Search

Aim The aim of this study was to examine the role of hereditary thrombophilia in the development of fetal growth retardation (FGR) in the population of Central Russia. Methods The case–control study sample included 497 women in the third trimester of pregnancy recruited during 2009–2013. The participants were enrolled into two groups: patients with FGR (n = 250) and controls without FGR (n = 247). The participants were genotyped for four genetic markers of hereditary thrombophilia: factor V Leiden (G > A FV, rs6025), prothrombin (G > A FII, rs1799963), factor VII (G > A FVII, rs6046), and fibrinogen (G > A FI, rs1800790). Results The genetic factors for an increased risk of FGR were allele G of rs6046 (odds ratio [OR] = 2.34) and genotype GG of rs6046 (OR = 2.64), whereas genotype GA of rs6046 had the protective value (OR = 0.42). A combination of alleles G of rs1799963, A of rs6046, and G of rs1800790 (OR = 0.31) reduces the risk of FGR. Conclusion Polymorphism rs6046 of the FVII gene is associated with the development of FGR.

This paper reviews the basic physical notions underlying microwave sintering and the theoretical and numerical models of the microwave sintering process. The propagation and absorption of electromagnetic waves in materials, and the distribution of electromagnetic field in cavity resonators that serve as applicators for microwave processing are discussed and the electromagnetic modeling of such applicators is reviewed. The microwave absorption properties of ceramic and metal powder materials and the methods of their description are addressed. Self-consistent electromagnetic and thermal models that are capable of predicting the temperature distribution in the microwave-heated materials and dynamic effects such as thermal runaway instabilities are reviewed. The multiphysics simulations that combine electromagnetic, thermal, and sintering models and result in predicting densification, shrinkage, and grain structure evolution are discussed in detail. The significance of microwave nonthermal effects in sintering is demonstrated based on the experimental results, and the models of such effects are reviewed.

The human endometrium is a dynamic tissue that undergoes cycles of growth and regression with each menstrual cycle. Adult progenitor stem cells are likely responsible for this remarkable regenerative capacity; these same progenitor stem cells may also have an enhanced capacity to generate endometriosis if shed in a retrograde fashion. The progenitor stem cells reside in the uterus; however, less-committed mesenchymal stem cells may also travel from other tissues such as bone marrow to repopulate the progenitor population. Mesenchymal stem cells are also involved in the pathogenesis of endometriosis and may be the principle source of endometriosis outside of the peritoneal cavity when they differentiate into endometriosis in ectopic locations. Finally, besides progenitor stem cells, recent publications have identified multipotent stem cells in the endometrium. These multipotent stem cells are a readily available source of cells that are useful in tissue engineering and regenerative medicine. Endometrial stem cells have been used to generate chondrocytes, myocytes, neurons, and adiposites in vitro as well as to replace dopaminergic neurons in a murine model of Parkinson's disease.

Abnormal uterine bleeding is the leading indication for discontinuation of long-term progestin-only contraceptives. Histological sections of endometria from long-term progestin-treated patients display abnormally enlarged blood vessels that are prone to bleed in a nonuniform manner. Because it has been complex to attain patients willing to complete long-term studies, and good quality endometrial tissues have proven difficult to obtain, animal models have been used to obviate this problem. In this review, we describe these models including the guinea pig, an animal model we have previously investigated, to assess the mechanisms involved in abnormal uterine bleeding following long-term progestin-only contraception.

Tissue factor (TF), is a cellular receptor that binds the ligand factor VII/VIIa to initiate the blood coagulation cascade. In addition to its role as the initiator of the hemostatic cascade, TF is known to be involved in angiogenesis via an interaction with factor VIIa and protease-activated receptor-2 (PAR-2). In this article we review previous studies from our laboratory demonstrating that the pattern and level of TF expression is altered in multiple cell types derived from eutopic and ectopic endometrium from women with endometriosis compared with normal endometrium. We posit that the inflammatory environment that occurs in ectopic and eutopic endometrium from patients with disease results in high TF expression that in turn, signals via PAR-2 to further produce inflammatory cytokine or chemokine production and macrophage recruitment. Thus, our studies suggest that TF might be an ideal target for therapeutic intervention in endometriosis.

