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H Christiansen

Publications and source records attributed to H Christiansen.

At least 19 recordsLinked to original sources
PubMed1996

A novel type of DNA-binding protein interacts with a conserved sequence in an early nodulin ENOD12 promoter.

The pea genes PsENOD12A and PsENOD12B are expressed in the root hairs shortly after infection with the nitrogen-fixing bacterium Rhizobium leguminosarum bv. viciae or after application of purified Nod factors. A 199 bp promoter fragment of the PsENOD12B gene contains sufficient information for Nod factor-induced tissue-specific expression. We have isolated a Vicia sativa cDNA encoding a 1641 amino acid protein, ENBP1, that interacts with the 199 bp ENOD12 promoter. Two different DNA-binding domains were identified in ENBP1. A domain containing six AT-hooks interacts specifically with an AT-rich sequence located between positions -95 and -77 in the PsENOD12B promoter. A second domain in ENBP1 is a cysteine-rich region that binds to the ENOD12 promoter in a sequence non-specific but metal-dependent way. ENBP1 is expressed in the same cell types as ENOD12. However, additional expression is observed in the nodule parenchyma and meristem. The presence of three small overlapping ORFs in the 5'-untranslated region of the ENBP1 cDNA indicates that ENBP1 expression might be regulated at the translational level. The interaction of ENBP1 with a conserved AT-rich element within the ENOD12 promoter and the presence of the ENBP1 transcript in cells expressing ENOD12 strongly suggest that ENBP1 is a transcription factor involved in the regulation of ENOD12. Finally, the C-terminal region of ENBP1 shows strong homology to a protein from rat that is specifically expressed in testis tissue.

Amino Acid Sequence↗
PubMed1996

[Synopsis of unbalanced chromosome aberrations in neuroblastoma by comparative genomic hybridization].

Neuroblastoma is the most frequent extracranial solid tumor of early childhood. Histologically and genetically, neuroblastoma represents a heterogeneous group of tumors with significant differences in clinical behavior. In the past, several different characteristic chromosomal aberrations of neuroblastoma have been described, of which a deletion on chromosome 1p and N-myc amplification have been shown to be of major prognostic significance. However, the role of various other nonrandom DNA imbalances in tumor development and progression needs to be clarified. Taking advantage of the recently established comparative genomic hybridization (CGH), we show that this method is able to accurately detect chromosomal imbalances of known prognostic impact. As CGH gives a comprehensive picture of genetic imbalances in just one experiment, it additionally sheds light on other abnormalities of possible prognostic relevance. We therefore recommend further use of this method not only in the field of research but also for the purpose of genetic routine diagnostics in neuroblastoma.

Child↗
PubMed1996

The recurrence patterns of stages I, II and III neuroblastoma: experience with 77 relapsing patients.

BACKGROUND: Recurrences of neuroblastoma Evans' stage I-III are infrequent events and the types of its progression have rarely been reported. Therefore, we investigated the patterns of progression in a large series of patients with long follow-up. PATIENTS AND METHODS: The sites of relapse and time to progression and death of 381 consecutive patients in three cooperative trials (NB 79, 82, 85) with follow-up of 5-16 years were analysed. The Southern blot technique was used for N-myc investigation of tumor tissue. RESULTS: Of the 77 relapsing patients, 41 (53%) had local and 36 (47%) systemic recurrences. The relapses occurred in 9 of 76 stage I patients (6 local/3 systemic), in 4 of 82 stage II (1 local/3 systemic) and 64 of 223 stage III neuroblastoma (34 local/30 systemic) patients. The main sites of distant metastasis were bone marrow (41%), lymph nodes (39%) and bone (37%). The median transition time from localised to metastatic neuroblastoma was 13 months and the outcome as poor (overall survival 9 +/- 5%) as that of the primary metastatic disease (14 +/- 3%). Fifty-three children died of tumor progression and 15 patients of treatment-related complications or other non-tumor conditions. The median age at diagnosis was 43 months for the group with systemic relapse compared to 19 months with only local and 10 months without recurrences (p < 0.001). Elevated serum LDH levels at first diagnosis were seen in 81% with metastatic, in 55% with local and in 33% with no tumor progression (p < 0.001). N-myc amplification was found in 4/14 with local and in 6/12 with metastatic recurrences. CONCLUSION: The high incidence of systemic relapse and the long transition time suggest that transition from localised to metastatic neuroblastoma is not an uncommon pathway.

