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H Herrmann

Publications and source records attributed to H Herrmann.

At least 91 records · Page 5Linked to original sources
PubMed1988

Expression of intermediate filament proteins during development of Xenopus laevis. III. Identification of mRNAs encoding cytokeratins typical of complex epithelia.

A Xenopus laevis mRNA encoding a cytokeratin of the basic (type II) subfamily that is expressed in postgastrulation embryos was cDNA-cloned and sequenced. Comparison of the deduced amino acid sequence of this polypeptide (513 residues, calculated mol. wt 55,454; Mr approximately 58,000 on SDS-PAGE) with those of other cytokeratins revealed its relationship to certain type II cytokeratins of the same and other species, but also remarkable differences. Using a subclone representing the 3'-untranslated portion of the 2.4 kb mRNA encoding this cytokeratin, designated XenCK55(5/6), in Northern blot experiments, we found that it differs from the only other Xenopus type II cytokeratin known, i.e. the simple epithelium-type component XenCK1(8), in that it is absent in unfertilized eggs and pregastrulation embryos. XenCK55(5/6) mRNA was first detected at gastrulation (stage 11) and found to rapidly increase during neurulation and further development. It was also identified in Xenopus laevis cultured kidney epithelial cells of the line A6 and in the adult animal where it is a major polypeptide in the oesophageal mucosa but absent in most other tissues examined. The pattern of XenCK55(5/6) expression during embryonic development was similar to that reported for the type I polypeptides of the 'XK81 subfamily' previously reported to be embryo-specific and absent in adult tissues. Therefore, we used a XK81 mRNA probe representing the 3'-untranslated region in Northern blots, S1 nuclease and hybrid-selection-translation assays and found the approximately 1.6 kb XK81 mRNA and the resulting protein of Mr approximately 48,000 not only in postgastrula embryos and tadpoles but also in the oesophagus of adult animals. Our results show that both these type II and type I cytokeratins are synthesized only on gastrulation and are very actively produced in early developmental stages but is continued in at least one epithelium of the adult organism. These observations raise doubts on the occurrence of Xenopus cytokeratins that are strictly specific for certain embryonic or larval stages and absent in the adult. They rather suggest that embryonically expressed cytokeratins are also produced in some adult tissues, although in a restricted pattern of tissue and cell type distribution.

Amino Acid Sequence↗
PubMed1988

[The effect of time and dosage of isosorbide mononitrate on objective and subjective parameters in angina pectoris].

The efficacy of the isosorbide mononitrate preparations ISMN-20 (elantan 20) and ISMN-50 (elantan long) and the influence of the time of dosage on the quality of life was investigated in 3624 patients with the clinical diagnosis coronary heart disease and stable angina pectoris in an open multi-center trial. The frequency of attacks was significantly reduced (p less than 0.001) during 4 weeks of therapy. 35.4% of patients were free from attacks by the end of the trial. Consumption of acute nitrates decreased from an average of 5 to 2 applications per week. Circadian rhythm in the patients' profile of attacks remained unchanged under mononitrate therapy which allows the conclusion that this therapy is well adapted to the daily routine. The times of dosage of ISMN-20 (in the morning and at lunch-time or in the morning and in the evening) both had an identically good effect on the reduction of the attacks at night. ISMN-20 as well as ISMN-50 proved to provide efficient protection at night. After 4 weeks of therapy 86% of the patients showed an improvement of the loads of daily routine (climbing stairs, fast walking etc.). 71% noted an improvement in former limited recreational activities and 76.5% a relief concerning former limited activities in their job. 79.6% of patients felt an improvement of their quality of life by the mononitrate treatment. 70.8% of study patients were motivated for a consequent long-term therapy with the mononitrate with priority for the sustained release preparation.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

Plectin and IFAP-300K are homologous proteins binding to microtubule-associated proteins 1 and 2 and to the 240-kilodalton subunit of spectrin.

