Revistă de Medicină şi Farmacie - Clujul Medical - Iuliu Haţieganu

Patologie ginecologică
are different degrees of diferentiation from mesenchymal
cells to myofibroblasts. Human umbilical cord multipotent
mesenchymal stromal cells (UC-MSC) have recently
been identified as ideal candidate stem cells for cell-based
therapy [3,4,5].
In umbilical cord there are normally 2 arteries and
one vein. In some cases there is only one umbilical artery,
or local fusion of the two artery, or doubled umbilical vein
[6].
Human umbilical vessels differ in many ways from
the major vessels in the body.
Aspects of optical microscopy by the technique of
semifine sections
Aspects of optical microscopy in normal
pregnancy
Umbilical arteries consist of three layers: tunica
intima, tunica media and tunica adventitia, arranged
concentrically around the lumen (Fig. 1).
• The tunica intima: Endothelium is simple pavement
epithelium on a basal membrane [7]. It is made up of a
single row of cells, tightly joined together by intercellular
junctions. The apical pole of cells bulges into the vascular
lumen (Fig. 2). The absence of the internal elastic lamina
between the intima and the media, which is present in all
the arteries and arterioles of the other organs, which is
present in all the arteries and arterioles of the other organs,
is characteristic of the umbilical artery (Fig. 3).
Fig. 3. The absence of the internal elastic lamina.
• The tunica media: It is the thickest layer. It is
made up of smooth muscle fibers arranged concentrically
around the lumen. Between the smooth muscle fiber layers,
collagen and reticulin fibers are found, which join smooth
muscle fibers together, ensuring at the same time the
stability of this coat.
• The tunica adventitia: It is predominantly
composed of connective tissue, which contains collagen
fibers, fibrocytes and sometimes rare muscle fibers. The
adventitia is separated from the media by the external
elastic lamina, evidenced in microscopic preparations with
routine stains as a white thin band.
Aspects of optical microscopy in pregnancy
complicated by severe preeclampsia
• The tunica intima: Various endothelial changes
occur, evidenced by the presence of pyknotic cells or
cells with an altered structure, from which fragments are
detached and fall into the lumen, so that some epithelial
areas are destroyed, lacking endothelial cells (Fig. 4).
Fig. 1. Optical microscopy of the umbilical arteries.
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Fig. 2. The apical pole of endothelial cells bulges into the vascular
lumen.
Clujul Medical 2009 Vol. LXXXII - nr. 3
Fig. 4. Some epithelial areas are destroyed, lacking endothelial
cells.
• The tunica media: Marked interfibrillar edema is
seen in the media (Fig. 5). Interfibrillar spaces are large
and they contain numerous vacuolar formations, probably
of lipoprotein or predominantly lipid nature (Fig. 6). In
this context, muscle fibers are independent of one another,
consequently isolated, part of them being segmented,