PubMed Health⌕ Search

Biomedical subjects

H Bastian

Publications and source records attributed to H Bastian.

16 recordsLinked to original sources
PubMed1996

Competing or complementary? Ethical considerations and the quality of randomized trials.

The ethical principles of beneficence (doing the best for one's patients and clients), nonmaleficence (doing no harm), autonomy, justice, and equity, are positively associated with the quality of a trial rather than being opposed to it. Ethical considerations involve such important questions as appropriate design and documentation, participation rates, withdrawals or losses to follow-up, careful monitoring of safety and efficacy, timely completion, generalizability, and publication and dissemination of findings. When conflicts between ethical considerations and the trial's scientific quality do occur, the ethical considerations must be paramount.

Ethics Committees↗
PubMed1996

Raising the standard: practice guidelines and consumer participation.

Clinical practice guidelines are increasingly affecting the quality of health care, and have the potential to affect the availability of health care options for consumers. Deciding what guidelines will cover, how they will be developed and what they will say are, therefore, issues in which consumers have a considerable stake. While there is a growing acknowledgement of the need to involve consumers in guideline development, the reality can fall far short of the rhetoric. This article advocates the use of three types of strategies in combination to enable better consideration of consumers' views in the guideline development process: the involvement of accountable consumer representatives in group decision making, community consultation and the use of research literature describing people's experiences. A framework for assessing the level of consumer participation in an activity is suggested. It is argued that if consumer involvement is to successfully raise the standard of health care guidelines, then the standard of consumer participation itself needs to be raised.

Attitude of Health Personnel↗
PubMed1993

Personal beliefs and alternative childbirth choices: a survey of 552 women who planned to give birth at home.

In Australia, planning to give birth at home was unusual in the middle to late 1980s, a choice made by only about 0.5 percent of women. This study investigated the personal beliefs and circumstances of 552 women who planned to give birth at home. Results showed that these women came from diverse backgrounds and beliefs, although in general they were of higher than average educational and occupational status, and less likely to hold Christian beliefs relative to the Australian community in general. Their lives and experiences reflected both unconventional and more traditional choices, and the view that women who give birth at home characteristically belong to the counterculture could not be justified. The findings of this study suggest that stereotypes of women who give birth at home do not apply to the circumstances of substantial numbers of women.

Adult↗
PubMed1991

Modulation by oxygen of the glucagon-dependent activation of the phosphoenolpyruvate carboxykinase gene in rat hepatocyte cultures.

In liver phosphoenolpyruvate carboxykinase (PCK) activity, protein and mRNA are localized predominantly in the periportal zone. The activation of the PCK gene by glucagon was studied in primary rat hepatocyte cultures under physiological arterial and venous oxygen tensions [16% and 8% (by vol.)]. PCK gene expression was monitored on the level of transcription, mRNA abundance and enzyme activity as well as enzyme synthesis and degradation. 1. Transcription of the PCK gene was increased by 10 nM glucagon maximally after 0.5 h; it reached nearly basal levels again after 2 h. The increase in transcription was 45% lower under 8% oxygen than under 16% oxygen. 2. PCK mRNA was maximally increased after 2 h under 16% oxygen and after 4 h under 8% oxygen; it subsequently declined to twice the basal values after 8 h. The maximal increase after 2 h was 50% lower under 8% oxygen than under 16% oxygen. 3. PCK enzyme activity was maximally increased after 4-6 h. The maximal enhancement after 4 h was 50% lower under 8% oxygen than under 16% oxygen. 4. The increase in PCK enzyme activity was due to an enhanced synthesis rate of PCK protein. The rate increased after 3 h was 35% lower under 8% oxygen than under 16% oxygen. 5. The degradation of PCK protein was equal under both oxygen tensions. The results show that in cultured rat hepatocytes the induction of PCK gene expression is modulated by physiological concentrations of oxygen. The modulation occurred at the level of gene transcription, mRNA abundance, enzyme protein synthesis and enzyme activity. The periportal to perivenous oxygen gradient could be the major factor responsible for the predominant expression of the PCK gene in the periportal zone.

Animals↗
PubMed1990

A murine even-skipped homologue, Evx 1, is expressed during early embryogenesis and neurogenesis in a biphasic manner.

