Biomedical subjects

E M Marres

Publications and source records attributed to E M Marres.

5 recordsLinked to original sources

PubMed2000

Analysis of three-dimensional architecture in Feulgen-stained fine-needle liver aspirates, using confocal scanning laser microscopy.

Early and accurate diagnosis of hepatocellular carcinoma in liver nodules using fine-needle aspiration biopsy can still pose difficulties, particularly in cirrhotic nodules containing dysplastic hepatocytes. Loss of architectural clues, which may aid diagnosis, can be overcome by using confocal scanning laser microscopic examination of tissue fragments in smears without the need for further processing of slides. The basic fuchsin of the Feulgen method resulted in excellent confocal images without the need for further processing of the smears. Clear morphological differences in three-dimensional reconstructions of optically sectioned tissue fragments were demonstrated in normal, hyperplastic, and malignant smears as an aid to diagnosis.

Biopsy, Needle↗

PubMed1998

Combining QUANTICYT karyometric analysis with architectural confocal-aided cytology to prognosticate superficial bladder cancer.

For this study, bladder washings of 923 patients with a follow-up for superficial bladder cancer were used. For the prognostication of each case (follow-up period up to 20 mo), two parameters were used: tumor recurrence and the event of (progressing) invasive growth. Each sample was classified as negative, low grade or high grade, based on confocal-aided architectural cytology. The feature architecture was based on the images of the epithelial fragments as seen in the Feulgen stain, which also could be visualized in confocal microscopy. The same three classes were also used for grading the samples according to the QUANTICYT system, in which DNA and morphometry of nuclei were automatically assessed. The 532 cases graded as QUANTICYT high had a worse prognosis than the 391 cases with QUANTICYT low. In addition, architectural cytology contributed significantly for the prognostication of cases classified as QUANTICYT high, the 228 nonconcording cases faring better than the 304 concording ones. For QUANTICYT low, the 156 nonconcording cases had also a lower recurrence rate than the 235 concording ones, but this difference was only significant in patients followed for up to 8 mo. These findings indicate that QUANTICYT grading supplemented by architectural cytology supplies the clinician with valuable prognostic information which can be used to limit cystoscopies.

Automation↗

PubMed1998

Microwave-stimulated Jones-Marres method for staining fungi in brain tissue of immunocompromised patients.

Life-threatening fungal infections have increased significantly in the past decade due to the rising number of immunocompromised patients. Serological diagnosis of most fungal infections is unreliable and blood cultures are positive in only 50% of premortem cases; therefore, tissue sampling together with fast, reliable staining of fungi should be carried out to reach the correct, timely diagnosis. We developed, partly serendipitously, a microwave silver staining method for fungi in histological sections. During a differentiation step in periodic acid, background staining is removed. This rapid staining method can be combined with immunostaining, for example, the alpha smooth muscle actin method, to visualize blood vessels. Silver staining results were optimized using the recently developed MicroMED BASIC microwave labstation for histology (Milestone srl, Italy), featuring no-touch temperature measurements and PC control.

Aspergillosis↗

PubMed1998

Visualization of vaginal flora in cervical smears using a modified microwave silver-staining method.

The advantage of studying the vaginal flora to determine the bacteria and fungi present in cervical smears (as opposed to cultivation of these micro-organisms) is that the micro-organisms can be observed in their natural habitat. However, they are only faintly stained by the conventional Papanicolaou method. Accordingly, contrast is weak and visualization poor. For this reason, we developed a modified microwave silver-staining method that can be performed retrospectively on stained smears. Bacteria and fungi stain distinctly black and can be studied in greater detail, and their inter-relationship can be visualized. Haematoxylin or Eosin counterstain allows us to visualize vaginal inhabitants in relation to epithelial cells. In the series presented here, we show that a modified microwave silver-staining method is well suited to studying the ecology of micro-organisms in smears taken from women presenting to their doctor with clinical symptoms. Using this staining method, we have shown that lactobacilli overgrowth is associated with symptoms.

Actinomyces↗

PubMed1994

Chemical and physical properties of collagen implants influence their fate in vivo as evaluated by light and confocal microscopy.

Porcine collagen membranes having a rough and a smooth side were used for subcutaneous implantation studies in rats. Two tanning protocols were used for the membranes, a new one involving microwaving and glutaraldehyde treatment (NEWGA), and the other, a conventional method using glutaraldehyde treatment at room temperature (OLDGA). Untreated membranes (NONGA) were also implanted. Sections of the implants were examined by light microscopy and with the confocal laser scanning microscope focusing on neovascularization and incorporation of the implant. At 64 days, the smooth sides of NEWGA and OLDGA implants were not well incorporated, with scarring subjacent to the surface and dystrophic calcification of that side of the membrane. At the same time, the rough sides of the NEWGA and OLDGA were not calcified with a giant cell reaction around the porcine collagen. The best incorporation was found in the NONGA membranes with no dystrophic calcification, excellent neovascularization of all layers, and complete remodeling at day 64. After 5 months, the completely remodeled NONGA membrane still could be identified, and the NEWGA and OLDGA membranes were calcified with a giant cell reaction having a dense fibrous capsule. It is concluded that if cross-linking is deemed necessary, the microwave cross-linking method is advisable because in the early stages there is less reactive inflammation around it, and the implant surfaces should be rough with an open structure, making calcification of cross-linked collagen unlikely.

Cell Differentiation↗