8 research outputs found
The averaged pressure-diameter curves for early-pregnant (solid lines) and term-pregnant women (dashed lines).
<p>The averaged pressure-diameter curves for early-pregnant (solid lines) and term-pregnant women (dashed lines).</p
Box-plots showing the pressure-strain elastic modulus of the uterine-near part, the middle part and the vaginal part of the uterine cervix for early and term-pregnant women.
<p>The plus whiskers display the upper values within 1.5 times the interquartile range beyond 75th percentile and the minus whiskers, display the minimum value. Difference in EP along the length of the cervix was found for the early-pregnant women.</p
Illustration of the probe in the uterine cervical canal.
<p>The tip of the probe is placed in the uterine cavity, with the middle two thirds of the probe in the cervical canal leaving 2–3 sensors visible outside the canal protruding into the vagina. The two gray lines represent the excitation electrodes whereas the 16 black sensors detect 16 cross-sectional areas along the probe.</p
The pressure-strain elastic modulus (EP) for the uterine-near part, the middle part and the vaginal part of the uterine cervix.
<p>Significant difference (one-way ANOVA) was found when comparing the three cervical parts for the early-pregnant women (p = 0.04) whereas axial variation was not found for the term-pregnant women (p = 0.88).</p
Validation data from testing in two phantoms.
<p>Each colored line represents the diameter data obtained from each sensor. The bag was inflated and deflated several times in a cylinder-shaped phantom with the diameter 20.8 mm (A) and in a funnel-shaped phantom with diameters ranging from 5–19 mm (B). The tracings demonstrate that the diameter measurements are accurate and reproducible.</p
Geometric and biomechanical properties of the uterine cervix of an early-pregnant woman (left column, A–D) and term-pregnant woman with an unripe cervix (right column E–H).
<p>A and E) Spatio-temporal diameter plots. The black line illustrates the volume of the bag (ml), the white line the pressure inside the bag (mmHg), and the colors spanning from blue to red illustrate the magnitude of diameters obtained in the measurement area. B and F) The cervical canal configuration generated at distension volume 2 ml (blue line) and 45 ml (red line). The black dots represent the internal and external cervical os of the uterine cervix. C and G) Pressure-diameter plot. The pressure-diameter relationship for three locations representing the uterus-near part (blue line), the middle part (red line), and the vaginal part (green line) of the uterine cervix. The black dots represent the linear part of the curve. D and H) Pressure-strain elastic modulus plot. The pressure-strain elastic modulus distribution along the cervical canal.</p
Three-Dimensional Polydopamine Functionalized Coiled Microfibrous Scaffolds Enhance Human Mesenchymal Stem Cells Colonization and Mild Myofibroblastic Differentiation
Electrospinning has been widely applied
for tissue engineering due to its versatility of fabricating extracellular
matrix (ECM) mimicking fibrillar scaffolds. Yet there are still challenges
such as that these two-dimensional (2D) tightly packed, hydrophobic
fibers often hinder cell infiltration and cell–scaffold integration.
In this study, polycaprolactone (PCL) was electrospun into a grounded
coagulation bath collector, resulting in 3D coiled microfibers with <i>in situ</i> surface functionalization with hydrophilic, catecholic
polydopamine (pDA). The 3D scaffolds showed biocompatibility and were
well-integrated with human bone marrow derived human mesenchymal stem
cells (hMSCs), with significantly higher cell penetration depth compared
to that of the 2D PCL microfibers from traditional electrospinning.
Further differentiation of human mesenchymal stem cells (hMSCs) into
fibroblast phenotype <i>in vitro</i> indicates that, compared
to the stiff, tightly packed, 2D scaffolds which aggravated myofibroblasts
related activities, such as upregulated gene and protein expression
of α-smooth muscle actin (α-SMA), 3D scaffolds induced
milder myofibroblastic differentiation. The flexible 3D fibers further
allowed contraction with the well-integrated, mechanically active
myofibroblasts, monitored under live-cell imaging, whereas the stiff
2D scaffolds restricted that
Re-Endothelialization Study on Endovascular Stents Seeded by Endothelial Cells through Up- or Downregulation of VEGF
We studied the effects of gene transfection
of endothelial cells with vascular endothelial growth factor (VEGF)
on re-endothelialization and inhibition of in-stent restenosis. Transfected
endothelial cells (ECs) exposed to different VEGF levels were seeded
on a stent surface for evaluation in vitro. VEGF<sub>121</sub><sup>++</sup> ECs and VEGF<sub>121</sub><sup>––</sup> ECs
were established using lentiviral-mediated HUVECs transfection. VEGF
RNA transcription level and VEGF protein expression were detected
by qPCR, Western blot, and ELISA. Methyl thiazolyl tetrazolium (MTT)
assay, wound healing assay, and in vitro HUVEC tube formation assay
showed that VEGF overexpression promoted cell proliferation, migration,
and endothelial capillary-like tube formation. Downregulation of VEGF
expression inhibited these activities. Using a rotational culturing
system, cells tightly adhered on the stent surface. Stents seeded
with transfected ECs at different VEGF levels were implanted in abdominal
aortas of New Zealand white rabbits to study re-endothelialization
and inhibition of in-stent restenosis. Stents with cells exposed to
excess VEGF expression were almost completely covered with cells after
stent implantation for 1 week (w). In the VEGF interference group
this process was delayed over 4 w due to RNAi-mediated silencing of
VEGF. Cryosectioning after 12 w showed that stents seeded with HUVECs
exposed to excess VEGF expression significantly reduced the neointima
area and stenosis when compared with bare metal stents and stents
from the VEGF interference group. Transgenic HUVECs were not found
in tissues of experimental animals. Furthermore, cells from these
tissues were similar to those from normal tissue. In conclusion, VEGF-mediated
endothelialization was found. Furthermore, ECs exposed to VEGF overexpression
reduced neointimal hyperplasia, promoted endothelialization, and reduced
in-stent restenosis