Structural and functional characteristics of plectin from intermediate filament preparations of rat glioma C6 cells were compared to those of the intermediate filament-associated protein of Mr = 300,000 (IFAP-300K) of baby hamster kidney cells (Yang, H.-S., Lieska, N., Goldman, A.E., and Goldman, R.D. (1985) J. Cell Biol. 100, 620-631). After radiolabeling and proteolytic digestion under varied conditions, both proteins yielded nearly identical peptide maps. Immunological cross-reactivity, co-migration on one- and two-dimensional high-resolution gels, chromatofocusing, and amino acid analysis demonstrated structural homology as well. In vivo labeling with 32Pi showed that plectin was the target for cAMP-independent protein kinases which phosphorylated 18-kDa domains at the end(s) of the molecule. Previously reported phosphorylation sites for cAMP-dependent and a newly identified site for Ca2+/calmodulin-dependent protein kinases were located on different domains. In solid-phase binding assays, plectin bound to vimentin, microtubule-associated proteins 1 and 2, the 240-kDa chain of brain fodrin, and alpha-spectrin from human erythrocytes. Similar characteristics were revealed for corresponding 300-kDa components of various other cell lines, supporting the concept that plectin is a general cytoskeletal cross-linking element, probably of multiple function.

Animals↗
PubMed1987

Left or right transaxillary approach in lower extremity arteriography for severe occlusive vascular disease. An anatomic study of a roentgenologic problem.

In an anatomic study of 46 specimens, the angle of the brachiocephalic trunk and the left subclavian artery to the tangent of the aortic arch was measured in an effort to decide which route offers the quickest access to the descending aorta in lower extremity angiography for severe occlusive vascular diseases. The study shows that the average angles (77.1 +/- 16.0 degrees for the brachiocephalic trunk/77.7 +/- 16.3 degrees for the left subclavian artery) are not significantly different. Since the right axillary approach incurs other risks that could only be compensated by significantly quicker access, i.e. shorter maneuvering time in the aortic arch we conclude that in patients of all ages the left side should be the access route of choice.

Aged↗
PubMed1986

Transductional analysis of the cysII region of Pseudomonas aeruginosa.

The close linkage between hisI and mutations of the cysII group in Pseudomonas aeruginosa was confirmed by mapping experiments with new mutants. All mutants of the cysII group were blocked in the cysteine biosynthesis before sulfite (this include the mutant cys-5605 which had previously been mapped by Mee and Lee, 1969). Most of the sulfite requiring cys mutants belonged to this group. The farthest distance between two mutations of the cysII group was calculated by the Wu formula to be approximately 2.5 kbp. We, therefore, suggest that more than one gene of the cysteine pathway may be located within this region.

Chromosome Mapping↗
PubMed1986

The Hfr status of Pseudomonas aeruginosa is stabilized by integrative suppression.

A temperature-sensitive mutant (dna-11) with the phenotype of a mutant defective in the initiation of DNA replication, was isolated from an Hfr-like FP2 donor of Pseudomonas aeruginosa. Reversion of its temperature-sensitive character was achieved by integrative suppression rather than by backmutation or an additional suppressor mutation. The dna-11 mutant proved to be helpful in stabilizing the Hfr status of the original host.

Conjugation, Genetic↗
PubMed1986

Molecular aspects of MAP-1 and MAP-2: microheterogeneity, in vitro localization and distribution in neuronal and nonneuronal cells.

We have studied various aspects of MAP-1 and MAP-2 from neuronal as well as nonneuronal sources. MAP-1 and MAP-2 polymerized from brain were resolved into a number of subcomponents upon electrophoresis on low percentage gels. Based on peptide mappings performed under a variety of different conditions, we conclude that the three major subcomponents of MAP-1 have very similar, though not identical structures. The two major MAP-2 subcomponents might have identical structure, because their peptide maps were hardly distinguishable. The apparent microheterogeneity of high Mr MAPs is not yet understood on a molecular basis. Proteolysis during isolation or a different degree of phosphorylation, however, seems to be an unlikely cause for microheterogeneity. When localized on microtubules polymerized in vitro by electron microscopy, both MAP-1 and MAP-2 polypeptides apparently form helical arrays on the polymer's surface with periodicities of 100 nm. In the presence of taxol, MAPs form irregular and bulky extensions. Both MAPs are found to be widespread in neuronal as well as nonneuronal cells. MAP-1- and MAP-2-related polypeptides, together with other high Mr proteins, such as plectin, were associated with microtubules polymerized by taxol from extracts of a nonneuronal cultured cell line. MAP-2 from cultured cells was found to be extremely sensitive to proteolysis, in particular in the presence of free Ca-ions. MAP-1 and MAP-2 generally were found associated with typical microtubule structures such as interphase and spindle microtubules and primary cilia. A differential distribution of MAP-1 and MAP-2 was clearly evident in neural tissues, where MAP-2 was restricted to cell bodies and dendrites, whereas MAP-1 was present also in axons. Moreover, a differential distribution of MAPs and tubulin was observed in de-and regenerating peripheral nerve, and in a few occasions, also with nonneuronal cells. A quite unexpected result was the identification of a protein in the extracellular matrix of cultured fibroblast cells, which has antigenic determinants in common with MAP-1 and MAP-2 from brain. As a whole, the data presented support a concept in which a family of structurally homologous, though not identical, high Mr polypeptides constitute the crosslinking elements between microtubules and various other cellular components. The structural diversity of these polypeptides might play a role in the development and dynamic changes in the cytoskeletal architecture.

