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Ovarian hyperstimulation syndrome (OHSS) is a severe complication arising from controlled ovarian stimulation treatment. This iatrogenic condition is potentially lethal and occurs in 0.3-5% of stimulated ovarian cycles. hCG exacerbates OHSS. The pathophysiology of OHSS is still unknown; therefore, treatment regimens are aimed at ameliorating symptoms. Prominent features of OHSS are an elevated risk of thromboembolism due to enhanced production of von Willebrand factor by endothelial cells and ascites, or pulmonary edema due to increased vascular permeability followed by third space fluid accumulation. Both of these sequelae can be evoked by vascular endothelial growth factor (VEGF), also known as vascular permeability factor (VPF). High concentrations of VEGF/VPF have been demonstrated in ascitic fluid from patients with OHSS, but the source of VEGF/VPF in these patients remained unidentified. Here we report that the messenger ribonucleic acid expression of VEGF/VPF in human luteinized granulosa cells (GCs) is dose and time dependently enhanced by hCG in vitro. Furthermore, VEGF/VPF proteins are produced by GCs. Our results suggest that the effects of hCG on the development and course of OHSS may be mediated by the production of VEGF/VPF by GCs.

Vascularization is a prerequisit for corpus luteum formation. Angiogenesis is supposed to be regulated by vascular growth factors. Vascular endothelial growth factor (VEGF) induces specifically endothelial cell proliferation as well as angiogenesis and increases capillary permeability. With this study we demonstrate for the first time the presence of VEGF-mRNA in human luteinized granulosa cells by Northern blot technique. Granulosa cells were obtained from 11 individual patients undergoing ovarian stimulation for in vitro fertilization procedure. Two transcripts of VEGF-mRNA at 3.9Kb and at 4.3Kb could be detected in each case. Specific transcripts were expressed in different amounts. These results indicate that VEGF may promote at least in part vascularization of the human corpus luteum.

Polylactide (PLA) microcellular foams with well-defined cell morphology were successfully fabricated from poly­(l-lactide) (PLLA) and poly­(d-lactide) (PDLA) blends through a supercritical carbon dioxide (CO2) foaming method. The gaps between the melting temperature of homocrystallites (T m(HC)) and stereocomplex crystallites (T m(SC)) were utilized to improve PLA’s melt foaming behaviors (i.e., cell nucleation and cell morphology) owing to the existence of exclusive SC crystallites when the foaming temperature fell in between T m(HC) and T m(SC). Thanks to the enhanced melt strength, which resulted from the introduction of SC crystallites, the cell morphology transformed from elliptical to nearly circular and the cell collapse and coalescence reduced when foamed at high temperatures and pressures. The wider foaming processing window is favorable for actual industrial manufacture such as the continuous extrusion foaming process. In addition, PLA foams possessing more SC crystallites exhibit higher heat resistance, which further broadens their applications in high-temperature conditions.

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Lightweight shape memory thermoplastic polyurethane (TPU)/polylactide (PLA) foams with favorable mechanical properties and anti-shrinkage properties were prepared by a facile and green supercritical carbon dioxide foaming technology in this work. The introduction of cells enhanced the shape recovery ratio of TPU/PLA blends from 72.7 to 91.7% due to the good resilience and deformability of cells. Meanwhile, the existence of PLA and crystals in TPU/PLA foams improved the shape fixing ratio of TPU/PLA foams to 92.7% by restricting the movement of TPU molecular chains. The shape memory properties of TPU/PLA foams can be tuned by the control of the cell structure and expansion ratio. Additionally, the addition of PLA restrained the shrinkage of TPU/PLA foams, and the expansion ratio of TPU/PLA foams increased to 7.1. The mechanical properties of TPU/PLA foams were enhanced by the addition of PLA.

Crystallization behavior of polylactic acid (PLA) under CO 2 is meaningful due to its effect on foaming behavior during CO 2 foaming, while present studies mainly concentrated on overall crystallization behavior. In this study, the effect of CO 2 on nucleation and spherulite growth of PLA crystals was in situ investigated separately. During saturation, sorption of CO 2 in PLA diluted the molecular chain density, thus increasing molecular chain mobility and weakening the interchain interaction, which reduced the amount of crystal nuclei in PLA. On the other hand, the spherulite growth rate reduced at high temperature and increased at low temperature attributed to the enhanced chain mobility under CO 2 . Thus, overall crystallization was controlled by the spherulite growth rate at low temperature and crystalline nucleation at high temperature under CO 2 . Besides, CO 2 restricted lamella branching, resulting in an increased lamella thickness and z axis size. Current results revealed the effect of tunable molecular chain mobility and the interchain interaction adjusted by CO 2 on nucleation and spherulite growth of PLA.

Human RCC inhibits the host antitumor immune response by promoting PGE(2) production and Th2 cytokines in PBMC. Selective inhibition of COX-2 may have a role in abrogating this effect.