Adolescent↗
PubMed1996

Does expression of different EWS chimeric transcripts define clinically distinct risk groups of Ewing tumor patients?

PURPOSE: Because of the high heterogeneity of EWS gene fusions with FLI1 and ERG genes due to variable chromosomal breakpoint locations in Ewing tumors (ET) (14 different chimeric transcripts identified so far), we evaluated the clinical impact of the expression of diverse fusion transcripts in ET patients. PATIENTS AND METHODS: In a European multicenter study, 147 ET were analyzed by reverse-transcriptase polymerase chain reaction (RT-PCR) and the molecular data statistically compared with all clinical data available. RESULTS: Most tumors expressed chimeric transcripts with fusion of EWS exon 7 to FLI1 exon 6 (75 of 147) (type I) or five (39 of 147) and EWS exon 10 to FLI1 exon 5 (eight of 147) or 6 (five of 147). In five cases, chimerism between EWS exon 9 and FLI1 exons 4 and EWS exon 7 and FLI1 exon 7 or 8 was observed. Fifteen cases of EWS-ERG rearrangement were identified. In 85 of these patients treated in the European Cooperative Ewing Sarcoma Studies, molecular results were analyzed in comparison to age, sex, tumor localization, tumor volume, and disease extension. No significant correlation between the various fusion types and these features were observed. Relapse-free survival (RFS) for the 31 patients with localized disease and fusion type I tended to be longer compared with the 24 patients with localized tumors bearing other chimeric transcripts (P = .04). CONCLUSION: Results suggest a possible advantage in PFS for patients with localized disease and fusion type I transcripts, although this will require prospective validation with a larger number of patients and longer follow-up periods.

Adolescent↗
PubMed1995

Effects of glucose, tetrapyrroles and protein kinase C activators on cell proliferation in cultures of Saccharomyces cerevisiae.

Saccharomyces cerevisiae was inoculated into a yeast nitrogen base with either glycerol or glucose as carbon source. Cell proliferation was followed by colony counts on agar medium. Cells in the glycerol-supplemented medium divided less than once in 10 days. When glucose, 6-deoxy-glucose or protoporphyrin IX was added, the cells had doubling times of about 24 h and increased in number to about 0.5 x 10(6) cells ml-1. Addition of either of the protein kinase C activators oleoyl-acetyl-glycerol or phorbol-12-myristate-13-acetate did not activate cell proliferation in the glycerol medium. However, when (i) glucose was combined with either protoporphyrin IX or chlorophyllin, or (ii) either protoporphyrin IX or chlorophyllin was combined with either of the protein kinase C activators, the cells had doubling times of about 12 h. Hence, (i) glucose can act as both a carbon source and a signalling molecule for proliferation, and (ii) two systems are involved in activating cell proliferation in S. cerevisiae: one operating through a protein kinase C system and another through a guanylate cyclase system.

Cell Division↗
PubMed1995

A 200 bp region of the pea ENOD12 promoter is sufficient for nodule-specific and nod factor induced expression.

ENOD12 is one of the first nodulin genes expressed upon inoculation with Rhizobium and also purified Nod factors are able to induce ENOD12 expression. The ENOD12 gene family in pea (Pisum sativum) has two members. A cDNA clone representing PsENOD12A [26] and a PsENOD12B genomic clone [7] have been previously described. The isolation and characterization of a PsENOD12A genomic clone is presented in this paper. By using a Vicia hirsuta-Agrobacterium rhizogenes transformation system it is shown that both genes have a similar expression pattern in transgenic V. hirsuta root nodules. Promoter analyses of both PsENOD12 promoters showed that the 200 bp immediately upstream of the transcription start are sufficient to direct nodule-specific and Nod factor-induced gene expression.