Animals↗
PubMed1986

[Value of the maximal expiratory flow-volume diagram in a longitudinal study. 2. Results in young adults].

In a 3-year follow-up we have investigated random samples of young men (initial age 20 to 24 years) by means of the modified BMRC questionnaire and maximal expiratory flow-volume curves. The participation in the second survey was relatively poor (51.9 p.c.). The lung function data of asymptomatic non-smokers were in good accordance with reference values of other authors. We found significant differences between smokers and non-smokers already in this age group. There was no correlation with the extent of smoking. Cessation of smoking resulted in improved ventilatory data, especially MEF 50. We found no close relation between bronchitis symptoms and ventilatory disturbances in these young men. Wheezing correlated better with lung function impairment. In young male adults the flow-volume curve seems to be somewhat more sensitive than conventional spirometry in contrast to the results in elder subjects.

Adult↗
PubMed1985

[Hyperprolactinemia and prolactinomas. Results of surgical and drug therapy].

185 patients with hyperprolactinaemia and prolactinoma were evaluated in a retrospective investigation. 128 patients were treated surgically whereby the prolactin serum level in 47% of the macroprolactinoma and 60% of the microprolactinoma patients was normalised (prolactin less than 25 ng/ml, no radiological evidence of tumor). Of those patients in whom the operation was less successful, a normal prolactin level could be achieved in 77% by additional therapy with dopamine agonists. Of 57 patients handled exclusively with drugs, the prolactin level was normalised by dopamine agonists in 78%. A small number of patients from both groups did not show a satisfactory fall in the prolactin level despite the use of markedly higher doses of dopamine agonists. During dopamine agonist therapy progressive tumor enlargement was detected radiologically in a previously operated patient.

Adolescent↗
PubMed1985

Microheterogeneity of microtubule-associated proteins, MAP-1 and MAP-2, and differential phosphorylation of individual subcomponents.

High molecular weight microtubule-associated proteins 1 and 2 (MAP-1 and MAP-2), prepared by copolymerization with tubulin, were electrophorectically separated into three and two major subcomponents, respectively, using 5% sodium dodecyl sulfate-polyacrylamide gels. By two-dimensional gel electrophoresis, all five MAP components were shown to possess a pI of around 5. Four of these proteins, MAP-1A, MAP-1C, MAP-2A, and MAP-2B, present in comparable amounts, were iodinated after electrophoretic separation and analyzed by two-dimensional peptide mapping. With both trypsin and V8 protease, almost identical patterns were obtained from MAP-2A and MAP-2B. MAP-1A and MAP-1C, too, gave similar digestion patterns, although some differences were noted. Incubation with [gamma-32P]ATP demonstrated that endogeneous protein kinase activities phosphorylated individual subcomponents at different rates. MAP-2A, the highest labeled component, was phosphorylated 2.5-fold compared to MAP-2B both in the presence and the absence of cAMP. Labeling of MAP-1 subcomponents was 4 times less than that of MAP-2A in the absence and 16 times less in the presence of cAMP. 32P-labeled MAP-2A and MAP-2B bands were indistinguishable by one-dimensional peptide mapping, as were the three MAP-1 bands. For both MAP-1 and MAP-2 subcomponents, cAMP induced phosphorylation at new molecular sites. Incubation of radiolabeled microtubule proteins with 1 mM ATP effected, upon electrophoresis, a clear shift of MAP-2A and MAP-2B bands to positions of higher apparent molecular weights, while only slightly affecting MAP-1 bands.

