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E Seifert

Publications and source records attributed to E Seifert.

At least 73 records · Page 4Linked to original sources
PubMed1991

[Risks of a cartilage-bone bank with reference to HIV infection].

Allogenic transplants have an established place in reconstructive procedures. For years it has been suspected that lyophilized dura mater can transmit Creutzfeld-Jakob disease. HIV infection with fully manifest AIDS and a mortality of up to 100% is now also increasing in significance. It is necessary to assess the risk of transferring HIV with allogenic transplants because HIV passes into the cell via specific surface receptors and is integrated within the chromosome. Experimental data on disinfection and sterilization of allogenic transplants stored within chromosomes and their inactivation are not available. Allogenic transplants are only used in operations for life-threatening disease. As a rule, these are elective operations which must meet the highest safety standards, also with regard to the danger of infection. Collaboration with a transplantation team is essential.

Bone Transplantation↗
PubMed1990

Gradients of Krüppel and knirps gene products direct pair-rule gene stripe patterning in the posterior region of the Drosophila embryo.

Abdominal segmentation of the Drosophila embryo requires the activities of the gap genes Krüppel (Kr), knirps (kni), and tailless (tll). They control the expression of the pair-rule gene hairy (h) by activating or repressing independent cis-acting units that generate individual stripes. Kr activates stripe 5 and represses stripe 6, kni activates stripe 6 and represses stripe 7, and tll activates stripe 7. Kr and kni proteins bind strongly to h control units that generate stripes in areas of low concentration of the respective gap gene products and weakly to those that generate stripes in areas of high gap gene expression. These results indicate that Kr and kni proteins form overlapping concentration gradients that generate the periodic pair-rule expression pattern.

Animals↗
PubMed1990

cis-acting control elements for Krüppel expression in the Drosophila embryo.

Krüppel (Kr), a gap gene of Drosophila, shows complex spatial patterns of expression during the different stages of embryogenesis. In order to identify cis-acting sequences required for normal Kr gene expression, we analysed the expression patterns of fusion gene constructs in transgenic embryos. In these constructs, bacterial lacZ expression was placed under the control of Kr sequences in front of a basal promoter. We identified cis-acting Kr control units which drive beta-galactosidase expression in 10 known locations of Kr expression in early and late embryos. More than one cis-regulatory element drives the expression in the anterior domain at the blastoderm stage, in the nervous system, the midline precursor cells and in the amino-serosa. In addition, two cis-acting elements direct the first zygotic expression of Kr in a striped subpattern within the central region of the blastoderm embryo. Both elements respond to alterations in the activities of maternal organizer genes known to be required for Kr expression in establishing the thoracic and anterior abdominal segments in the wild-type embryo.

Animals↗
PubMed1990

Regulatory elements controlling expression of the Drosophila homeotic gene fork head.

The region-specific homeotic gene fork head (fkh) is expressed and required in a variety of tissues of the developing Drosophila embryo. In order to identify the cis regulatory elements directing the complex spatio-temporal expression pattern of fkh, we have studied the subpatterns directed by defined fragments of fkh genomic DNA. These experiments enabled us to distinguish separate regulatory elements specific for the different expression domains of fkh. In addition, our analysis revealed several unexpected features such as the redundancy of regulatory elements and the overlap of regulatory elements with the transcribed regions of other genes. Moreover, the separation of normally contiguous elements effecting expression in the posterior terminal fkh domain appears to lead to novel expression domains which do not correspond to known developmental units in the embryo.

Alleles↗
PubMed1990

[Reduction of reactivity to allergic rhinitis with intravenous administration of calcium. Clinical-experimental study on the effect of changes of local airway resistance after nasal allergen provocation].

