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H Engel

Publications and source records attributed to H Engel.

At least 37 records · Page 2Linked to original sources
PubMed2000

Genomic structure and chromosome mapping of human and mouse RAMP genes.

The cDNAs for human and murine Receptor Activity Modifying Proteins and for the associated murine Calcitonin Receptor Like Receptor were isolated. The human RAMP1 and RAMP3 genes possess two introns and human RAMP2 possesses three introns. Human RAMP1 was assigned to chromosome 2q36-->q37.1, RAMP2 to 17q12-->q21.1 and RAMP3 to 7p13-->p12. Mouse Ramp1 was assigned to chromosome 1 and Ramp2 and Ramp3 were assigned to chromosome 11.

Amino Acid Sequence↗
PubMed2000

Assignment of transcription factor NFAT5 to human chromosome 16q22.1, murine chromosome 8D and porcine chromosome 6p1.4 and comparison of the polyglutamine domains.

To date, transcription factors of the NFAT family (nuclear factors of activated T cells) have been described for mouse and man. Recently, we mapped the human NFAT5 gene to chromosome 16 by PCR using DNA from hybrid cell lines. Here we report the exact position of the human gene between D16S496 and WI5254 within the 16q22.1 subband, the localization of the murine gene at chromosome 8D, and the identification and mapping of the porcine counterpart to chromosome 6p1.4.

Animals↗
PubMed2000

Conservative treatment vs. mastectomy without radiotherapy in aged women with breast cancer--a prospective and randomized trial.

OBJECTIVE: To determine whether tumorectomy with tamoxifen in women over 70 years achieves the same treatment results as mastectomy plus tamoxifen. MATERIAL AND METHODS: Prospective randomized analysis of 121 patients over 70 with breast cancer clinically negative axilla and tumor up to 4 cm diameter. Randomization was according to even or odd birth month. Branch A: Madden operation + tamoxifen 20 mg OD (once/day). Branch B: Tumorectomy to disease free margins + tamoxifen 20 mg OD. RESULTS: Survival rate of five years for the Madden operation was 69% and for tumorectomy 71.4% with a mortality from other causes of 23.1%. Survival probability (specific death) at 5 years was of 93.4% for the Madden group and 95.2% for tumorectomy. A significant increase of the mortality was observed in those patients that had recurrences, no matter of treatment given. Specific death cause did not vary with age, but did for other causes, this being significant. CONCLUSIONS: Tumorectomy plus tamoxifen demonstrated to be as effective as Madden Op. plus tamoxifen in women over 70 years with T1-T2-N0 disease.

Aged↗
PubMed2000

Cytokine expression of T cells in chronic myeloid leukemia.

OBJECTIVE: To evaluate the function of T cells in chronic myeloid leukemia (CML). METHODS: Interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), interleukin-3 (IL-3), interleukin-4 (IL-4), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF alpha), and granulocyte macrophage-colony stimulating factor (GM-CSF) gene expressions were investigated by reverse transcription polymerase chain reaction (RT-PCR) assay in fluorescence active cell sorter (FACS) sorted peripheral blood CD2+/CD56-T cells from 12 CML patients, 10 meylodysplastic syndrome (MDS) patients and 7 normal individuals. RESULTS: TNF alpha mRNA was transcribed in T cells from all of the CML, MDS and normal individuals. IL-1 beta mRNA was transcribed in T cells from 10 CML, 9 MDS and 6 normal individuals. Low levels of IL-2 and IL-4 mRNA were detected in 5 CML patients. IL-3, IL-6 and GM-CSF mRNA were undetectable in all samples. CONCLUSION: IL-4 and IL-2 were expressed abnormally in T cells of CML.

Adult↗
PubMed1999

B cells are programmed to activate kappa and lambda for rearrangement at consecutive developmental stages.