Adenosine Triphosphate↗
PubMed1985

[Psychological considerations in the wish for refertilization].

51 women asking for refertilization were evaluated by means of a half-standardized questionnaire before laparoscopy. Special attention was directed towards the psychological situation at the time of sterilisation as well as the reasons for refertilization desired. In addition the Giessen-test was performed as standardized psychological personality inventory. In general, the sterilization was initiated by the women because of social, financial or marital difficulties. In 2/3 of the females sterilization was performed in association with other gynecological or obstetrical procedures. Most of the women did not have any kind of adequate psychological or social counseling. The desire for refertilization was mainly caused by changes in the personal situation. 29 of 51 women reported to have a new partner, 27 of them after divorce or separation, two after the previous partner's death. Ten women reported the loss of a child, however, 12 women desired refertilization without any obvious change in their private situation. In conclusion, it appeared that refertilization was desired and experienced as a real need as well as a result of a conflict in the women's self-understanding expressed by a tendency towards depression.

Adaptation, Psychological↗
PubMed1985

Monoclonal antibody to a 43 000 Mr surface protein of a human leukaemia cell line (THP-1) crossreacts with the fibroblast intermediate filament protein vimentin.

Monoclonal antibodies were produced against surface antigens of live cells from a human acute monocytic leukaemia cell line (THP-1). One clone, VIC-C2, when assayed by immunofluorescence microscopy, brightly stained the surface of THP-1 cells and the cytoplasm of Langerhans cells, fibroblasts and melanocytes in sections of human skin. The immunoreactive cytoplasmic structures were filamentous and resembled intermediate filaments. By double immunofluorescence microscopy using VIC-C2 and polyclonal antibodies to vimentin, the VIC-C2 antigen was shown to be located on intermediate filaments of cultured fibroblasts and to follow these filaments during various drug-induced rearrangements. As demonstrated by immunoprecipitation, antibody gel overlay and immunoblotting of two-dimensional polyacrylamide gels, VIC-C2 recognized two different antigens in extracts of THP-1 cells: one of Mr = 43 000 and pI = 7, the other of Mr = 57 000. In extracts from various cultured fibroblast cells only the 57 000 Mr antigen was detected. This 57 000 Mr protein was identified as vimentin by immunoblotting of rat glioma C6 cytoskeletons on two-dimensional gels. When vimentin was digested with chymotrypsin, only fragments containing parts of both helical rod pieces and the connecting non-helical spacer-region were strongly antigenic, whereas the helical rods alone were only weakly crossreactive. Moreover, immunoprecipitation revealed that VIC-C2 preferentially reacted with native compared to denatured vimentin.

Antibodies, Monoclonal↗
PubMed1985

Variability in the pharmacokinetics of atenolol and metoprolol.

18 healthy volunteers received conventional atenolol (Tenormin) 50 mg once daily and metoprolol 50 mg twice daily for 6 days in a balanced randomised cross-over fashion. There was a wash-out period of two weeks between each phase. Plasma concentrations of the drugs were measured on the last day of each phase. Comparison of the coefficients of variation showed a lower variability in the pharmacokinetics of atenolol compared to metoprolol. The clinical implications of these findings are discussed.

Adolescent↗
PubMed1985

[Value of the maximal expiratory flow-volume diagram in a longitudinal study].

In a 4-year follow-up we have measured the maximal expiratory flow-volume curve in a random sample of the population of a hydrogen chloride air-polluted area. At the first investigation the pressure transducer of our pneumotachograph had shown an unsatisfactory frequency characteristic. Therefore the initial flow of the flow-volume curve (PEF and MEF 75) were underestimated. The values for asymptomatic non-smokers of the restudy were in good accordance with reference values of other authors. On both occasions we found significant differences between smokers and non-smokers and between persons with and without bronchitis. The lung function data correlated also with tobacco consumption. There was no evidence for superiority of the maximal expiratory flow rates over the conventional spirometric parameters FEV1 and FVC.

Adult↗