The antiallergic activity of calcium was investigated in 25 patients with allergic rhinitis by nasal provocation with increasing doses of phleum pratense during a symptom free interval. Prior to that provocation, the patients received 9 mmol calcium (Calcium-Sandoz) i.v. or placebo respectively (double blind cross-over design). The concentration of serum calcium increased after calcium injection by 0.45 +/- 0.055 mmol/l. Calcium exerted a significant protective effect as compared to placebo: higher allergen doses, (p = 0.021) i.e. 20433 biological units/ml vs. 7494 biological units/ml, were required in order to induce a defined allergic reaction (50% decrease of nasal air flow). The data thus furnish evidence that intravenous calcium reduces the allergic response in type I allergy.

Adult↗
PubMed1989

Krüppel requirement for knirps enhancement reflects overlapping gap gene activities in the Drosophila embryo.

Segmental pattern formation in Drosophila proceeds in a hierarchical manner whereby the embryo is stepwise divided into progressively finer regions until it reaches its final metameric form. Maternal genes initiate this process by imparting on the egg a distinct antero-posterior polarity and by directing from the two polar centres the activities of the zygotic genes. The anterior system is strictly dependent on the product of the maternal gene bicoid (bcd), without which all pattern elements in the anterior region of the embryo fail to develop. The posterior system seems to lack such a morphogen. Rather, the known posterior maternal determinants simply define the boundaries within which abdominal segmentation can occur, and the process that actively generates the abdominal body pattern may be entirely due to the interactions between the zygotic genes. The most likely candidates among the zygotic genes that could fulfil the role of initiating the posterior pattern-forming process are the gap genes, as they are the first segmentation genes to be expressed in the embryo. Here we describe the interactions between the gap genes Krüppel (Kr), knirps (kni) and tailless (tll). We show that kni expression is repressed by tll activity, whereas it is directly enhanced by Kr activity. Thus, Kr activity is present throughout the domain of kni expression and forms a long-range protein gradient, which in combination with kni activity is required for abdominal segmentation of the embryo.

Animals↗
PubMed1989

The homeotic gene fork head encodes a nuclear protein and is expressed in the terminal regions of the Drosophila embryo.

The region-specific homeotic gene fork head (fkh) promotes terminal as opposed to segmental development in the Drosophila embryo. We have cloned the fkh region by chromosomal walking. P element-mediated germ-line transformation and sequence comparison of wild-type and mutant alleles identify the fkh gene within the cloned region. fkh is expressed in the early embryo in the two terminal domains that are homeotically transformed in fkh mutant embryos. The nuclear localization of the fkh protein suggests that fkh regulates the transcription of other, subordinate, genes. The fkh gene product, however, does not contain a known protein motif, such as the homeodomain or the zinc fingers, nor is it similar in sequence to any other known protein.

Alleles↗
PubMed1989

[Pattern formation in Drosophila].

Drosophila proved an excellent system to study molecular processes in establishing the body pattern of an embryo. Genes which are active during oogenesis provide localized cues which regulate a cascade of zygotic genes that determines the developmental fate of the blastoderm cells along the longitudinal axis of the embryo.

Animals↗
PubMed1989

[Assessment of the quality of life of patients with incurable head-neck tumors].

Assessment of the quality of life is an additional, perhaps crucial criterion for deciding on the choice of a palliative therapy. Therefore it is necessary to know what "quality of life" means to the individual patient. We developed a questionnaire in cooperation with patients suffering from cancer of head and neck. With this questionnaire it is possible to judge how the patient rates his own quality of life. The questionnaire helps the physician to develop a palliative therapy schedule taking the psyosocial background into consideration. It improves the practicability of prospective studies concerning palliative therapy schedules.

Activities of Daily Living↗
PubMed1989

[Quo vadis endoscopic sphincterotomy?].

