octan-3-yliden]-3-oxapentanoic acid, ZK 96 480) is a novel PGI2-derivative, which is chemically stable and not subject to metabolic degradation in rats and cynomolgus monkeys. The pharmacokinetics of Cicaprost were studied in six healthy volunteers (age: 54-74 y) after i.v. infusion (2.1 micrograms over 60 min) and p.o. dosage (7.6 micrograms) of the tritiated compound. All treatments were well-tolerated by the test subjects. At the end of the infusion plasma levels of approximately 100 pg/ml were reached, declining biphasically with half-lives of 3-4 min and 64 +/- 21 min. Total clearance was 3.8 +/- 0.5 ml/min/kg. The oral dosage resulted in peak plasma levels of 251 +/- 90 pg/ml occurring at 23 +/- 5 min post dose. The terminal half-life in the plasma was 115 +/- 30 min. Gastro-intestinal absorption and absolute bioavailability of Cicaprost was complete. After both routes of administration approx. 60% of dose was excreted with the urine within 24 h, whereas fecal 3H-excretion lasted for several days and accounted for approx. 35%. Radiochromatography revealed that Cicaprost was metabolically stable in plasma and urine. In the feces several degradation products were observed apart from approx. 30% of the dose fraction being excreted unchanged by that route. The present results demonstrate that Cicaprost is an orally completely bioavailable, metabolically stable PGI2-mimetic which may be an ideal candidate for oral therapy because of its pharmacokinetic characteristics.

Administration, Oral↗
PubMed1989

Cloning of the gene encoding the yeast protein BTF1Y, which can substitute for the human TATA box-binding factor.

An activity (designated BTF1Y) in extracts of Saccharomyces cerevisiae can substitute for the human TATA box-binding factor BTF1 in a reconstituted transcription system containing the adenovirus 2 major late promoter, RNA polymerase B (II), and the basic transcription factors BTF2, BTF3, and STF. We have purified BTF1Y to homogeneity, using as assays reconstitution of in vitro transcription and DNase I footprinting on the TATA element. Both activities copurified with a 27-kDa polypeptide as determined by SDS/PAGE. Gel filtration indicated a molecular mass of 28 +/- 5 kDa under nondenaturing conditions, suggesting that the native BTF1Y protein is a monomer. BTF1Y was enzymatically cleaved, several peptides were sequenced, and appropriate oligonucleotide probes were synthesized to clone the BTF1Y gene from a yeast genomic library. The BTF1Y gene contains a 720-base-pair open reading frame encoding a protein of 27,003 Da. The recombinant protein expressed in HeLa cells exhibited the same chromatographic characteristics and in vitro transcriptional activity as BTF1Y prepared from yeast extracts, confirming the identity of the gene. Gene-disruption experiments indicated that the yeast BTF1Y gene is a single-copy essential gene.

Adenoviruses, Human↗