86 research outputs found
Angioleiomyoma of the small intestine – a rare cause of gastrointestinal bleeding
<p>Abstract</p> <p>Background</p> <p>Benign tumors are a rare cause of gastrointestinal hemorrhage of which angioleiomyomas constitute a very small minority. They have been reported in literature to present with volvulus, bleeding or intussusceptions.</p> <p>Case presentation</p> <p>An interesting case of a patient presenting with gastrointestinal bleeding from an underlying angioleiomyoma is discussed along with its management options.</p> <p>Conclusion</p> <p>Angioleiomyoma though rare can be managed successfully by surgical and/or minimally invasive endovascular procedures.</p
Intrinsic differentiation potential of adolescent human tendon tissue: an in-vitro cell differentiation study
BACKGROUND: Tendinosis lesions show an increase of glycosaminoglycan amount, calcifications, and lipid accumulation. Therefore, altered cellular differentiation might play a role in the etiology of tendinosis. This study investigates whether adolescent human tendon tissue contains a population of cells with intrinsic differentiation potential. METHODS: Cells derived from adolescent non-degenerative hamstring tendons were characterized by immunohistochemistry and FACS-analysis. Cells were cultured for 21 days in osteogenic, adipogenic, and chondrogenic medium and phenotypical evaluation was carried out by immunohistochemical and qPCR analysis. The results were compared with the results of similar experiments on adult bone marrow-derived stromal cells (BMSCs). RESULTS: Tendon-derived cells stained D7-FIB (fibroblast-marker) positive, but α-SMA (marker for smooth muscle cells and pericytes) negative. Tendon-derived cells were 99% negative for CD34 (endothelial cell marker), and 73% positive for CD105 (mesenchymal progenitor-cell marker). In adipogenic medium, intracellular lipid vacuoles were visible and tendon-derived fibroblasts showed upregulation of adipogenic markers FABP4 (fatty-acid binding protein 4) and PPARG (peroxisome proliferative activated receptor γ). In chondrogenic medium, some cells stained positive for collagen 2 and tendon-derived fibroblasts showed upregulation of collagen 2 and collagen 10. In osteogenic medium Von Kossa staining showed calcium deposition although osteogenic markers remained unaltered. Tendon-derived cells and BMCSs behaved largely comparable, although some distinct differences were present between the two cell populations. CONCLUSION: This study suggests that our population of explanted human tendon cells has an intrinsic differentiation potential. These results support the hypothesis that there might be a role for altered tendon-cell differentiation in the pathophysiology of tendinosis
Programmed cell death in nodular palmar fibromatosis (Morbus Dupuytren)
The regular loss of cellularity during
involutional phase of nodular palmar fibromatosis
(Morhus D~lp~lyt r enin)d icates a regulated process
known as programmed cell death (apoptosis).
Using the TUNEL method apoptosis-related DNA
fragmentation is detected in numerous cells as a
characteristic feature of fibromatosis noduli of
involutional phase. By means of double labelling
technique. a-smooth muscle actin immunohistochenlistry
and TUNEL method for apoptosis, i t is
demonstrated that the cells which underwent apoptotosis
are myofibroblasts. As anticipated, the antidote to
apoptosis bcl-2 is not detected in involutional phase, but
neither it is evidenced in proliferative phase. Immunohistochemically,
FasIAPO-l is shown to be existent in a
very small number of fibroblasts in involutional phase.
However. in view of the high number of TUNEL-stained
cells a significance in regulating apoptosis in nodular
palmar fibromatosis seems improbable.
Taking into account that the development of the
fibromatosis noduli, the expression of myofibroblast
phenotype, basement membrane formation and growth
factor expression including TGFD culminates in
involutional phase the initiation of apoptotic cell death
can be discussed in relation to these growth factors and
matrix protein action and the programmed cell death may be considered as the final step of myofibroblast
phenotype evolution
Laminin matrix formation and S-1 00 protein andlor desmin-positive cells in malignant fibrous histiocytoma MFH
16/30 human storiform-pleomorphic
malignant fibrous histiocytomas (MFH) showed a focal
pericellular immunostaining for laminin. 14/16 of these
laminin-positive tumours additionally revealed an
atypical cellular differentiation (desmin- andlor S- 100
protein-positive cells). The significance of focal laminin
positivity along with atypical, non-entity specific
differentiated cells is discussed before the background of
laminin as being an indicator and promoter of
differentiation in MFH. The limited value of a laminin
detection in MFH for solving differential diagnostic
questions (MFH versus other poorly differentiated
sarcomas with basement membrane formation) has been
pointed out
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