The results of a study from 25 centers (= Series I: 1974-1980) covering 9041 endoscopic sphincterotomies (EST) were compared with those of a second study from 20 centers (= Series II: 1981-1986) covering 10177 cases. A change was seen in the indications during the past 5 years: While choledocholithiasis after cholecystectomy remained the main indication, EST is performed with increasing frequency in patients with common bile duct stones having their gallbladder in situ as a definitive method with low complications (only 0.61% emergency cholecystectomies): Circumscript papillary stenosis became quite a rare indication. The success rate of EST because of choledocholithiasis was not improved in spite of new techniques (stone-free common bile ducts in I: 84.06%, in II: 83.97%). The complication rate decreased from 7.55% to 5.04%. Types of complications did not change. Only perforations decreased, the rates of bleeding, cholangitis and pancreatitis remained the same. The mortality diminished from 1.12% to 0.60% (the figures remained twice as high in papillary stenosis than in choledocholithiasis). There was no change in the results of EST during the past 5 years. Follow-up studies using radiological methods show worse results (recurrent stones in II: 21.2%, in I: 5.8%, stenosis of EST in II: 6.1%, in I: 3.1%): Late results of EST because of papillary stenosis are still worse compared to those of choledocholithiasis. Therefore, in spite of increasing experience and introduction of new techniques the method became safer, but the therapeutic results did not appreciably improve.

Ampulla of Vater↗
PubMed1989

[Endoscopic biopsy diagnosis of malignant lymphoma of the stomach and early stomach lymphoma].

From 1978 to 1988 a malignant lymphoma of the stomach was diagnosed endoscopic-bioptically in 47 patients. In 41 patients it was a primary gastric lymphoma, in 6 a generalized lymphoma. In 20 cases an advanced gastric lymphoma was present which was diagnosed endoscopic-bioptically without problems. In 27 cases, however, lymphomas showed polymorphous lesions which did not look tumorous. In such cases the lymphomas were found in an early stage and bioptic verification was difficult. On an average three bioptic series were needed for histological proof. In 16 lymphomas of this group the malignant infiltration was limited to mucosa/submucosa on operative resection specimens ("early gastric lymphomas") The endoscopic appearance of these early lymphomas was: thickening mucosa-folds (2 cases), extended areas of "regenerative mucosa" and granular pattern (6 cases), mainly multiple irregular ulcerations (8 cases). The above mentioned endoscopic findings are strongly suspected for an early gastric lymphoma and should be clarified by, if needed repeated, bioptic series.

Adult↗
PubMed1988

Abdominal segmentation of the Drosophila embryo requires a hormone receptor-like protein encoded by the gap gene knirps.

The body pattern along the anterior-posterior axis of the insect embryo is thought to be established by two organizing centres localized at the ends of the egg. Genetic analysis of the polarity-organizing centres in Drosophila has identified three distinct classes of maternal effect genes that organize the anterior, posterior and terminal pattern elements of the embryo. The factors provided by these gene classes specify the patterns of expression of the segmentation genes at defined positions along the longitudinal axis of the embryo. The system responsible for organizing the posterior segment pattern is a group of at least seven maternal genes and the zygotic gap gene knirps (kni). Their mutant phenotype has adjacent segments in the abdominal region of the embryo deleted. Genetic analysis and cytoplasmic transplantation experiments suggested that these maternal genes are required to generate a 'posterior activity' that is thought to activate the expression of kni (reviewed in ref. 2). The molecular nature of the members of the posterior group is still unknown. Here we report the molecular characterization of the kni gene that codes for a member of the steroid/thyroid receptor superfamily of proteins which in vertebrates act as ligand-dependent DNA-binding transcription regulators.

Abdomen↗
PubMed1988

Molecular characterization of spalt, a homeotic gene required for head and tail development in the Drosophila embryo.

The isolation, identification and structure of the spalt gene is described. This novel homeotic gene of Drosophila is required for the establishment of the posterior-most head and the anterior-most tail segments of the embryo. It encodes a small mRNA of 0.8 kb which is under the control of over 15 kb of upstream sequences as indicated by the phenotype of transformed embryos. The putative spalt protein contains internal repeats and other interesting structural motifs but no homeo box. The spalt transcript accumulates motifs but no homeo box. The spalt transcript accumulates to high levels in the segmental anlagen affected in mutant embryos but is also found in regions of the embryo where no functional requirement has been demonstrated.