Preeclampsia is associated with an increased release of factors from the placental syncytium into maternal blood, including the antiangiogenic factors soluble fms-like tyrosine kinase-1 and soluable endoglin, the antifibrinolytic factor plasminogen activator inhibitor-1, prostanoids, lipoperoxides, cytokines, and microparticles. These factors are suggested to promote maternal endothelium dysfunction and are associated with placental damage in pregnancies also complicated with intrauterine growth restriction (IUGR). In this report, we briefly describe the interaction of syncytial factors with hypoxia, reactive oxygen species, and apoptosis in the pathophysiology of preeclampsia and IUGR. Given the critical role of the syncytium in these complications of pregnancy, we also present a novel methodology in which laser capture microdissection followed by Western blotting is used to assess levels of syncytial Fas ligand, a key protein in the apoptotic cascade.

We showed that decidualized stromal cells of luteal phase and pregnant human endometrium express tissue factor (TF), the primary initiator of hemostasis, thereby suggesting a mechanism by which perivascular decidual cells can mitigate the risk of hemorrhage during endovascular trophoblast invasion. Progestins enhanced TF mRNA and protein levels in monolayers of human endometrial stromal cells (HESCs), with estradiol (E2) + progestin, further enhancing TF levels despite a lack of response to E2 alone. This differential ovarian steroid response has been found for several decidualization markers. Further studies with cultured HESCs established that elevated TF levels are mediated by the progesterone receptor and are maintained for weeks in response to E2 plus progestin, thus simulating the chronic upregulation of TF levels observed in decidualized HESCs in vivo. Recent studies revealed that elevated TF expression during in vitro decidualization of HESCs involved both the EGFR and progesterone receptor. Thus, enhancement of TF mRNA and protein levels in the HESCs required co-incubation with a progestin (MPA) and an EGFR agonist such as EGF or TGF-alpha. In correspondence with co-elevation of EGFR and TF in decidualized HESCs in sections of luteal phase and pregnant endometrium, EGFR levels proved to be progestin-enhanced in the cultured HESCs. We established that progestin-enhanced TF expression in HESCs was trancriptionally regulated, then evaluated the relative roles of SP and EGR-1 sites on the TF promoter in regulating this expression. Transient transfections with a series of promoter constructs containing overlapping SP and EGR-1 sites and with constructs in which the EGR-1 and SP sites were systematically inactivated by site-directed mutagenesis established the dominance of SP sites in both basal and progestin-enhanced TF transcriptional activity. Additional experiments involving transient transfections with SPloverexpressing vectors and with a specific blocker of if Sp1 binding to its corresponding GC box specified the importance of the Sp1 transcription factor. These results were further validated by immunostaining, which revealed that the ratio of Sp1 to Sp3 increased during progestin-regulated decidualization of HESCs in vitro and in vivo. The absence of canonical estrogen and progesterone response elements from either the TF or Sp1 gene promoters suggests that the EGFR may help to mediate progestin-enhanced TF expression during decidualization of HESCs.