Kappa and lambda, the two types of immunoglobulin light (L) chains present in mammals, contribute differently to the L chain pool of each species. Here we show that the extreme preponderance of kappa in the mouse results from programmed sequential activation of the kappa and lambda loci. Activation--a prerequisite of rearrangement--was monitored by analyzing transcription of unrearranged J-C clusters. Upon in vitro differentiation of a rearrangement-deficient pro/pre-B line, germ-line transcripts of the lambda J-C clusters, that are newly described here, became detectable 2 days later than their counterparts of J-C kappa. Clear differences could also be observed in vivo: germ-line transcripts of kappa were already present in large B220+ CD25+ pre B-II cells whereas germ-line lambda transcripts first became detectable at the consecutive developmental stage of small B220+ CD25+ pre-B-II cells. This activation pattern was found to be identical in mice which can not rearrange kappa due to a targeted deletion or inactivation of kappa. This suggests that pre-B-II cells follow a hit-and-run mechanism of development which includes programmed transitions and differential activation of the L chain loci, i.e. kappa first, then lambda. Thus, privileged activation of kappa might be the decisive factor in setting the 10:1 ratio of kappa to lambda present in the mouse.

Animals↗
PubMed1999

FDG PET-negative liver metastases of a malignant melanoma and FDG PET-positive hurthle cell tumor of the thyroid.

A Hurthle cell tumor (oncocytoma) of the thyroid presented as a hypermetabolic focus in a fluorodeoxyglucose positron emission tomography (FDG PET) study which was performed as staging procedure in a patient with malignant melanoma. This finding led to the initial diagnosis of a metastasis. In contrast, multiple liver metastases, seen on MRI and sonography, did not show any increased FDG uptake. Cytology results of one liver mass confirmed a melanoma metastasis, and of the neck mass, a Hurthle cell tumor. The Hurthle cell tumor was, based on clinical evidence, thought to be benign. This is the first description of a FDG PET-positive benign Hurthle cell tumor, with FDG PET-negative liver metastases of a malignant melanoma, in the same patient.

Adenoma, Oxyphilic↗
PubMed1999

Genomics of the human genes encoding four TAFII subunits of TFIID, the three subunits of TFIIA, as well as CDK8 and SURB7.

By in situ chromosomal hybridization, and by somatic cell and radiation hybrid analysis, we have determined the genomic position of the human genes encoding four TAFII subunits of TFIID (TAFII150, TAFII105, TAFII68, TAFII18), the three subunits of TFIIA (TFIIA35 and TFIIA19, both encoded by the same gene, and TFIIA12), CDK8, and SURB7. All of these proteins are bona fide components of human class II holoenzymes as well as targets of signal transduction pathways that regulate genome expression. The genes encoding them are present in the human genome in a single copy and are localized at 8q23, 18q11.2, 17q11.1-11.2, 1p21, 14q31, 15q21-23, 13q12, and 12p12, respectively. We have mapped all of them to chromosomal regions where hereditary genetic diseases have been localized or which are involved in malignancies, which makes them potential candidates for a causal involvement in these phenotypes.

Abnormalities, Multiple↗
PubMed1999

Detection of circulating tumour cells in patients with breast or ovarian cancer by molecular cytogenetics.

Detection of micrometastases in patients with solid tumours may aid the establishment of prognosis and development of new therapeutic approaches. This study was designed to investigate the presence and frequency of tumour cells in the peripheral blood (PB) of patients with breast or ovarian cancer by using a combination of magnetic activated cell sorting (MACS) and fluorescence in situ hybridization (FISH). Separated tumour cell and PB-samples from 48 patients (35 breast cancers, 12 ovarian tumours, one uterine sarcoma) were analysed for the presence of numerical aberrations of chromosomes 7, 12, 17 and 17 q11.2-q12. Twenty-five patients had primary disease and 23 had relapsed. The technique allows the detection of one tumour cell in 106 normal cells. Circulating tumour cells were detected in 35/48 cases (17 patients had relapsed and 13 primary carcinoma with lymph node or solid metastases) by the expression of anti-cytokeratin and the presence of numerical chromosomal abnormalities. PB-tumour cells of patients with a primary carcinoma and without solid metastases had a significantly lower percentage of chromosomal aberrations, especially for chromosome 12 (P = 0.035; P = 0.038) compared to those with relapsed disease and solid metastases. Detection and quantification of minimal residual disease may monitor the response to cytotoxic or hormonal therapy and may identify women at risk of relapse.

