Immune response to natural and recombinant antigens of Helicobacter pylori in patients with dyspeptic complaints.

Sera of 223 dyspeptic patients with endoscopic findings of nonulcer dyspepsia (72%), gastric ulcer (15%) and duodenal ulcer (13%) were tested for antibodies against Helicobacter pylori with an enzyme immunoassay and an immunoblot technique using lysates of Helicobacter pylori cells as antigen source. One hundred and fifty-one (68%) sera were found to be positive for Helicobacter pylori IgG with both methods; 5% of the positive results in the enzyme immunoassay were false-positive due to cross-reactions mainly of proteins with a molecular mass of 43-66 kDa. Since cross-reactivity not only reduces the diagnostic value of the immunoassay but also complicates evaluation of the immunoblot results, an attempt was made to overcome these problems by using specific purified recombinant proteins instead of the crude cell preparations as antigens. Of the commonly recognised immunogens of Helicobacter pylori, antibodies against a cell surface protein of 26 kDa, the small urease subunit (29 kDa) and the cytotoxin-associated protein (130 kDa) were identified as highly sensitive serological markers for inclusion in a recombinant antigen mixture for Helicobacter pylori screening. Only the cytotoxin-associated protein was confirmed to be an indicator immunogen for ulcerogenic strains. To assess the reliability of recombinant fragments of this protein in serological screening, the reactivity of antibody to purified fragments of the cytotoxin-associated protein was compared with that to the natural protein. A C-terminal recombinant fragment of 58 kDa showed results identical to those obtained with the natural protein and was thus considered to be an appropriate component of an antigen mixture for serological detection of Helicobacter pylori.

The uterus: in vitro MR-anatomic correlation of normal and abnormal specimens.

Magnetic resonance (MR) images of 12 fresh uterine specimens obtained with a high-resolution surface coil were correlated with findings on gross and microscopic pathologic examination. The uterine wall can be differentiated into three distinct zones: a central high-intensity zone, a junctional low-intensity band, and a peripheral medium-intensity area. Whereas the endometrium (basale and functionale) corresponded to the high-intensity zone, the myometrium correlated best with the combined width of the areas of low and medium signal intensity. The signal intensity of a leiomyoma varied, depending on its cellularity. Primary endometrial and cervical carcinomas were clearly shown on MR images, as were other abnormalities such as adenomyosis and Nabothian cysts. The potential usefulness of MR imaging in detecting and staging uterine neoplasms is discussed.