Biomedical subjects

E Höhne

Publications and source records attributed to E Höhne.

9 recordsLinked to original sources

PubMed1990

[In situ fluoride uptake of initial caries lesions following application of two children's toothpastes].

Cylindrical blocks of enamel with initial caries lesions were brushed twice a day for 6 days using amine fluoride or monofluorophosphate children's toothpaste (250 ppm F-). Some of the enamel samples were left in the oral cavity for three further days after the end of the trial, during which time a fluoride-free toothpaste was used for daily oral hygiene. Half of the enamel blocks showed plaque formation during this period. The other half were kept clean. Fluoride soluble in KOH was only detected on the enamel blocks that had been brushed with amine fluoride children's toothpaste. The amount of solidly bound fluoride was significantly higher following the use of amine fluoride children's toothpaste than with monofluorophosphate children's toothpaste. The amounts of KOH-soluble fluoride and solidly bound fluoride fell again 3 days after discontinuation of fluoride application. But only the drop in the amount of KOH-soluble fluoride in demineralised tooth enamel after application of the two children's toothpastes can be explained by the differing reaction mechanisms of the two fluoride compounds.

Dental Enamel↗

PubMed1989

Molecular mechanics and X-ray crystal structure investigations on conformations of 11 beta substituted 4,9-dien-3-one steroids.

The influence of 11 beta-phenyl substitution upon 4,9-dien-3-one steroid-backbone conformations is calculated by means of the MM2p molecular mechanics scheme. In the case of steroids having a 13 beta configuration, the lowest strain energy is always evaluated for the conformational combination of rings A(inverted) B(normal) while, moreover, the 11 beta substitution increases the relative stability of the conformation A(normal) B(normal) compared to the nonsubstituted compound. Introduction of the 11 beta substituent causes some bowing of the energy-minimum structures in the A-ring region toward the beta side. For 13 alpha configurated steroids, the ring conformations A(inverted) B(normal) C(boat) and A(normal) B(inverted) C(twist/boat) are found to be energetically preferred. Quantitative description of different ring conformations using asymmetry and pseudorotational parameters as well as the comparison of molecular mechanics and available X-ray structure data give an impression of the conformational mobility. Whereas the effect of 11 beta substitution within a given ring conformation is limited, contributions to molecular flexibility can be found in the ability to adopt different basic conformations and in the occupation of near-minimum structures. An X-ray crystal structure analysis of a potential antiprogestational steroid has been performed, and the results are in good agreement with the calculated structure.

Crystallography↗

PubMed1988

X-ray studies on piroxicam modifications.

The anti-inflammatory drug piroxicam, 4-hydroxy-2-methyl-N-(2-pyridyl)2H-1,2- benzothiazine-3-carboxamide-1,1-dioxide, crystallizes in three different forms, two anhydrates and one monohydrate. Crystal structure analyses of the monohydrate and one of the anhydrate were carried out by Bordner et al. and Kojić-Prodić et al., respectively. In this paper the results of the analysis of the third piroxicam modification and of an independently performed structure determination of the monohydrate are reported. Molecular structures and hydrogen bonding of all modifications are discussed.

Chemical Phenomena↗

PubMed1982

[Immunity against poliomyelitis in mothers and their newborn infants. Comparison of Hamburg and Bamako (Mali)].

The polio neutralisation test was performed in 199 paired sera from mothers and their newborn infants from the Hamburg area and in 69 paired sera from Bamako (Mali). Antibodies against all 3 poliovirus types were demonstrated in 52.3% of Hamburg and in 78.0% of bamako mothers. The significantly inferior protection of Hamburg mothers was caused by a lower rate of polio 3 antibodies. Only 65.3% of the Hamburg mothers had polio 3 antibodies in contrast to 88.0% of Malian mothers. Newborn infants from Hamburg had significantly higher polio 2 antibody titres than their mothers, newborn infants from Bamako in contrast had significantly lower polio 2 and 3 antibody titres than their mothers. Both groups share an insufficient transferral of polio 3 antibodies. When only titres outside the range of error of the neutralisation test (1 titre step) are considered as different, all 3 polio types in both groups show agreement of titres in mother and child in more than 90%.

Antibodies, Viral↗

PubMed1979