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S Hahn

Publications and source records attributed to S Hahn.

At least 235 records · Page 13Linked to original sources
PubMed1986

[Euthanasia in the Third Reich--only a problem of psychiatry? On the development of the euthanasia debate 1933-1941 in Germany].

The devastating consequences of the Fascist dictatorship in Germany for the ethical thinking of the physicians are particularly clearly recognizable by the mass killings of severely damaged children and patients with chronic psychic diseases which were performed at that time. Recent investigations of the developments which began in 1938 show that by way of intensive efforts for a juridicial legalization of the "active euthanasia" an enlargement of this killing practice has been striven after. References to a motive of compassion and the free decision of the affected persons should cover the real intention for reducing welfare services. A bill presented in 1940 for a law "on euthanasia for incurable ill persons" found the unanimous consent of the renowned physicians consulted for this purpose. Though this law finally did not become legal beginning with 1941 the medical practice showed further forms of the repressive and antihumane association with ill persons who were regarded as incurable, which must be valuated as practical consequences of an unadmissible relativation of the life-preserving task of medicine.

Euthanasia↗
PubMed1985

Each of three "TATA elements" specifies a subset of the transcription initiation sites at the CYC-1 promoter of Saccharomyces cerevisiae.

Transcription initiation of the yeast iso-1-cytochrome c gene (CYC-1) occurs in six major clusters at positions +1, +10, +16, +25, +34, and +43. Potential "TATA elements" lie upstream at positions -154, -106, -52, and -22. Analysis of the TATA region suggests that three of these TATA sequences are functional and contribute to initiation at CYC-1, with the -106 TATA promoting initiation at +1, +10, and +16; the -52 TATA, at +16, +25, +34, and +43; and the -22 TATA, at +34 and +43. Deletions changing the spacing between the TATA sequences and the region of transcription initiation do not change the location of the CYC-1 transcription start points. This finding suggests that at least part of the information determining mRNA initiation sites is encoded within the DNA sequence at the site of transcription initiation. Analysis of 18 yeast RNA polymerase II promoters suggests that two classes of DNA sequences serve as preferred sites for transcription initiation. To test this possibility, we replaced some of the normal CYC-1 start sites with one of these sequences, TCGA, and found that transcription initiates at this newly introduced sequence. These results are in contrast to those from higher eukaryotes, where RNA polymerase II typically initiates transcription a fixed distance downstream from the TATA element. The presence of multiple, functional TATA sequences at CYC-1 is inconsistent with the idea that RNA polymerase or another transcription factor attaches to the template at an upstream activation site and scans for the nearest TATA element.

Base Sequence↗
PubMed1985

Effect of cleavage of the heavy chain of human plasma kallikrein on its functional properties.

Human plasma kallikrein consists of an N-terminal heavy chain of molecular weight (mol wt) 52,000, linked by disulfide bonds to two light chain variants (mol wt 36,000 or 33,000). Although the active catalytic site of kallikrein resides on the C-terminal light chain, the role of the N-terminal heavy chain is less clear. We therefore studied an enzyme designated beta-kallikrein, containing a single cleavage in the heavy chain (mol wt 28,000 + 18,000) and compared it to the enzyme, alpha-kallikrein, with an intact heavy chain. The rates of inactivation by C1 inhibitor of plasma alpha- and beta-kallikreins were kinetically identical, as measured by residual amidolytic activity, after various times of incubation with the inhibitor. Both enzymes reacted completely with C1 inhibitor after 18 hours and formed identical C1 inhibitor-kallikrein complexes of mol wt 195,000. The rate of activation of factor XII by alpha-kallikrein and beta-kallikrein was similar. In contrast, the rate of cleavage of high molecular weight kininogen (HMWK) by alpha-kallikrein was at least fivefold faster and the ratio of coagulant activity to amidolytic activity was fourfold greater than for beta-kallikrein. Plasma alpha-kallikrein, at concentrations potentially achievable in plasma, induced aggregation of neutrophils, but beta-kallikrein failed to elicit this response. In addition, human neutrophils pretreated with cytochalasin B released 2.46 +/- 0.10 microgram/10(7) cells of elastase antigen, but beta-kallikrein released only 0.25 +/- 0.10 micrograms/10(7) cells. These observations suggest that cleavage of the heavy chain influences the rate of cleavage of HMWK and decreases its coagulant activity. Moreover, an intact heavy chain appears to be requisite to support the ability of kallikrein to aggregate neutrophils and release elastase.

Blood Coagulation Tests↗
PubMed1984

Upstream repression and CRP stimulation of the Escherichia coli L-arabinose operon.

Repression of the Escherichia coli araBAD promoter, PBAD, was studied using a mutant PBAD promoter (cip-5) that is expressed in the absence of the two proteins required for PBAD induction, AraC protein and the cyclic AMP receptor protein (CRP-cAMP). Like the wild type promoter, cip-5 was repressed by AraC protein, and this repression required a site well upstream of the transcriptional start site. cip-5 was used to determine whether repression results from interference with the functioning of either AraC protein at araI and/or CRP-cAMP. Repression of cip-5 was eliminated by a point mutation within the AraC protein binding site araI but was not affected in the absence of CRP-cAMP. These results suggest that repression involves an interaction between two AraC protein binding sites located over 200 nucleotides apart. Our results also suggest that the majority of the CRP requirement for PBAD is a result of PBAD repression. When repression was abolished by deletion of the araO2 site, the requirement for CRP-cAMP in PBAD induction was greatly reduced.

