Search PubMed⌕ Search

Biomedical subjects

H Riegler

Publications and source records attributed to H Riegler.

5 recordsLinked to original sources
PubMed2005

Spreading and two-dimensional mobility of long-chain alkanes at solid/gas interfaces.

Long-chain n alkanes on solid surfaces can form partially wetting liquid alkane droplets coexisting with solid multilayer terraces. We propose a diffusivelike alkane flow between terrace edge and droplet perimeter through a molecularly thin "precursorlike" film. Depending on the (uniform!) sample temperature, either droplet or terrace edge are not in thermodynamic equilibrium. This leads to a chemical potential gradient, which drives the reversible alkane flow. The gradient can be adjusted and calculated independently from the phenomenological diffusion coefficient.

Journal Article↗
PubMed1991

Expression of a human monoclonal anti-HIV-1 antibody in CHO cells.

The cDNA coding for the light and heavy chains, respectively, of the human monoclonal antibody 3D6 (IgG1, kappa), which binds specifically to human immunodeficiency virus-1 (HIV-1) gp41, was inserted into three different mammalian expression vectors and transfected into Chinese hamster ovary (CHO) cells. Transcription was under the control of Rous sarcoma virus long terminal repeat (RSV LTR), human cytomegalovirus major immediate early (CMV IE) promoter, and mouse mammary tumor virus long terminal repeat (MMTV LTR), respectively. Antibody productivity was monitored in the supernatants of selected clones. The binding characteristics of the CHO-derived antibody to HIV-1 gp41 were found to be identical to that of the original antibody produced by hybridoma cells.

Animals↗
PubMed1987

Language training for generalization.

This paper presents a classroom-based language intervention program for preschool children with language delays or deficits. A major goal of the program is to ensure that children acquire missing skills through daily speech therapy and that they actively generalize these skills from therapy times to other classroom activities. This paper presents data collected with two children during daily speech therapy sessions and daily play activities. Instances in which the children generalized new language acquired in therapy to play activities will be discussed as well as instances in which the children failed to generalize new language. In addition, the influence of peer and teacher language usage on children's language production will be discussed. Finally, recommendations to enhance generalization of language skills within and across school settings will be presented.

Child↗
PubMedDate not supplied

Pulmonary surfactant protein C containing lipid films at the air-water interface as a model for the surface of lung alveoli.

The pulmonary surfactant lines as a complex monolayer of lipids and proteins the alveolar epithelial surface. The monolayer dynamically adapts the surface tension of this interface to the varying surface areas during inhalation and exhalation. Its presence in the alveoli is thus a prerequisite for a proper lung function. The lipid moiety represents about 90% of the surfactant and contains mainly dipalmitoylphosphatidylcholine (DPPC) and phosphatidylglycerol (PG). The surfactant proteins involved in the surface tension adaption are called SP-A, SP-B and SP-C. The aim of the present investigation is to analyse the properties of monolayer films made from pure SP-C and from mixtures of DPPC, DPPG and SP-C in order to mimic the surfactant monolayer with minimal compositional requirement. Pressure-area diagrams were taken. Ellipsometric measurements at the air-water interface of a Langmuir film balance allowed measurement of the changes in monolayer thickness upon compression. Isotherms of pure SP-C monolayers exhibit a plateau between 22 and 25 mN/m. A further plateau is reached at higher compression. Structures of the monolayer formed during compression are reversible during expansion. Together with ellipsometric data which show a stepwise increase in film thickness (coverage) during compression, we conclude that pure SP-C films rearrange reversibly into multilayers of homogenous thickness. Lipid monolayers collapse locally and irreversibly if films are compressed to approximately 0.4 nm2/molecule. In contrast, mixed DPPG/SP-C monolayers with less than 5 mol% protein collapse in a controlled and reversible way. The pressure-area diagrams exhibit a plateau at 20 mN/m, indicating partial demixing of SP-C and DPPG.(ABSTRACT TRUNCATED AT 250 WORDS)

Air↗