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H Herrmann

Publications and source records attributed to H Herrmann.

At least 73 records · Page 4Linked to original sources
PubMed1993

[Suspected vaccination complications or atypical vaccination course. Diagnostic assessment of 58 vaccine recipients].

The "list of recommended vaccinations" of the regional Ministries of Health is the legal basis for routine vaccination programmes in each region of Germany; the recommendations of the Federal Commission on Vaccinations, "STIKO", are not legally binding. These programmes of the different regions provide legal grounds for determining claims for damage against a vaccinating doctor. In cases of damage, the Ministry of Health is liable for the damage to a patient caused by a recommended vaccination. Irrespective of these clear and comprehensive legal provisions, in case of an atypical course the patient is entitled to careful diagnosis of the complaint and appropriate medical treatment. However, later claims by the patient for damage can only be decided correctly if the necessary diagnostic data have been carefully collected at the acute stage of the disease. In our 58 patients suffering from atypical vaccination courses or suspected complications, we were able to show in each case that the symptoms are the result of interference by infectious diseases or that there was some other clear diagnosis; in no case did we find that the vaccination had caused disease or permanent damage.

Adolescent↗
PubMed1992

Identification of a nonapeptide motif in the vimentin head domain involved in intermediate filament assembly.

The assembly of soluble vimentin subunits into intermediate filaments (IFs) is dependent on information located in the amino-terminal domain. Using site-directed mutagenesis of a Xenopus laevis vimentin cDNA and an Escherichia coli production system to obtain pure mutated protein, we have identified, in the head domain, a nine amino acid motif (SSYRRIFGG), evolutionarily conserved from amphibia to man, which plays an important role in the orderly formation of IFs. Exchanges in the central di-arginine and in the two aromatic residues interfere with IF assembly of vimentin in vitro: on assembly under standard assembly conditions (160 mM-NaCl) most of the protein is included in dense aggregates, with a variable and minor proportion of IFs, whereas at lower ionic concentrations short and incomplete IF-like structures are formed. The deletion of the whole motif results in a protein that under standard assembly conditions (e.g. 160 mM-NaCl) predominantly and rapidly precipitates into large aggregates of non-IF material, whereas at lower ionic strength (e.g. 50 mM-NaCl) both IFs and dense aggregates are formed simultaneously. Our results show that the mutated protein can assume different forms at the same time and under the same conditions. This motif alone is insufficient for the formation of normal IFs as demonstrated by a mutant in which the motif has been brought closer to the alpha-helical rod domain by deletion of 55 internal amino acid residues. Corresponding observations have been made, by immunofluorescence microscopy, upon transfection of cultured epithelial cells lacking vimentin IFs. The importance of the head domain motif for the assembly and higher-order arrangement of IFs is discussed.

3T3 Cells↗
PubMed1992

An expression vector system providing plasmid stability and conditional suicide of plasmid-containing cells.

A cloning vector system was constructed on the basis of the pBR322 derivative pEG1 by introducing the whole parB locus of plasmid R1 cloned behind the promoter of the alkaline phosphatase gene (phoA) of Escherichia coli. The parB locus in combination with the phoA promoter ensures both (i) plasmid stabilization due to the post-segregational killing of plasmid-free cells during growth and (ii) killing of the cells induced by the potential environmental signal phosphate limitation. This vector, therefore, appears to be a model system for increasing the stability of recombinant plasmids and for decreasing the potential risks in the application of recombinant bacteria in industrial fermentations.

Alkaline Phosphatase↗
PubMed1992

Interference in vimentin assembly in vitro by synthetic peptides derived from the vimentin head domain.

