The regulation of trophoblast invasion and decidual reaction by matrix metalloproteinase-2, metalloproteinase-7, and metalloproteinase-9 expressions in the rat endometrium.

PURPOSE: We aimed to evaluate how matrix metalloproteinases (MMPs) regulate the trophoblast invasion and placentation. METHODS: Female rats were divided into the estrous cycle and early pregnancy day groups. Obtained uterine tissues and implantation sites were processed for immunofluorescence and real-time PCR examinations. RESULTS: The mRNA expression of MMP-7 was higher than MMP-2 and MMP-9. Immunofluorescence findings confirmed that MMP-2, MMP-7, and MMP-9 were localized in the endometrial stroma, while MMP-7 was high in glandular and lining epithelial cells throughout the entire estrous cycle. However, their immunolocalizations and mRNA expressions were dramatically changed with the early pregnancy days. The MMP-7 reached very strong immunostaining in the giant trophoblast cells (GTCs), and the cytoplasm of mature and differentiating decidual cells, whereas MMP-2 and MMP-9 were mostly seen in the primary decidual zone (PDZ), GTCs, and the endothelium of blood vessels. CONCLUSIONS: All three MMPs seemed likely to be a key mediator of trophoblast invasion into the decidual region as well as angiogenesis during the placentation process. Due to the strong and wide expression of MMP-7 in the mature decidua, it could be suggested that MMP-7 is important for decidual ECM remodeling and it might be used as a new marker of decidual reaction.

An easy, rapid, and reproducible way to create a split-thickness wound for experimental purposes.

Partial-thickness wound models of rat skin have some difficulties in creating the wounds in equal size and depth. Moreover, making a split-thickness wound on the rat skin seems not to be simple and rapid. A new alternative method was presented here to overcome these obstacles, by using a waterjet device to create a split-thickness wound on rat skin. Twenty-four male Wistar rats were randomly divided into 3 groups. An area of 4 × 4 cm in diameter was marked on the center of the dorsal skin. Waterjet hydrosurgery system was used to create a wound on the dorsal rat skin, by removing the outer layers of the skin. In group 1, rat skin was wounded with setting 1 to create a superficial skin wound. In group 2, it was injured with setting 5 to make a deeper wound, and in group 3, skin wound was performed with setting 10 making the deepest wound in the experiment. After the wounds were created on the rat skin, a full-thickness skin biopsy was taken from the middle of the cranial margin of the wound, including both the wound surface and the healthy skin in a specimen. Healing time of the wounds of animals was recorded in the experiment groups. Then, the results were compared statistically between the groups. In the histologic assessment, both the thickness of the remnant of the epidermis in the wound surface and the thickness of the healthy epidermis were measured under light microscope. Thickness of the epidermis remaining after wounding was statistically compared among the groups and with the healthy epidermis. The mean thickness of the remaining epidermis was determined for each group. It was higher in the superficial wounds than in the deep wounds, because of the removal of the skin from its outer surface through the deep layers of the skin with waterjet device. The most superficial wound in the experiment was observed in group 1, which was statistically different from the wounds of group 3, whereas there was no difference between the wounds of groups 1 and 2. Compared with the wounds of groups 1 and 2, the wounds in group 3 were significantly deeper than the wounds of other groups, which was statistically significant. In all groups, mean thickness of epidermis in the wound surface showed statistically significant difference from that in the healthy skin. When compared with the healing times of the wounds in the groups, a statistically significant difference was found between them. Creation of a split-skin wound, by using the waterjet system, provides a wound in reproducible size and depth, also in a standardized and rapid manner. Moreover, it makes precise and controlled wound creation in the rat skin.

Effect of oil-based calcium hydroxide (Osteoinductal) on distraction osteogenesis in rabbit mandible.

OBJECTIVE: The objective of this study was to evaluate the effects of oil-based calcium hydroxide on mandibular lengthening during distraction osteogenesis. STUDY DESIGN: Twenty-four New Zealand white rabbits underwent unilateral mandibular osteotomy. The rabbits were divided into 4 groups containing 6 each: groups 1 and 3 were control groups and groups 2 and 4 were test groups. Oil-based calcium hydroxide suspension was applied to test groups' corticotomy gap after osteotomy during operation. No treatment was applied to the control groups. After 5 days' latency period, distraction was commenced at a rate of 0.8 mm/day for 10 days via custom-made distractor. Groups 1 and 2 were killed 14 days after distraction and groups 3 and 4 were killed 28 days after distraction. RESULTS: Quantitative computerized tomography evaluation did not demonstrate a difference mean the density and the area of the regeneration between groups 1 and 3, but there was a significant difference groups 2 and 4. Histomorphometric evaluation demonstrated that there was a significant difference between test and control groups in new bone volume formation during distraction osteogenesis. CONCLUSION: Application of oil-based calcium hydroxide paste during the osteotomy phase of distraction osteogenesis increased regeneration and new bone volume formation.