Adult↗
PubMed1999

Quantitation of minimal residual disease in acute myelogenous leukemia and myelodysplastic syndromes in complete remission by molecular cytogenetics of progenitor cells.

Detection of karyotypic clonal abnormalities are prognostically useful in patients with acute myelogenous leukemia (AML) and myelodysplastic syndromes (MDS), but cytogenetic methods are not sensitive enough to detect low numbers of residual leukemic cells in patients who have achieved complete remission (CR). Fluorescence in situ hybridization (FISH) and fluorescence activated cell sorting (FACS) were used to investigate the frequency and presence of minimal residual disease (MRD) in AML and MDS patients (n = 28) with monosomy of chromosomes 7, 17 and 18 and trisomy of chromosomes 6, 8, 9 and 10 in CR. MRD was detected in all patients with monosomy 7 (n = 10) and followed by relapse in eight patients after 4.8 +/- 3.1 months. In contrast, persistent leukemic cells occurred in 11/12 patients with trisomy 8, but only three of them relapsed after 7.7 +/- 4.0 months. Cox regression analysis showed that cytogenetic class and levels of clonal cells at CR were related to time to relapse (P = 0.001). The level of MRD identified patients at high and low risk of relapse. High absolute levels of proliferating residual leukemic cells correlated with monosomy 7 and high risk of relapse.

Acute Disease↗
PubMed1999

The phenotypic spectrum of GLI3 morphopathies includes autosomal dominant preaxial polydactyly type-IV and postaxial polydactyly type-A/B; No phenotype prediction from the position of GLI3 mutations.

Functional characterization of a gene often requires the discovery of the full spectrum of its associated phenotypes. Mutations in the human GLI3 gene have been identified in Greig cepalopolysyndactyly, Pallister-Hall syndrome (PHS), and postaxial polydactyly type-A (PAP-A). We studied the involvement of GLI3 in additional phenotypes of digital abnormalities in one family (UR003) with preaxial polydactyly type-IV (PPD-IV), three families (UR014, UR015, and UR016) with dominant PAP-A/B (with PPD-A and -B in the same family), and one family with PHS. Linkage analysis showed no recombination with GLI3-linked polymorphisms. Family UR003 had a 1-nt frameshift insertion, resulting in a truncated protein of 1,245 amino acids. A frameshift mutation due to a 1-nt deletion was found in family UR014, resulting in a truncated protein of 1,280 amino acids. Family UR015 had a nonsense mutation, R643X, and family UR016 had a missense mutation, G727R, in a highly conserved amino acid of domain 3. The patient with PHS had a nonsense mutation, E1147X. These results add two phenotypes to the phenotypic spectrum caused by GLI3 mutations: the combined PAP-A/B and PPD-IV. These mutations do not support the suggested association between the mutations in GLI3 and the resulting phenotypes. We propose that all phenotypes associated with GLI3 mutations be called "GLI3 morphopathies," since the phenotypic borders of the resulting syndromes are not well defined and there is no apparent genotype-phenotype correlation.

Amino Acid Sequence↗
PubMed1999

Fetal cord blood as an alternative source of hematopoietic progenitor cells: immunophenotype, maternal cell contamination, and ex vivo expansion.

