Biomedical subjects

P Höpfl

Publications and source records attributed to P Höpfl.

9 recordsLinked to original sources

PubMed2000

A microarray enzyme-linked immunosorbent assay for autoimmune diagnostics.

In order to quantify autoantibodies in the sera of patients with autoimmune disease, we have created a microarray-based immunoassay that allows the simultaneous analysis of 18 known autoantigens. The microarrays contain serial dilutions of the various antigens, thereby allowing accurate determination of autoantibody titer using minimal amounts of serum. The assay is very sensitive and highly specific: as little as 40 fg of a known protein standard can be detected with little or no cross-reactivity to nonspecific proteins. The signal intensities observed from serial dilutions of immobilized antigen correlate well with serial dilutions of autoimmune sera. Miniaturized and highly parallelized immunoassays like these will reduce costs by decreasing reagent consumption and improve efficiency by greatly increasing the number of assays that can be performed with a single serum sample. This system will significantly facilitate and accelerate the diagnostics of autoimmune diseases and can be adapted easily to any other kind of immunoassay.

Antibodies, Antinuclear↗

PubMed1991

Psychrotrophic, lactic acid-producing bacteria from anoxic waters in Ace Lake, Antarctica; Carnobacterium funditum sp. nov. and Carnobacterium alterfunditum sp. nov.

Heterofermentative, lactic acid-producing, gram-positive, motile bacteria were isolated from the waters of Ace Lake, Antarctica. All strains produced virtually only L(+)lactic acid from D(+)glucose. D(--)-ribose was fermented to lactic, acetic, and formic acids, and ethanol. Cell walls contained meso-diaminopimaleic acid. The strains did not grow at 30 degrees C and were psychrotrophic. Whole cells contained 18:1 cis 9 as a major component of their fatty acids. At 20 degrees C, the strains grew better anaerobically than aerobically and all strains lacked catalase, oxidase and respiratory lipoquinones. DNA that coded for most of the 16S rRNA gene of one of the strains was amplified by the polymerase chain reaction and sequenced. The strain was phylogenetically most closely related to Carnobacterium mobile (Knuc = 0.0214). The isolates separated into two phenotypes. DNA/DNA homology studies determined on a representative from each phenotype showed low homology between the phenotypes (38 +/- 8%), and with Carnobacterium mobile (26 +/- 2%, 34 +/- 2%). Carnobacterium funditum sp. nov. produced acid from mannitol, trehalose, but not amygdalin. The G + C content of the DNA was 32-34%, and the Type strain is DSM 5970 (=ACAM 312). Carnobacterium alterfunditum sp. nov. produced acid weakly from amygdalin but not from mannitol trehalose. The G + C content was 33-34%, and the Type strain is DSM 5972 (=ACAM 313).

Anaerobiosis↗

PubMed1989

The 23S ribosomal RNA higher-order structure of Pseudomonas cepacia and other prokaryotes.

A 23S ribosomal RNA gene of Pseudomonas cepacia has been cloned and sequenced. A general higher-order structure model based on earlier published models has been derived from comparative analysis of 23S-like rRNAs of eubacteria, archaebacteria, organelles and eukaryotes. Differences between the previous models were carefully analyzed and controversial regions evaluated. Moderately large insertions and deletions have been found at new points in the secondary structure. The analysis of 50 published as well as unpublished 23S rRNA sequences provide additional proof for six of the seven previously suggested tertiary interactions within the 23S rRNA. P. cepacia is the first representative of the beta subgroup of the Proteobacteria phylum whose 23S rRNA has been sequenced. A tree reflecting evolutionary relationships of prokaryotes was constructed. The topology of this tree is in good agreement with the 16S rRNA tree.

Base Sequence↗

PubMed1988