Journal Article↗
PubMed1988

Differential regulation of the two transcripts from the Drosophila gap segmentation gene hunchback.

The Drosophila gap gene hunchback (hb) is required for the establishment of the anterior segment pattern of the embryo, and also for a small region of the posterior segment pattern. The hb gene encodes two transcripts from two promoters which show a differential regulation, although they code for the same protein product. The 3.2-kb transcript is expressed during oogenesis and forms an anterior-posterior gradient during the early stages of development. The first zygotic expression of hb during cleavage stages 11-12 is due to the 2.9-kb transcript. Its expression is under the control of the anterior pattern organizer gene bicoid (bcd) and it appears to be necessary and sufficient for the anterior segmentation. The 3.2-kb transcript is expressed again at syncytial blastoderm stage in the anterior yolk nuclei, as well as in an anterior stripe which is posteriorly adjacent to the domain of the 2.9-kb transcript, and as a posterior stripe. Using hb-promoter/lacZ fusion gene constructs in combination with germ line transformation, we have delimited a regulatory region for the 2.9-kb transcript to approximately 300 bp upstream of the site of transcription initiation and show that this region is sufficient to confer the full regulation by bcd.

Animals↗
PubMed1988

Long-term follow-up after endoscopic sphincterotomy (EST).

Long-term results after endoscopic sphincterotomy (EST) revealed disappearance or improvement of symptoms in 92.0%. The symptoms remained unchanged in 6.2% and deteriorated in only 1.8%. X-ray follow-up studies showed concrement-free bile ducts in 85.2%, recurrent stones in 11.3%, and a stenosis of EST in 3.5%. Satisfactory long-term results depend on the indication for EST. The results of EST for choledocholithiasis are much better than for papillary stenosis (symptom-free or improved = 91.7%: 83.7%, unchanged = 6.4%: 14.3%, deteriorated = 1.9%: 2.0%). An EST-related stenosis was more than five times more frequent (16.8%: 2.9%) in papillary stenosis than choledocholithiasis. A gallbladder in situ does not seem to be an additional risk factor after EST. Subsequent cholecystectomy was performed in only 16.2% (routinely and elective), and in only 2.0% as an emergency procedure. In approximately 50% of the cases aerobilia and reflux, and in about 100% bacteriocholia, are observed after EST. When the free outflow of bile is ensured, it is not probable that late secondary diseases will develop.

Bacterial Infections↗
PubMed1988

[The prognosis of carcinoid tumors of the stomach].

Follow-up examinations were carried out in 55 patients with small carcinoid tumours in the stomach (diameter 0.5-1.7 cm). For the most part, the tumours were located within the body and fundus of the stomach, with only 3 being found in the antrum. Thirty-five of the 55 patients (63.6%) had multiple gastric carcinoids, while in 46 patients (83.6%) concomitant chronic atrophic gastritis was also present. Eight patients were treated surgically, while 47 patients were merely kept under endoscopic/bioptic surveillance. In 34 out of 40 patients in whom the diagnosis had been established more than 6 months previously (longest observation period 13 years), follow-up findings were available (7 surgical patients, 27 non-operated patients). The patients submitted to surgery (average follow-up period 3.5 years) are alive and free of complaints between 1 and 9 years post-op; no metastases have occurred, but a recurrent tumour has developed in a single patient. Among the 27 non-operated patients (average follow-up period 3.6 years), 3 have died of diseases unrelated to the carcinoid tumours, in none of the other patients has there been any change in the findings. On the basis of these results it is concluded that, in carcinoid tumours of the stomach with a diameter of less than 1.0 cm, surgical treatment is not absolutely necessary, and that, in comparison with the risks represented by surgical mortality and post operative morbidity, regular endoscopic/bioptic follow-up can be considered to be adequate.

Adult↗