The importance of the amino-terminal domain ("head") of type III intermediate filament (IF) proteins in IF assembly has been examined by testing the influence of synthetic peptides representing a highly conserved decameric motif, KSSSYRRIMFGG, located near the amino terminus of vimentin. When added to soluble vimentin subunits this peptide induces, at fourfold molar excess or slightly above, the appearance of short, regular rod-like structures as determined by electron microscopy of negatively stained and rotary-shadowed preparations as well as by viscometry. At higher peptide concentrations large, irregularly shaped aggregates of mostly non-IF structures formed, but this aggregation was reversible by prolonged dialysis against low ionic strength buffer. The aggregating effect of this peptide was highly sequence-specific and was not seen with point-mutated sequences such as RR----TR or with unrelated peptides containing a central diarginine, indicating that it is not simply ionic. When different hexapeptides representing different "head" positions were compared, only the central sequence, SYRRXF, was as effective as the decamer. The addition of peptide during IF assembly did not prevent filament formation, although 50-fold molar excess of peptide resulted in a drastic increase (up to 40 nm) in the width of the filaments, which also appeared less regular, thus reflecting some interference with assembly. In contrast to the effects on soluble vimentin, the decameric peptide did not disturb IFs, indicating that the binding domain is "masked" or stabilized in the filaments. To identify the domain to which the peptide binds, three different binding assays using vimentin fragments and genetically engineered vimentin deletion mutants were employed. The results indicate that the binding domain of the near-amino-terminal peptide is located at the start of the alpha-helical "rod" domain of the protein. Possible mechanisms of interaction of these two portions of vimentin during IF assembly are discussed.

Amino Acid Sequence↗
PubMed1992

Assembly of a tail-less mutant of the intermediate filament protein, vimentin, in vitro and in vivo.

Recent reports on the possible contribution of the non-alpha-helical carboxy-terminal domain ("tail") of type III intermediate filament (IF) proteins to IF assembly have been controversial. To examine the importance and role of this domain, we have therefore engineered a Xenopus laevis vimentin cDNA to code for a tail-less polypeptide and have used it in combination with prokaryotic and eukaryotic expression systems. Here we show that tail-less vimentin, isolated from transfected bacteria (Escherichia coli), when used for assembly in vitro, forms normal-looking, loosely packed IFs. By viscometry we demonstrate that this tail-less vimentin assembles at an even higher rate and into longer IFs than wild-type vimentin. In vivo, i.e., by forced expression in transfected type III IF-free cultured epithelial cells, tail-less vimentin was also recovered in short fibrillar structures, in rodlets and in small as well as large spheroidal aggregates ("granules") that did not reveal any IF substructure. Surprisingly, however, spheroidal aggregate structures formed from the tail-deleted vimentin, were seen not only in the cytoplasm but also in the nucleus, indicating a role of the tail in higher order organization and compartmentalization of the vimentin IF system.

Animals↗
PubMed1991

Assembly and structure of calcium-induced thick vimentin filaments.

Using a viscometric assay and various electron microscopic procedures (negative staining, rotary shadowing, ultrathin sectioning) we have determined the influences of different kinds of ions and of ionic strength on the structures formed by assembly of soluble subunits of vimentin from bovine lens tissue or from Escherichia coli transformed with Xenopus vimentin cDNA. In contrast to the assembly of typical, i.e., 8 to 14-nm, intermediate-sized filaments (IFs) at elevated (e.g., 160 mM) concentrations of monovalent cations and at millimolar Mg2+ concentrations, filaments formed in the presence of Ca2+ ions (e.g., 5 mM) appeared at a lower rate, attained lower viscosity and were considerably thicker and shorter. The largest diameter measured was that for the recombinant amphibian protein: 24.2 +/- 8.5 nm in negative staining, 28.7 +/- 5.6 nm in sections. These thick Ca(2+)-induced filaments, however, revealed the same approximately 2 nm protofilament composition and approximately 20 nm cross-striation pattern as typical IFs, indicative of a similar molecular arrangement. The significance of this unusual structural IF protein assembly is discussed.

Animals↗
PubMed1990

[Long-term therapy of tumor pain using morphine-retard tablets].