The present study was performed to investigate the character of hematopoietic progenitor cells in fetal cord blood (CB). Thirty blood samples from fetuses at a median of 24 weeks of gestation (range 19-29) and 30 neonatal CB samples were analyzed for their immunophenotype by three-color flow cytometry and examined for the presence of female cells by fluorescence in situ hybridization (FISH). We tested the effects of different cytokine combinations (rhIL-1beta, rhIL-3, rhIL-6, rh erythropoietin [rhEPO], rhGM-CSF plus rhSCF, and rhSCF plus rhflt3-ligand) on the differentiation of 100 CD34+-enriched neonatal CB cells for up to 21 days. Ex vivo expansion of 32 unselected fetal blood samples cells was performed in the presence of rhSCF and rhflt3-ligand. The percentage of CD34+ cells in fetal blood was significantly higher compared with neonatal CB (1.24%+/-0.82% versus 0.33%+/-0.18%, p = 0.0001) and inversely correlated with the age of gestation. The contamination of fetal and neonatal CB with maternal cells was low (1.72%+/-0.89%, range 1.0%-4.0%). By using rhflt3-ligand we were able to expand committed progenitor cells while maintaining cells with stem cell function. The use of expanded fetal immature progenitors might have implications for in utero transplantation and autologous gene therapy.

Cell Culture Techniques↗
PubMed1999

Point mutations throughout the GLI3 gene cause Greig cephalopolysyndactyly syndrome.

Greig cephalopolysyndactyly syndrome, characterized by craniofacial and limb anomalies (GCPS; MIM 175700), previously has been demonstrated to be associated with translocations as well as point mutations affecting one allele of the zinc finger gene GLI3. In addition to GCPS, Pallister-Hall syndrome (PHS; MIM 146510) and post-axial polydactyly type A (PAP-A; MIM 174200), two other disorders of human development, are caused by GLI3 mutations. In order to gain more insight into the mutational spectrum associated with a single phenotype, we report here the extension of the GLI3 mutation analysis to 24 new GCPS cases. We report the identification of 15 novel mutations present in one of the patient's GLI3 alleles. The mutations map throughout the coding gene regions. The majority are truncating mutations (nine of 15) that engender prematurely terminated protein products mostly but not exclusively N-terminally to or within the central region encoding the DNA-binding domain. Two missense and two splicing mutations mapping within the zinc finger motifs presumably also interfere with DNA binding. The five mutations identified within the protein regions C-terminal to the zinc fingers putatively affect additional functional properties of GLI3. In cell transfection experiments using fusions of the DNA-binding domain of yeast GAL4 to different segments of GLI3, transactivating capacity was assigned to two adjacent independent domains (TA(1)and TA(2)) in the C-terminal third of GLI3. Since these are the only functional domains affected by three C-terminally truncating mutations, we postulate that GCPS may be due either to haploinsufficiency resulting from the complete loss of one gene copy or to functional haploinsufficiency related to compromised properties of this transcription factor such as DNA binding and transactivation.

Animals↗
PubMed1999

Interacting spiral waves in the Oregonator model of the light-sensitive Belousov-Zhabotinskii reaction.

We study the interaction of meandering spiral waves within the framework of a modified Oregonator model for the light-sensitive Belousov-Zhabotinskii medium. In this medium the local excitation threshold can be controlled by varying the intensity of incident light. At low as well as sufficiently high light intensity we find stable axis-symmetric bound states consisting of two counter-rotating spirals. At intensity values in between, spiral pairs undergo a symmetry-breaking instability, leading to one spiral suppressing and expelling the other. To avoid the instability, we consider a spiral wave interacting with its mirror image close to a plane boundary impermeable to diffusion. The drift velocity and the drift direction of those pseudobound states parallel to the boundary are strongly influenced by the light intensity.

Journal Article↗
PubMed1999

Role of lung perfusion scintigraphy in relation to chest computed tomography and pulmonary function in the evaluation of candidates for lung volume reduction surgery.