Using the Drosophila even-skipped (eve) homeobox as a probe, we have isolated two murine genes, Evx 1 and Evx 2, from a genomic library. Evx 1, Evx 2, eve and the Xenopus Xhox-3 constitute a family of related genes based on similar homeodomain sequences. In addition, Evx 1 and Evx 2 share extended amino acid conservation outside of the homeobox. The Evx 1 protein consists of 416 amino acids as deduced from the longest open reading frame of Evx 1 cDNAs. Evx 1 is located 3.7 cM from the Hox 5 locus on mouse chromosome 2. It is expressed in undifferentiated F9 stem cells but not in cells differentiated with retinoic acid and cAMP. During embryogenesis, Evx 1 shows a biphasic expression pattern. From days 7 to 9 p.c. Evx 1 expression emerges at the posterior end of the embryo within the primitive ectoderm, and later in the mesoderm and neuroectoderm. From days 10 to 12.5 p.c. Evx 1 transcripts are restricted to specific cells within the neural tube and hindbrain along their entire lengths and coincides temporally, as well as spatially, with maturation of early forming interneurons, possibly commissural interneurons. The early and late transcription pattern is compatible with a role of Evx 1 in specifying posterior positional information along the embryonic axis similar to the Xenopus Xhox-3 and in specifying neuronal cell fates within the differentiating neural tube in analogy to eve in the embryonic central nervous system of Drosophila, respectively.

Amino Acid Sequence↗
PubMed1990

Molecular mechanisms of DNA damage initiated by alpha, beta-unsaturated carbonyl compounds as criteria for genotoxicity and mutagenicity.

alpha, beta-Unsaturated carbonyl compounds are important not only from a theoretical but also a practical standpoint. These ubiquitous compounds can interact with DNA through various mechanisms. The predominant interaction is the formation of cyclic 1,N2-deoxyguanosine adducts; 7,8-cyclic guanine adducts are also found. We have synthesized and characterized the stereoisomers of adducts formed by about 20 alpha, beta-unsaturated carbonyl compounds. The different types of adducts and the mutagenic and genotoxic response can be explained by the molecular structures of the agents. Compounds forming saturated cyclic adducts are mutagenic in S. typhimurium strain TA100 and to a lesser extent in TA1535. Substances with a leaving group at the C-3 position form unsaturated conjugated cyclic adducts and are mutagenic only in the His D3052 frameshift strains with an intact excision repair system (no urvA mutation). Metabolic epoxidation of the double bond and other metabolic activation, e.g., activation of the nitrogroups via nitroreductases, were also found to contribute to genotoxic and mutagenic activities. Our results have further elucidated the genotoxic mechanisms of these compounds; however, additional investigations are required for a complete understanding of the genotoxic activity of this class of compounds.

Acrolein↗
PubMed1989

[Results of surgical treatment of syndactylia of the hand].

The Syndaktyly is one of the most frequent failures of the hand. The aim of its operative treatment is a functional improvement of the developing hand and its aesthetics. The right moment and method of operation are decisive for the functional and aesthetics success as the kinds of Syndaktyly vary. Between 1970 and 1985 96 children have been operated on the hand because of Syndaktyly and its varieties at the Halle-Surgical-University-Hospital. Experiences and results during the treatments of this misdevelopment are being reported in a study of postoperative treatment over period of 15 years.

Child↗
PubMed1988

Regulation of the expression of the phosphoenolpyruvate carboxykinase gene in cultured rat hepatocytes by glucagon and insulin.

The induction of phosphoenolpyruvate carboxykinase (PEPCK) by glucagon was studied in primary rat hepatocyte cultures by determining the time course of the sequential events, increases in the enzyme's mRNA abundance, synthesis rate, amount and activity, and by investigating the antagonistic action of insulin on the induction by glucagon. 1. The mRNA of PEPCK was induced maximally 2-3 h after addition of 10 nM glucagon, as detected by Northern-blot analysis after hybridization with a biotinylated antisense RNA of PEPCK. 2. The synthesis rate of PEPCK increased maximally 2-3 h after application of glucagon as revealed by pansorbin-linked immunoprecipitation of [35S]methionine-labelled PEPCK. 3. The enzyme amount and activity was maximally induced 4 h after glucagon application. 4. The mRNA of PEPCK was half-maximally induced by 0.1 nM and maximally by 1 nM and 10 nM glucagon. The half-maximal induction by 0.1 nM glucagon was antagonized almost totally, and the maximal induction by 1 nM glucagon partially, while the maximal induction by 10 nM glucagon remained unaffected by 10 nM insulin. The results show that in cultured rat hepatocytes physiological concentrations of glucagon stimulated the induction of PEPCK by an increase in mRNA, that the glucagon-dependent increase in mRNA and enzyme-synthesis rate occurred in parallel and preceded the increase of enzyme amount and activity by 1-1.5 h, and that physiological levels of insulin antagonized the induction by glucagon in the physiological concentration range, with glucagon being the dominant hormone.

Animals↗