Mean weighted nuclear volumes in colonic adenocarcinomas. Evaluation of prognostic significance.

OBJECTIVE: To investigate the correlation of stereologically estimated mean weighted nuclear volumes of tumor cell nuclei (MWNV) with other prognostic factors and survival in colonic adenocarcinomas. STUDY DESIGN: The study group consisted of 42 patients with colonic adenocarcinomas who were treated by a standardized protocol and had a mean follow-up of 89 months. The point sample intercepts method was used to estimate MWNV. In addition, immunohistochemical expression of p53 and Ki-67 was evaluated semiquantitatively. RESULTS: The calculated nuclear volumes correlated significantly with histologic grading and with the extent of tumor progression (organ confined/nonorgan confined). There was no correlation with p53 expression or proliferative activity determined by MIB-1 positivity. No correlation could be demonstrated with sex, age or clinical outcome of the patients. CONCLUSION: Assessment of MWNV in colonic adenocarcinomas does not provide additional information concerning the clinical course.

DNA-ploidy analysis correlates with the histogenetic classification of thymic epithelial tumours.

The ploidy values of the epithelial component were determined in a series of thymomas and organotypic thymic carcinomas using image cytometry and the results were compared with the histological tumour subtypes according to the histogenetic classification introduced by Marino, Müller Hermelink, and Kirchner (MMHK). Forty-six cases of thymic epithelial tumours were included in the study. After reclassification according to the MMHK classification, the distribution among the subtypes was as follows: three medullary, nine mixed type, five predominantly cortical (organoid), 16 cortical thymomas, and 13 well-differentiated thymic carcinomas. Single cell preparations were made from paraffin-embedded tumour tissue and stained according to Feulgen. Ploidy analysis was performed using an automated image analysis system. In five cases, DNA cytometry could not be performed, for technical reasons. The remaining 41 cases consisted of 11 diploid and 30 non-diploid tumours. The percentage of aneuploid tumours in the different subtypes increased from medullary (0 per cent) through mixed type (44.4 per cent), predominantly cortical (75 per cent), cortical (83.3 per cent) to well-differentiated thymic carcinomas (100 per cent). DNA-ploidy determination using image cytometry correlates with the concept of the MMHK classification of thymomas.

[Experimental evaluation of contrast medium enhanced high resolution MR angiography in the animal model. Gd-DTPA compared with Gd-DTPA-polylysine]. / Experimentelle Evaluierung der kontrastmittelverstärkten, hochauflösenden MR-Angiographie am Tiermodell. Gd-DTPA gegenüber Gd-DTPA-Polylysin.

PURPOSE: To evaluate the qualitative and quantitative efficacy of Gd-DTPA and Gd-DTPA polylysine for contrast-enhanced high resolution MRA (CMRA) of the abdominal vessels. MATERIALS AND METHODS: In ten anesthesized rabbits (average weight 4.3 kg) MR angiography was performed using a 1.5 T MR unit (Magnetom SP 63; Siemens Erlangen) and a CP head coil. Arterial MRA (FISP 3D TONE, TR/TE = 33/8, Flip 20 degrees) and venous MRA (FLASH 2D, TR/TE = 37/10, Flip 60 degrees) was performed before and after administration of the paramagnetic contrast agents Gd-DTPA (n = 5) or Gd-DTPA polylysine (n = 5) at a dosage of 0.1 mmol/kg. In all studies the single sections and the MIP reconstructions were evaluated quantitatively by measuring and calculating signal intensity, percentage enhancement, signal-to-noise and contrast-to-noise ratios. All studies were assessed qualitatively for visualization and distinction of the arterial and venous vessel system by three independent observers before and after the administration of contrast agent. RESULTS: Gd-DTPA-enhanced arterial FISP 3D tone led to a percentage enhancement of 30% for the kidneys, 12% for the superior mesenteric artery, 18% for the deep circumfluent iliac artery, and 7% for the internal iliac artery. In FLASH 2D sequences Gd-DTPA led to a good C/N only for venous abdominal vessels like the left renal vein (2.59) and internal iliac vein (1.66); the percentage enhancement of these structures was between 16 and 21%. Qualitative comparison also showed no significant improvement after injection of Gd-DTPA. In FISP 3D TONE sequences Gd-DTPA polylysine led to a strong percentage enhancement of right and left kidney (21 and 40%) and deep circumfluent iliac artery (17%). Qualitative evaluation showed improved delineation and contrast of low-diameter vessels, while the soft tissue was only slightly enhanced and did not impair vessel visualization. CONCLUSION: CMRA using Gd-DTPA and Gd-DTPA polylysine significantly improved the delineation of abdominal vessels, with Gd-DTPA polylysine being superior.