Base Sequence↗
PubMed1995

Comparison of DNA aneuploidy, chromosome 1 abnormalities, MYCN amplification and CD44 expression as prognostic factors in neuroblastoma.

A comparison of the prognostic impact of five molecular variables in a large series was made, including tests of their nonrandom association and multivariate analysis. Molecular data were available for 377 patients and MYCN amplification, cytogenetic chromosome 1p deletion, loss of chromosome 1p heterozygosity, DNA ploidy and CD44 expression were investigated. Their interdependence and influence on event-free survival was tested uni- and multivariately using Pearson's chi 2-test, Kaplan-Meier estimates, log rank tests and the Cox's regression model. MYCN amplification was present in 18% (58/322) of cases and predicted poorer prognosis in localised (P < 0.001), metastatic (P = 0.002) and even 4S (P = 0.040) disease. CD44 expression was found in 86% (127/148) of cases, and was a marker for favourable outcome in patients with neuroblastoma stages 1-3 (P = 0.003) and 4 (P = 0.017). Chromosome 1p deletion was cytogenetically detected in 51% (28/55), and indicated reduced event-free survival in localised neuroblastoma (P = 0.020). DNA ploidy and loss of heterozygosity on chromosome 1p were of less prognostic value. Most factors of prognostic significance were associated with each other. By multivariate analysis, MYCN was selected as the only relevant factor. Risk estimation of high discriminating power is, therefore, possible for patients with localised and metastatic neuroblastoma using stage and MYCN.

Aneuploidy↗
PubMed1995

Differentiation and prognosis of neuroblastoma in correlation to the expression of CD44s.

Cell-cell and cell-extracellular matrix interactions mediated by cell adhesion molecules (for example CD44) play an important role in the cascade of metastasis and the progression of human malignant tumours. The most important aim of this review was, on the basis of our results and the literature, to show the correlation between the expression of CD44s and differentiation and prognosis of neuroblastoma. Surprisingly and in contrast to most other malignant tumours, neuroblastomas exhibited an inverse correlation between CD44s expression and tumour progression. It can be stated that CD44s is a prognostic marker in neuroblastoma which correlates significantly with the grade of tumour cell differentiation, but not with clinical stage. Moreover, there exists a statistically significant correlation between MYCN oncogene amplification and the lack of CD44s expression.

Antigens, Neoplasm↗
PubMed1995

Porcine VEG proteins and tear prealbumins.

Small soluble proteins, belonging to the lipocalin family are secreted in large amounts by tongue von Ebner's glands and lachrymal glands. In humans, the lingual protein, called VEG, and the lachrymal protein, called tear prealbumin, have shown identical cDNA sequences. In the pig, we have purified homodimeric proteins with subunits of 17 kDa, both from von Ebner's glands and from lachrymal glands. In both cases, the proteins can be resolved into two isoforms on a chromatofocusing column. Partial aminoacid sequences and full cDNA sequences have been obtained for the more abundant forms purified from both tissues. The two proteins appear to be identical, as in humans. The reason why the same protein is expressed in different tissues, as well as its physiological function, still remain to be clarified.

Amino Acid Sequence↗
PubMed1994

[Patient-related color preference and color design in the hospital].

Colour-physiological studies involving volunteers and colour-psychological interviewing of patients with varied diagnoses revealed that, currently, no compelling scientific reasons can be given for coloration in the hospital. Interviewing 68 patients from a number of clinics on the coloration of sick-rooms yielded the following preferred colours, irrespective of the patients' classing into groups by various criteria: Light colours were consistently preferred for all objects such as ceiling, walls, floor, curtains, furniture, and bed linen. It should be emphasized that even white was a desirable colour for ceilings and bed linen. Beige was found to rank first for walls, floors, curtains, and furniture, whereas the colours of wood and grey shared the second rank for floors and furniture. Green and pink ranked second for bed linen. White and green ranked second for walls and curtains, respectively. In view of the heterogeneity, the findings may not be converted into an absolute just as the recommendations by other workers. Still, the patients' wish should be given priority over decreed recommendations by experts when basic considerations of illumination (reflectance!) are allowed for in the particular overall colour design project.