We analysed the effect of sustained-release morphine tablets in 174 patients with severe cancer pain. A good relief of pain could be obtained in 65% of the patients within the first week and in 80% of the patients at the end of therapy. The mean daily dose was at 178 mg morphine, six patients needed more than 1000 mg per day. The sustained-release morphine was given at fixed intervals, in 80% of the cases every eight hours. No severe side-effects were associated with long-term morphine therapy. We often saw nausea and vomiting, constipation and drowsiness, but these side-effects decreased after the first weeks of treatment. Only in ten patients we had to stop therapy because of side-effects. Morphine can be used successfully in the treatment of cancer pain for long periods without concern about tolerance.

Administration, Oral↗
PubMed1990

Lidocaine metabolite formation as a measure of liver function in patients with cirrhosis.

A method for rapid assessment of hepatic function in cirrhotics based on the formation of the lidocaine metabolite, monoethylglycinexylidide (MEGX), was evaluated. The formation kinetics and urinary excretion patterns of MEGX clearly distinguished cirrhotics (n = 12) from healthy volunteers (n = 16). In a prospective study, we compared the prognostic value of the MEGX test with that of traditional parameters in transplant candidates. Patients who underwent transplantation during follow-up were excluded. The study included 58 adult patients with biopsy-proven posthepatitic or biliary cirrhosis. During the follow-up period of 120 days, 10 of 58 patients died of their liver disease. At the time of inclusion, we recorded MEGX formation, indocyanine green (ICG) half-life, caffeine clearance, and the Child-Pugh score. These variables were subjected as covariates to a survival analysis (Cox proportional hazards regression model). The results of the MEGX and the ICG test were significantly related to the 120-day survival. In the stepwise analysis, none of the parameters evaluated contributed to a further significant improvement of our predictive ability when added to the values of ICG (improvement: p less than 0.0005) and MEGX (improvement: p less than 0.0005). These findings suggest that the ICG and MEGX tests were the best short-term prognostic indicators. The easy handling favors the MEGX test over the ICG test as a tool for assessment of hepatic function and short-term prognosis in transplant candidates with cirrhosis.

Adult↗
PubMed1990

[Comparative study of parenteral and oral immunization to influenza in a large clinical trial. 1. Results of clinico-epidemiologic studies].

360 volunteers were recruited for the investigation from a homologous collective. 174 were immunized parenterally with "Influmun" from SSW Dresden, GDR. 176 volunteers were immunized twice orally with an interval of 60 days with an influenza vaccine inactivated by x-ray using enteric-coated capsules. In an interval of six months ARI-symptoms were investigated. Between 13th and 17th week 1988 an increased ARI-morbidity in the Greifswald-region was observed in which influenza A viruses were involved. In comparison with 312 non-immunized persons of the same age, sex and living area the immunized volunteers of the two groups showed 83.4% less sickness days. 30 persons of the non-immunized group got ill for totally 217 days, whereas only nine persons of the two immunized groups were put on the sicklist for totally 36 days. No significant differences concerning the occurrence and duration of acute respiratory infections (ARI) between the two differently immunized groups could be observed.

Administration, Oral↗
PubMed1989

Lignocaine metabolite formation as a measure of pre-transplant liver function.

A method for rapid assessment of hepatic function in liver donors based on the formation of the lignocaine metabolite monoethylglycinexylidide (MEGX), was used in a prospective study of 69 donor-recipient pairs. The probability of graft survival over 120 days was significantly higher for livers from donors with MEGX test values above 90 micrograms/l than for those from donors with MEGX values of 90 micrograms/l or below. Other liver function tests (bilirubin, prothrombin time, activity of aminotransferases, glutamate dehydrogenase, and cholinesterase, indocyanine green clearance, and galactose elimination capacity) were inefficient at predicting early outcome of transplantation. For a 20-day graft survival, the MEGX test showed prognostic sensitivity of 73% and specificity of 78%. These findings suggest that the MEGX formation test could be valuable for selection of donor organs.