[Contrast medium enhanced MR angiography]. / Kontrastmittelunterstützte MR-Angiographie.

Magnetic resonance angiography (MRA) protocols are based on standard sequence protocols like time of flight MRA, which evaluates inflowing spins. This technique is limited by a variety of artifacts like the saturation artifact via turbulent blood flow. Contrast media diminish these artifacts like extracellular agents and blood-pool contrast media. The clinical value of the contrast-enhanced MRA for cerebral pathologies is based on the use of the paramagnetic contrast agent Gd-DTPA. For extracerebral diseases this technique is restricted because of the simultaneous visualization of both arterial and venous vascular territories. Occult venous sinus thrombosis or AV malformations are clinical essential indications for the use of C-MRA. Experimental data prove the excellent contrast abilities of blood-pool agents like Gd-DTPA-polylysin or Gd-DTPA-albumin, which demonstrate long intravascular persistence and retarded excretion.

[Gliadin IgA antibodies in diagnosis of celiac disease in childhood]. / Gliadin-IgA-Antikörper bei der Zöliakie-Diagnostik im Kindesalter.

An enzyme immunoassay kit for the determination of anti-gliadin-IgA antibodies in serum has been evaluated in the diagnosis of coeliac disease in childhood. 84 patients, 22 of them with coeliac disease according to ESPGAN's criteria were tested between 1978 and 1989 and the results have been correlated with the findings on small intestine biopsy and the clinical features. The sensitivity of the test was 95.5% and the specificity was 87.0% on initial diagnosis. On a gluten-free diet reduced antibody levels were seen in all patients. During gluten challenge 11 of 13 children showed an increase in anti-gliadin-IgA concentration. Of the remaining 2 without antibody elevation IgA deficiency became manifest in one patient, the other had a nearly normal mucosa on small intestine biopsy. Provided that IgA deficiency is ruled out and the gluten intake is sufficient the test seems to be useful for screening and might replace biopsy after gluten challenge in cases of increasing antibody levels.

Some methodic aspects in optimizing the radioimmunoassay of beta-endorphin.

A specific double antibody radioimmunoassay (RIA) for human beta-endorphin (beta-EP) using an antibody to synthetic beta h-endrophin was established. This antibody cross-reacted with beta-Lipotropin (beta-LPH) at 42 per cent on molar basis and allowed a usable range of 20 pg to 4 ng of beta-endorphin per ml in the assay. Comparing the efficiency of the conventional extraction procedures under various conditions using Corning glass, Vycor glass, QUSO G-32, silicic acid and controlled pore glass 75, the optimal result was obtained by Corning glass, with a recovery rate of more than 80 per cent. The most simple and rapid method with an extraction efficiency of more than 90 per cent was found to be the extraction by use of Sep-Pak C18 cartridges. The separation of beta-endorphin from beta-LPH was studied using Sephadex G-50, G-75, G-100 and Bio-Gel P-60 columns and different elution media. The use of a Sephadex G-50 column (0.9 X 55 cm) and elution with 0.1 N acetic acid-0.05 per cent HSA gave the best result. The reliability of the radioimmunoassay was shown under physiological and pathophysiological conditions.