AraC Transcription Factor↗
PubMed1984

[Medical ethics in the life of a physician of the soul--reflections on the medical ethics concept of Albert Moll (1862-1936)].

In the historical elaboration of tradition-determining conceptions concerning medico-ethical positions Albert Moll's (1862-1936) book "Ethics of the Physician" published 1902 forms an important marking point. Despite all discrepancy of Moll and his work in this book even nowadays valuable considerations for situations of medico-ethical decisions are mediated and evidences of the strive for the preservation of humanistic traditions in medicine are given. With the aim to give suggestions for modern medico-ethical considerations and to appreciate Albert Moll's work for the at present working physicians his life and work as well as his medico-ethical aim are represented and critically valuated.

Ethics, Medical↗
PubMed1984

An operator at -280 base pairs that is required for repression of araBAD operon promoter: addition of DNA helical turns between the operator and promoter cyclically hinders repression.

A site has been found that is required for repression of the Escherichia coli araBAD operon. This site was detected by the in vivo properties of deletion mutants. In vitro protection studies with DNase I and dimethylsulfate showed that araC protein can specifically bind in this area to nucleotides lying at position -265 to -294 with respect to the araBAD operon promoter (PBAD) transcription start point. The previously known sites of protein binding in the ara operon lie between +20 and -160. Since the properties of deletion strains show that all the sites required for araBAD induction lie between +20 and -110, the new site at -280 exerts its repressive action over an unusually large distance along the DNA. Insertions of -16, -8, 0, 5, 11, 15, 24, and 31 base pairs of DNA between the new site and PBAD were constructed. Repression was impaired in those cases in which half-integral turns of the DNA helix were introduced, but repression was nearly normal for the insertions of 0, +11, and +31 base pairs.

AraC Transcription Factor↗
PubMed1983

[Martin Luther--what does he say to use physicians today?].

On the occasion of the 500th anniversary of the reformer's birthday is tried to elaborate his ethical positions, significant for the medicine of his and the following time. This is done with the aim to use dialectically Luther's progressive thoughts for medico-ethical considerations concerning problems of our time and to oppose those persons who intend to render Luther a chief witness of misanthropic medicine.

Ethics, Medical↗
PubMed1983

[Winuron - alternative single-dose therapy of gonorrhea].

152 ambulatory patients suffering from gonorrhoea were treated with Winuron in an open clinical trial. A single oral dose of rosoxacin 300 mg proved to be sufficient to cure 97.4% of the patients. Follow-up examination revealed only 4 cases of Neisseria gonorrhoea left. Already 3 days after therapy, the clinical symptoms had subsided in 84.1% of the patients. The substance was well-tolerated. Side effects were observed in 14.5% of the cases, being mild and transitory, though. Good and antibacterial efficacy of rosoxacin in vitro as well as the high healing quotient in combination with the shortest possible duration of therapy make Winuron a valuable alternative to penicillin.

4-Quinolones↗
PubMed1983

[Ethical aspects of tuberculosis control under fascism].

At the instance of the development of the tuberculosis control in the period from 1933 to 1945 is tried to elaborate the ethical principles which are the basis of the medical care of the German population in fascist Germany. The utilitaristic and biologistic opinions of the value dominating at this time proved as altogether characterized by the social aims of fascism and at the same time serve for their realization in the field of health politics. Also in the tuberculosis control--like in other social fields--transitory progress in organisation and prophylaxis and finally to be paid with deranging setbacks which reveal the inhumanity of fascism also in this field.

Ethics, Medical↗
PubMed1983

In vivo regulation of the Escherichia coli araC promoter.

The ara pC promoter is known to be derepressed about fivefold for 20 to 30 min after the addition of arabinose. This transient derepression was studied by using araC::Mu lac insertions and araC-lacZ gene fusions. In strains containing increased levels of araC protein, the pC promoter became progressively less derepressible, but the ara pBAD promoter remained normally inducible. Repression of pC was reestablished 20 min after induction in araB mutants, but did not occur in arabinose-transport-deficient mutants. Finally, mutant araCc proteins which normally do not repress pC did so in the presence of arabinose.

Arabinose↗
PubMed1983

[Not Available].

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History, Ancient↗
PubMed1982

[Formation of progressive bourgeois opinions on the life-sustaining task of medicine and the care of dying patients at the beginning of the 19th century in Germany].

The ethical opinions concerning the task of medicine to sustain life which form themselves as a consequence of the development of the bourgeois society including concrete opinions concerning the care of dying patients, as they were elaborated e.g. by Hufeland and Reil at the beginning of the 19th century, are described. These ethical positions may as a historical approach contribute to the solution of modern medico-ethical problems in the preservation of life and the care of dying patients in medicine.

Attitude to Health↗