Adolescent↗
PubMed1989

[Therapy of sterility from the viewpoint of females].

361 gynecological out-patients were questioned by means of a standardised questionnaire concerning their attitude towards the following possibilities of therapy procedures in case of sterility: 1. Artificial Insemination by Husband (AIH) 2. Artificial Insemination by Donor (AID) 3. In Vitro Fertilization (IVF) 4. Surrogate motherhood 5. Microsurgery Clearly positive was their attitude towards microsurgery, AIH and IVF. The patients would, in case of a corresponding sterility problem, accept such therapy for themselves. Negative, however, was their attitude towards AID and surrogate motherhood. Acceptance turned out to be significantly higher in regard to the medically and psychologically more precarious procedures like IVF, AID and surrogate motherhood, when asked whether they would tolerate such therapy for other involuntarily childless couples. Acceptance and valuation of procedures repeatedly followed the same order: microsurgery was judged "most moral" and "most natural", then AIH, IVF, AID and last surrogate motherhood. So traditional ideas of standards and values are decisive factors of acceptance. Emotionally the experience of sexuality, the progenitive act and pregnancy seem to belong together. The more a medical-technical procedure will interfere with their privacy the less it will be accepted. No difference in attitude was to be detected in regard to demographic criterions like age or religion. Sterile women, however, were far more prepared to undergo a physically as well as emotionally strenuous therapy in order to have their childwish come true. Personal involvement plays a decisive role in the acceptance of medically and psychologically more precarious procedures like IVF and AID. In comparison the extent of medical-technical efforts, and health risks, seem to be of minor importance.

Adolescent↗
PubMed1989

Expression of intermediate filament proteins during development of Xenopus laevis. I. cDNA clones encoding different forms of vimentin.

To provide a basis for studies of the expression of genes encoding the diverse kinds of intermediate-filament (IF) proteins during embryogenesis of Xenopus laevis we have isolated and characterized IF protein cDNA clones. Here we report the identification of two types of Xenopus vimentin, Vim1 and Vim4, with their complete amino acid sequences as deduced from the cloned cDNAs, both of which are expressed during early embryogenesis. In addition, we have obtained two further vimentin cDNAs (Vim2 and 3) which are sequence variants of closely related Vim1. The high evolutionary conservation of the amino acid sequences (Vim1: 458 residues; Mr approximately 52,800; Vim4: 463 residues; Mr approximately 53,500) to avian and mammalian vimentin and, to a lesser degree, to desmin from the same and higher vertebrate species, is emphasized, including conserved oligopeptide motifs in their head domains. Using these cDNAs in RNA blot and ribonuclease protection assays of various embryonic stages, we observed a dramatic increase of vimentin RNA at stage 14, in agreement with immunocytochemical results obtained with antibody VIM-3B4. The significance of very weak mRNA signals detected in earlier stages is discussed in relation to negative immunocytochemical results obtained in these stages. The first appearance of vimentin has been localized to a distinct mesenchymal cell layer underlying the neural plate or tube, respectively. The results are discussed in relation to programs of de novo synthesis of other cytoskeletal proteins in amphibian and mammalian development.

Amino Acid Sequence↗
PubMed1989

Expression of intermediate filament proteins during development of Xenopus laevis. II. Identification and molecular characterization of desmin.

