Browsing by Subject "Vascularization"

Now showing 1 - 3 of 3
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    Low-intensity pulsed ultrasound increased blood vessel size during fracture healing in patients with a delayed-union of the osteotomized fibula
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Korstjens, Clara M.; Rutten, Sjoerd; Nolte, Peter A.; van Duin, Marion A.; Klein Nulend, Jenneke
    Disturbed vascularity leads to impaired fracture healing. Since low-intensity pulsed ultrasound (LIPUS) increases new bone formation in delayedunions, we investigated whether LIPUS increases blood supply in delayed-unions of the osteotomized fibula, and if LIPUS-increased bone formation is correlated to increased blood supply. Blood vessel parameters were analysed using histology, immunohistochemistry, and histomorphometric analysis as well as their correlation with bone formation and resorption parameters. Fibular biopsies of thirteen patients with a delayed-union of the osteotomized fibula treated for 2-4 months with or without LIPUS originating from a randomized prospective double-blind placebo-controlled clinical trial were studied. In histological sections of the fibular biopsies parameters of blood vessel formation were measured and were related to histomorphometric bone characteristics of newly formed bone of the same samples analysed in our previously published study on the effects of LIPUS on bone healing at the tissue level in delayed-unions. LIPUS-treated delayed-unions and sham-treated delayed-unions as well as healed delayedunions and failed-to-heal delayed-unions were compared. The volume density of blood vessels was increased in LIPUS-treated delayed-unions compared to sham-treated controls. LIPUS did not change blood vessel number, but significantly increased blood vessel size. Healed delayed-unions as well as LIPUS-treated and sham-treated delayed-unions showed significant correlations between blood vessel size and osteoid volume. LIPUS increases blood vessel size, essential for fracture healing, in bone from patients with a delayedunion of the osteotomized fibula. The increased osteoid volume in delayed-unions can largely be explained by increased blood supply and perfusion.
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    Placental vascularization in in vitro-derived pigs: a preliminary study
    (Colégio Brasileiro de Reprodução Animal - CBRA, 2022-09) Úrsula Álvarez Martín; Pilar Coy; Juan Seva; Raquel Romar Andrés; Ester Párraga Ros; Fisiologia
    The placenta plays a critical role in maintaining and protecting the developing fetus. Placental vascularization abnormalities, including a decrease in arterial number, lumen size, and branching, have been extensively described in humans born from in vitro-produced (IVP) embryos (Riesche and Bartolomei, Seminars Reprod Med, 36:240-247, 2018) but studies on IVP pigs are very limited (Ao et al., Placenta 57:94-101, 2017). The objective of this study was to compare the placental vascularization in pigs born from in vitro- and in vivo-produced embryos (the latter born by artificial insemination; AI group). IVP embryos were produced after in-vitro fertilization (IVF) of in vitro matured oocytes and further culture (IVC) up to blastocyts stage in media supplemented with or without 1% porcine oviductal fluid and 1% uterine fluid (more details in Paris-Oller et al., J AnimSci and Biotech 12:32-44, 2021). Blastocysts produced with (RF-IVP group) and without (C-IVP group) reproductive fluids were surgically transferred at day 7 post-IVF. Both AI and IVP embryos were produced with spermatozoa from the same boar. After birth, placenta samples were collected at 3-5 cm from the insertion of umbilical cord, and fetal parameters were recorded. The placenta of 9 animals (3 per group) from different litters was selected following these criteria among animals: similar uterus position, birth weight, and crown-rump length; and a close male/female ratio among groups. Samples were fixed (10% formaldehyde solution) and paraffin embedded. Two complete placental sections (5 μm thickness) were stained (hematoxylin–eosin), photographed at 5x (ZEN 3.2, ZEN lite, Zeiss) and images processed (ImageJ) for a detailed study to record vessel number, area occupied by each vessel (µm2), and total vascular area (%). Based on their size and histological characteristics, vessels were categorized by an expert operator as capillary (1-500 µm2), arteriole/venule (501-1000 µm2), small artery/vein (1001-3000 µm2), medium-sized artery/vein (3001-30000 µm2), and large artery/vein (>30000 µm2). Data (mean±SEM) were analyzed by one-way ANOVA (Systat v13.1), and differences (P<0.05) were compared by Tukey’s test. The total placental area observed, and total number of vessels analyzed was higher in AI (86.1±7.5 mm2, 726 vessels) than C-IVP (45.9±6.8 mm2, 544 vessels), and RF-IVP (52.8±5.1 mm2, 637 vessels) (P<0.05). However, no differences were found in the total vascular area being 14.9±3.3% (AI), 19.9±2.7% (C-IVP), and 17.8±2.2 (RF-IVP) with similar pattern distribution in all groups: over 85% microvessels, 10-15% medium-size vessels and 5% macrovessels. However, the vascular area occupied by medium-sized vessels (arteries and veins) was significantly higher in the AI group (7.2±0.5%) than in IVP groups (2.1±0.3% and 1.8±0.2%) regardless of the addition of reproductive fluids (P<0.05). No differences in vascular areas of micro and macrovessels were observed. Preliminary results show that impaired placental vascularization in ART-derived pigs might occur due to a reduction of medium size vessels.
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    The impact of in vitro embryo production on placental and umbilical cord vascularization is minimized by the addition of reproductive fluids
    (Elsevier, 2023-09-15) Párraga Ros, Ester; Álvarez Martín, Úrsula; Seva Alcaraz, Juan; Coy, Pilar; Romar, Raquel; Anatomía y Anatomía Patológica Comparada
    Animals born from in-vitro-produced (IVP) embryos show changes in the placenta and umbilical cord vascularization. This study compares the placental and umbilical vascular morphometry in pigs (n = 19) born through artificial insemination (AI group) or after transfer of IVP embryos cultured with (RF-IVP group) or without (C-IVP group) reproductive fluids. The relationship between vascular parameters and animal growth during the first year of life was also analyzed. Samples were collected at birth, fixed, paraffin-embedded, cut in sections, stained, and photographed for vascular and morphometric analysis with ImageJ® and Slide Viewer®. The average daily weight gain was individually scored from birth to the first year of life. No differences were found in placental vascular morphometry among groups, except for the vascular area of small vessels (arterioles, venules, and small vessels) that was higher in the C-IVP group. Regarding the umbilical cord, the values for perimeter (AI: 26.40 ± 3.93 mm; IVP: 30.51 ± 4.74 mm), diameter (AI: 8.35 ± 1.01 mm; IVP: 10.26 ± 1.85 mm), area (AI: 43.18 ± 12.87; IVP: 56.61 ± 14.89 mm2), and Wharton's jelly area (AI: 36.86 ± 12.04 mm2; IVP 48.88 ± 12.80 mm2) were higher in IVP-derived than AI-derived animals, whereas arterial and venous morphometric data were similar between groups. A correlation study showed that placental and umbilical cord vascular phenotypes affect the further growth of pigs. In conclusion, assisted reproductive technologies impact small caliber vessels in the placenta and morphometric parameters in the umbilical cord. The addition of reproductive fluids in IVP-embryo contributes to reduce the differences with in vivo-derived animals.