Lung perfusion scintigraphy is employed to evaluate patients with severe emphysema who are candidates for lung volume reduction surgery (LVRS). Our purpose was to investigate the role of scintigraphy in relation to chest computed tomography (CT) and lung function in this setting. Six observers blinded to clinical data retrospectively scored preoperative scintigrams of 70 patients undergoing bilateral video-assisted LVRS according to the distribution of lung perfusion as homogeneous, intermediately heterogeneous, or markedly heterogeneous. Heterogeneity of emphysema distribution was also assessed by chest CT. Dyspnea and pulmonary function were measured preoperatively and 3 mo postoperatively. In 42 patients with markedly heterogeneous, in 18 with intermediately heterogeneous, and in 10 with homogeneous perfusion, mean (+/- SE) FEV1 increased by 57 +/- 8% (p < 0.0001), 38 +/- 9% (p < 0.001), and 23 +/- 9% (p = NS) (p = NS for intergroup comparisons). In a multiple regression analysis, functional improvement after LVRS was more closely correlated with preoperative hyperinflation and the degree of emphysema heterogeneity estimated by chest CT than with the degree of perfusion heterogeneity assessed by scintigraphy. In 16 of 22 patients with homogeneous emphysema distribution in the chest CT scintigraphy revealed intermediately or markedly heterogeneous perfusion. We conclude that lung perfusion scintigraphy has a limited role in prediction of outcome, but it may help to identify target areas for resection in LVRS candidates with homogeneous CT morphology.

Adult↗
PubMed1999

Optimization of apolipoprotein(a) genotyping with pulsed field gel electrophoresis.

BACKGROUND: Increased lipoprotein(a) is a risk factor for atherosclerosis, and its concentration in serum is inversely correlated with the size of the apoliprotein(a) [apo(a)] component. The size of the apo(a) gene is determined mainly by the Kringle IV size polymorphism. We have optimized and characterized pulsed field gel electrophoresis (PFGE) for apo(a) genotyping. METHODS: Established PFGE protocols were adjusted. The changes included the following: (a) increased DNA yields by the use of all leukocytes for isolation from either 3 mL of fresh EDTA whole blood or 250 microL of frozen buffy coats; (b) increased efficiency of Kpn1 digestion by the inclusion of a digestion buffer wash; (c) reduction of assay time by the use of capillary blotting; (d) increased sensitivity by the use of four digoxigenin-labeled apo(a) probes; and (e) identification using a single film by the inclusion of a digoxigenin-labeled lambda marker probe in addition to apo(a) probes in the hybridization mix. RESULTS: In older Caucasians, 93% (buffy coats, n=468) were heterozygous for apo(a) gene size. An inverse correlation between serum lipoprotein(a) and the sum of Kringle IV alleles was found (y = -23x + 1553; r = -0.442; n = 468). Gel-to-gel variation was minimal (3%). Imprecision (SD) was one Kringle IV repeat (control sample containing eight fragments of 72-233 kb; n=34 electrophoretic runs). CONCLUSIONS: The practicality and sensitivity of the apo(a) genotyping technique by PFGE were improved, and accuracy and reproducibility were preserved. The optimized procedure is promising for apo(a) genotyping on frozen buffy coats from large epidemiological studies.

Alleles↗
PubMed1998

Partial gene structure and assignment to chromosome 2q37 of the human inwardly rectifying K+ channel (Kir7.1) gene (KCNJ13).

The novel weakly inward rectifying potassium channel Kir7.1 is a low-conductance channel that is predominantly expressed in epithelial cells. Here we describe a partial genomic characterization and the chromosomal assignment of the human Kir7.1 gene (KCNJ13). Analysis of the genomic structure using a PCR-based approach revealed a single 2088-bp intron in the coding region of KCNJ13. PCR analysis of monochromosomal and radiation hybrid panels assigns KCNJ13 to band 2q37 between markers D2S331 and D2S345. In addition, a single nucleotide polymorphism (C524-->T), leading to an exchange of a Thr with an Ile residue at amino acid position 175, was found.

Amino Acid Sequence↗