Color↗
PubMed1994

Loss of the putative tumor suppressor-gene locus 1p36 as investigated by a PCR-assay and N-myc amplification in 48 neuroblastomas: results of the German Neuroblastoma Study Group.

48 primary neuroblastomas have been examined for an amplified N-myc and loss of the putative tumor suppressor-gene locus 1p36 by loss of heterozygosity studies (LOH 1p36). In 25% of these tumors N-myc amplification and/or a LOH 1p36 was detected, and these patients had a bad prognostic clinical outcome. 75% of the tumors neither had an amplified N-myc nor a LOH 1p36, and these patients had a much better prognosis. Thus, tumor genetic changes can subdivide two types of neuroblastoma with profound different clinical behavior. Detection of these genetic changes at diagnosis could help in front-line risk adapted therapy stratifications in neuroblastoma.

Base Sequence↗
PubMed1992

Clinical impact of chromosome 1 aberrations in neuroblastoma: a metaphase and interphase cytogenetic study.

Neuroblastoma tumors are characterized by aberrations of chromosome 1. Rapid detection of these chromosomal aberrations at diagnosis could give important clues to outcome and therapy. We attempted to detect numerical and structural aberrations of chromosome 1 not only by classical metaphase cytogenetics but also by interphase cytogenetics in order to overcome difficulties of karyotyping due to diminished metaphase quality and quantity in primary neuroblastoma samples. Karyotypic changes of chromosome 1 in 53 primary neuroblastomas were evaluated. In addition, we successfully performed interphase cytogenetics using single and double in situ hybridization procedures with chromosome 1-specific repetitive DNA probes on nuclei preparations obtained from 46 and 20 tumors, respectively. Polysomies of structurally normal chromosomes 1 were predominantly seen in tumors with good prognosis, whereas deletions of 1p material were nearly exclusively confined to progressive tumors. Numerical and structural chromosome 1 aberrations as studied by metaphase and interphase cytogenetics are thus valuable prognostic markers in neuroblastoma.

Chromosome Deletion↗
PubMed1992

Translocation (5;22) in an Askin's tumor.

A boy with a brain metastasis of an Askin's tumor was investigated. Cytogenetic studies revealed a near-diploid karyotype with monosomies of chromosomes 5 and 22 in the presence of a derivative chromosome der(5)t(5;22)(q35;q11). In particular, no involvement of chromosome 11 was seen.

Brain Neoplasms↗
PubMed1990

Possible role for salivary gland protein in taste reception indicated by homology to lipophilic-ligand carrier proteins.

Sensory transduction in taste and olfaction, the principal chemical senses, seems to be mediated by membrane-associated proteins on the apical surfaces of the respective receptor cells. The recent isolation and characterization of soluble 'odorant-binding proteins' secreted from the nasal glands of rat, cow and frog, led to the hypothesis that these proteins function as necessary cofactors in olfactory transduction by concentrating and delivering odorants to the receptors. The primary reception of taste stimuli occurs in specialized neuroepithelial receptor cells bundled in taste buds that are clustered in various types of papillae in the lingual epithelium of the tongue. Small tubulo-alveolar salivary glands, the von Ebner's glands, are located beneath the circumvallate and the foliate papillae. Their ducts open exclusively into the trough at the base of the papillae. Taste buds located in the medial and lateral walls of the papillae open with their taste pores into the trough and consequently are in direct contact with the secretions of von Ebner's glands. Here we report the molecular cloning and characterization of a protein of relative molecular mass 18,000 that is highly expressed in von Ebner's glands. Like the odorant-binding proteins, this protein shows similarity to members of a protein superfamily of hydrophobic molecule transporters, indicating that pre-receptor events could also be necessary for the concentration and delivery of sapid molecules in the gustatory system, and emphasizing the close relationship of taste and olfaction.

Amino Acid Sequence↗