PubMed · 17218496
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Constance Holden. 2007-01-12. Stem cells. Versatile stem cells without the ethical baggage?. https://doi.org/10.1126/science.315.5809.170
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OBJECTIVE: Our aim was to determine whether a borderline amniotic fluid index observed during antepartum testing confers a significant risk of adverse perinatal outcome. METHODS: Between April 2001 and May 2005, uncomplicated gestations with a singleton non-anomalous fetus, who underwent weekly monitoring of amniotic fluid index (AFI) until delivery during the last trimester and who gave birth at our hospital, were identified for our study. Normal amniotic fluid volume and borderline amniotic fluid were defined as AFI of >10 and <24 cm and >5 and <10 cm, respectively. The groups were compared on maternal data, mode of delivery and perinatal outcomes such as fetal distress, intrauterine growth restriction and meconium fluid. RESULTS: A total of 90 cases were identified as borderline amniotic fluid and 277 cases as normal AFI. We observed significant increased incidences of admission to neonatal intensive care unit, intrauterine growth restriction, meconium-stained amniotic fluid, intrapartum fetal distress in the group with borderline amniotic index (P < 0.05). CONCLUSIONS: A borderline amniotic fluid index observed in antepartum testing during the last trimester carries an increased risk of adverse perinatal outcomes. These patients should be followed up carefully during the antepartum and intrapartum period.
Stem cells capable of differentiating to multiple lineages may be valuable for therapy. We report the isolation of human and rodent amniotic fluid-derived stem (AFS) cells that express embryonic and adult stem cell markers. Undifferentiated AFS cells expand extensively without feeders, double in 36 h and are not tumorigenic. Lines maintained for over 250 population doublings retained long telomeres and a normal karyotype. AFS cells are broadly multipotent. Clonal human lines verified by retroviral marking were induced to differentiate into cell types representing each embryonic germ layer, including cells of adipogenic, osteogenic, myogenic, endothelial, neuronal and hepatic lineages. Examples of differentiated cells derived from human AFS cells and displaying specialized functions include neuronal lineage cells secreting the neurotransmitter L-glutamate or expressing G-protein-gated inwardly rectifying potassium channels, hepatic lineage cells producing urea, and osteogenic lineage cells forming tissue-engineered bone.
PURPOSE: Wound healing of the cryo-injured bladder can bring about organ remodeling because of incomplete reconstitution of depleted smooth muscle cells. Stem cell transplantation could be beneficial to improve smooth muscle cell regeneration and/or modulate the remodeling process. The repair of bladder injury using adult-type stem cells would be useful for adult urological patients but unsuited for neonatal patients, in whom major benefits are likely to derive from fetal-type stem cells. MATERIALS AND METHODS: The smooth muscle cell differentiation potential of fetal-type vs adult-type stem cells was evaluated by injecting green fluorescent protein labeled mesenchymal stem cells from rat amniotic fluid or bone marrow, respectively, in cryo-injured rat bladder walls. RESULTS: At 30 days after transplantation only a few fetal-type or adult-type mesenchymal stem cells gave rise to enteric or vascular smooth muscle cells, whereas most mesenchymal stem cells appeared incapable of specific differentiation. In vitro co-culture experiments of smooth muscle cells with fetal-type or adult-type mesenchymal stem cells selectively labeled with distinct fluorochromes showed the presence of hybrid cells, suggesting that some mesenchymal stem cells can undergo cell fusion. Surprisingly the major effect of rat bone marrow or amniotic fluid mesenchymal stem cell transplantation seemed to be preventing cryo-injury induced hypertrophy of surviving smooth muscle cells. CONCLUSIONS: In this model stem cell transplantation has a limited effect on smooth muscle cell regeneration. Instead it can regulate post-injury bladder remodeling, possibly via a paracrine mechanism.