During embryogenesis of avian and mammalian species the formation of intermediate filaments (IFs) containing desmin is characteristic for myogenesis. In view of important differences of patterns of IF protein expression in embryogenic pathways of amphibia on the one hand and birds and mammals on the other, we have decided to study the expression of desmin during early embryogenesis of Xenopus laevis by cDNA hybridization and antibody reactions. Here we describe the isolation of a cDNA clone encoding Xenopus desmin and the deduced amino acid sequence (458 residues; Mr 52,800) which displays a very high degree of conservation during vertebrate evolution from Xenopus to chicken and hamster, with a similar degree of sequence divergence between all three species compared. In addition, we have noted, by both cDNA-hybrid-selection-translation and immunoblotting of cytoskeletal proteins a second desmin-related polypeptide of Mr approximately 49,000. RNA (Northern) blot analyses show the occurrence of three different desmin mRNAs (1.9, 2.6 and 3.0 kb) which seem to represent different polyadenylation sites, displaying quantitative differences in different kinds of muscle tissues. During embryogenesis, desmin mRNA has first been detected in stage-14 embryos and then increases drastically to high levels at stage 18 and thereafter. Immunofluorescence microscopy using desmin-specific antibodies shows that this synthesis of desmin is restricted to somite tissue. The embryonic time course of synthesis of desmin and desmin mRNA is discussed in relation to those of other muscle proteins.

Amino Acid Sequence↗
PubMed1988

[Epidemiology and strategy for the control of chronic respiratory diseases].

The conditions of tertiary prevention of chronic bronchitis are determined by prevalence, number of cases of inability to work, time of disease periods and age-depending mortality. An age-specific increase could be proved for all parameters. The critical age-line is about the 50th year of age. 75% of the bronchitis patients under medical care are older than 50 years of age. Measure of care ought to be concentrated on the time before the 50th year of age and on cases of risk. By an earlier beginning of medical care it is possible to increase the efficiency of tertiary prevention.

Cross-Sectional Studies↗
PubMed1988

In vivo generation of R68.45-pPGH1 hybrid plasmids conferring a Phl+ (meta pathway) phenotype.

Plasmid pPGH1 originating from Pseudomonas putida strain H carries all the genes required for the degradation of phenol (or cresols) via the meta cleavage pathway. Besides mobilization of pPGH1 by a plasmid of the incompatibility group P-1, hybrid plasmids conferring the Phl+ phenotype could be selected, when R68.45 was the conjugative plasmid. The hybrids contain the complete R68.45 and part of pPGH1. Integration of Phl-DNA of pPGH1 into R68.45 occurred exclusively via the IS21 region of R68.45.

Cloning, Molecular↗
PubMed1988

Cytoskeleton-associated plectin: in situ localization, in vitro reconstitution, and binding to immobilized intermediate filament proteins.

The association and interaction of plectin (Mr 300,000) with intermediate filaments and filament subunit proteins were studied. Immunoelectron microscopy of whole mount cytoskeletons from various cultured cell lines (rat glioma C6, mouse BALB/c 3T3, and Chinese hamster ovary) and quick-frozen, deep-etched replicas of Triton X-100-extracted rat embryo fibroblast cells revealed that plectin was primarily located at junction sites and branching points of intermediate filaments. These results were corroborated by in vitro recombination studies using vimentin and plectin purified from C6 cells. Filaments assembled from mixtures of both proteins were extensively crosslinked by oligomeric plectin structures, as demonstrated by electron microscopy of negatively stained and rotary-shadowed specimens as well as by immunoelectron microscopy; the binding of plectin structures on the surface of filaments and cross-link formation occurred without apparent periodicity. Plectin's cross-linking of reconstituted filaments was also shown by ultracentrifugation experiments. As revealed by the rotary-shadowing technique, filament-bound plectin structures were oligomeric and predominantly consisted of a central globular core region of 30-50 nm with extending filaments or filamentous loops. Solid-phase binding to proteolytically degraded vimentin fragments suggested that plectin interacts with the helical rod domain of vimentin, a highly conserved structural element of all intermediate filament proteins. Accordingly, plectin was found to bind to the glial fibrillar acidic protein, the three neurofilament polypeptides, and skin keratins. These results suggest that plectin is a cross-linker of vimentin filaments and possibly also of other intermediate filament types.

Animals↗