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H Engelhardt

Publications and source records attributed to H Engelhardt.

At least 73 records · Page 4Linked to original sources
PubMed1979

BCG vaccination of neonates, infants, schoolchildren and adolescents. Part I: Dose finding studies with BCG strain 1331 Copenhagen.

A BCG vaccine prepared from strain 1331 Copenhagen was given to newborns and infants in four logarithmically decreasing doses (expressed in VU = viable units): 25 X 10(4), 11 X 10(4), 5 X 10 (4), and 2.2 X 10(4). The efficacy of the vaccine was determined through the conversion rate (tuberculin skin test) with 2 and 10 T. U. of RT 23, AND 10 AND 50 I. U. of GT (Hoechst). The results indicated that the conversion rate is a function of the dose of VU of the vaccine, as well as of the units of tuberculin used for testing.

Adolescent↗
PubMed1979

BCG vaccination of neonates, infants, schoolchildren and adolescents. Part II: Safety of a vaccine with strain 1331 Copenhagen.

The safety of the vaccine could be assessed by three different investigations: a) During the dose finding study (part I) the vaccine showed good safety in all concentrations employed concerning reactions at the site of injection; palpable lymph node enlargement was common. There was one case of suppurative lymphadenitis amond the 262 children who were given the vaccine in the highest concentration (25 X 10(4) VU). b) Subsequent trials in the course of 21 months, when high risk persons could be vaccinated, revealed a rate of this complication in the 1:1,000 range, no case was reported among older persons. c) After the official approval of the vaccine (10 - 30 X 10(4) VU/ml) in the FRG 1 supp. lymphadenitis among 5,000 vaccinated newborns can be calculated.

Adolescent↗
PubMed1978

[Investigations carried out to ascertain the dose-effect relationship of a BCG vaccine, strain 1331 Copenhagen, in neonates and young infants (author's transl)].

1405 neonates and infants were vaccinated with BCG Vaccine (strain 1331 Copenhagen) at five clinics in the Federal Republic of Germany. Doses in logarithmic increments from 22000 to 250000 VU (viable units)/0.1 ml were given by strictly intradermal injection. Carrying out the post-vaccinal tuberculin test by the MENDEL-MANTOUX technique, the dose-effect relationship could be demonstrated (Fig. 3). Conversion rates raised from 43% to 76% (Tab. 1); they are furthermore depending from the tuberculin dose and the assessment of the skin reaction. Tests with up to 50 I.U. of purified tuberculin were resulting in conversion rates over 90% for vaccination doses of 100 000 VU and more, any palpable infiltration regarding as a positive result (Fig. 4). The vaccine showed good safety in all concentrations employed concerning reactions at the site of injection. Lympnode enlargement, palable even 12 weeks postvacc., was common. In the course of the trial there was one case of suppurative lymphadenitis among the 262 children who were given the vaccine in the highest concentration (250000 VU). Subsequent trials revealed a rate of this complication in the 1:1000 range. The approval for the vaccine with 100000-300000 VU/dose has subsequently been given by the Federal Bureau for Sera and Vaccines.

BCG Vaccine↗
PubMed1976

Field trials with killed oral typhoid vaccines.

The article gives the results of the use of two types of killed oral typhus vaccine administered to students 10 to 19 years of age in two urban areas of the Province of Santiago. Vaccine from the German Democratic Republic (GDR) was administered to 37,517 students and placebo to an equivalent control group. The period of observation was 18 months (November 1973-April 1975). The other product, from the German Federal Republic (GFR) was administered to 37,566 students, with placebo given to an equivalent control group. In this case the observation period was 7 months (October 1974-April 1975). The antigenic composition of the two vaccines is qualitatively and quantitatively different as are the characteristics of their preparation. In the field trial with the product from the GDR, the morbidity for typhoid fever in the vaccinated and control groups showed statistically significant differences, even though on the border line level. Satisfactory and highly significant results had been obtained with the product in earlier field trials. The difference observed between morbidity in the two groups in the field trial with GFR vaccine was not significant. It is emphasized in this regard that the observation period was shorter in this case, which precludes definitive conclusions. A high proportion of reliable confirmation of diagnosis of cases is evident for both field trials. The findings show the need for subjecting this type of vaccine to further and better field trials.

Administration, Oral↗
PubMedDate not supplied

Application of a diode-array detector in capillary electrophoresis.

In the last decade diode-array detection has proved to be extremely useful in high performance liquid chromatography in recording UV-visible spectra directly and on-line in the column effluent. In capillary electrophoresis (CE) only fast-scanning detectors with long scan times (up to 2 s) are commercially available. A home-made CE instrument with a diode-array detector (DAD) was built and compared with a commercial fast-scanning detector. It is shown that the fast-scanning detector is advantageous when less than eight wavelengths are monitored. Due to the high data collection rate the DAD is superior if high resolution UV-visible spectra are acquired or if several spectra of a narrow peak (usual peak width in CE below 5 s) are needed for peak purity control. It is shown that DAD detection can help to develop separation methods, to identify peaks according to their UV-visible spectra, and to check peak purity.

Ascorbic Acid↗
PubMedDate not supplied

Electron microscopy of human erythrocyte catalase: new two-dimensional crystal forms.

Using the mica-spreading "negative staining-carbon film" procedure, human erythrocyte catalase has been shown to create a number of different periodic or crystalline two-dimensional (2-D) arrays which differ in the arrangement of molecules in the repeating units and the lattice type. Digital image processing has been performed with a 2-D array which contains regularly arranged "undulating" rows of molecules and also with a 2-D crystal form, exhibiting pgg (p22(1)2(1)) symmetry and lattice parameters of a = 12.7 nm, b = 44 nm, and gamma = 92 degrees. The data are compared with our previous analysis of a different human erythrocyte catalase 2-D crystal, and the effect of partial-depth negative staining occurring in all the various 2-D forms is discussed.

Catalase↗
PubMedDate not supplied

Topology of the anion-selective porin Omp32 from Comamonas acidovorans.

Limited proteolysis experiments were performed with outer membranes from Comamonas acidovorans to probe the topology of its major protein component, the anion-selective porin Omp32. Proteinase K treatment above a critical temperature of 42 degrees C cleaved the surface-exposed regions of the porin, yielding membrane-embedded fragments which were separated by SDS polyacrylamide gel electrophoresis or reversed phase chromatography. The identification of the proteinase K-sensitive sites was performed by microsequencing. This allowed us to determine six surface-exposed sites of the porin, all located in nonconserved primary structure regions. These results along with the previously determined amino acid sequence and in conjunction with some structural constraints applicable to porins allowed us to propose a chain-folding model of the Omp32 porin. The features of our model are compared with the structure of the Rhodobacter capsulatus porin, recently established by X-ray crystallography (Weiss et al., 1991) and they are used to elucidate the structural basis of the anion selectivity.

Amino Acid Sequence↗