Introduction: Preeclampsia and IUGR have been linked to improper trophoblast migration that impairs maternal spiral artery transformation minimizing vessel dilation and therefore restricting blood flow to the developing fetus. Endothelial cells are thought to play an essential role in directing trophoblast migration and transformation, although the mechanism by which this occurs is not fully understood. We have developed a novel in vitro system that evaluates endothelial-trophoblast interaction and signaling in a three-dimensional environment. Methods: An immortalized human endometrial endothelial cell line (HEEC) (Krikun et al., 2004) and first trimester trophoblast cell lines HTR-8 and Swan.71 were used. Endothelial transformation into vessel-like structures occurred in Matrigel Basement Membrane Matrix. Cell membrane linker dye and OpenLab Image Analysis software were used to monitor trophoblast migration and transformation. Cytokine and chemokine production was determined using a multiplex bead assay. Results: Upon differentiation in matrigel, endothelial cells undergo a shift in cytokine production characterized by an increased secretion of chemokines. First trimester trophoblast cells migrate toward the differentiated endothelium, and reach it within 4–8 hr. Complete replacement of the endothelium is seen by 48 hr. The transformed tubes maintain structure and remain functional for several weeks allowing for further co-culture studies. Conclusion: We report the characterization of a novel three-dimensional in vitro system of trophoblast–endothelium cell interaction. We found significant changes in the phenotype (cytokine expression and LPS responses) of endothelial cells upon differentiation in matrigel as compared to the monolayer culture. These changes may be necessary for the endothelium to direct trophoblast migration. Furthermore, this model represents an ideal co-culture system to evaluate the role of additional cell types, e.g. immune cells, involved in the process of spiral artery transformation.

SUMMARY The effects of rootstock, irrigation regime and water salinity on the vertical distribution of vesicular-arbuscular mycorrhiza (VAM) of citrus roots were investigated in the field. Rootstocks differed in the uniformity of the vertical distribution of VAM, notably, Rough lemon exhibited a uniform vertical distribution and Sour orange a non-uniform distribution with decreased VAM infection at depth. Decreasing the interval between irrigations reduced VAM infection of Sour orange, especially in the upper layers of soil. Increased salinity of irrigation-water reduced VAM in deep layers of soil.

SUMMARY Pepper (Capsicum annuum) seeds were sown in nutrient-poor sand or nutrient-rich peat/vermiculite amended or not amended with Glomus macrocarpum. The vesicular-arbuscular mycorrhizal (VAM) seedlings were irrigated with three levels of nutrient solution, and transplanted into four levels of P-amended soil, each of which was irrigated with two levels of nutrient solution minus P. Mycorrhizal seedlings in sand were responsive to increasing nutrient levels; in nutrient-rich peat the seedlings did not respond to additional fertilisation. The greatest seedling development accompanied by good fungus colonisation was in nutrient-poor medium irrigated with the highest nutrient solution tested (18 mM N, 1.2 mM P, and 7 mM K). Non-VAM plants almost ceased growing between the weeks 4 and 5, whereas VAM plants increased in weight by 41–188%. After transplanting, sand-grown seedlings benefited from VAM when 300 mg P/kg or more was added to the soil but peat-grown plants did not. Fruit development was delayed in all non-VAM plants compared with VAM ones.

Summary Isolates of Glomus macroncarpum Tul. & Tul. grown in soil cultures from single spores were tested at known numbers of propagules ml−1 soil for their efficacy in promoting growth of bell pepper (Capsicum annuum L.) seedlings. The soil cultures, propagated under similar growth conditions, had from 0.02 to 25 propagules ml−1 as measured by the most probable number technique. Seven cultures with similar levels of inoculum density (a median of 7 propagules ml−1) were used undiluted, and at 10−1 and at 10−2 dilutions to test efficacy of the isolates. Also, cultures with originally dissimilar propagule levels (0.02 to 15 ml−1) were diluted to uniform inoculum density levels and tested for efficacy. Large intra-species variation in efficacy occurred in isolates collected from different soils and in those isolated from the same soil. Differences in the growth enhancement ability of isolates were evident from four weeks after seeding until harvest. The best isolates were superior at all inoculum levels tested but the ranking of isolates differed with the inoculum density. A significant positive correlation was found between initial G. macrocarpum propagules ml−1 soil and all plant height and weight parameters measured. Growth of mycorrhizal plants was significantly greater than that of non-mycorrhizal plants when more than 0.5 propagule ml−1 was present. With more than 5 ml−1, 70% of the isolates were effective. A minimum level of 1 propagule ml−1 is suggested for infestation of pepper seed beds; greater benefits can be expected from higher levels up to at least 10 to 15 propagules ml−1.

SUMMARY Recovery from water stress was studied on similarly sized VA mycorrhizal and non-mycorrhizal rough lemon seedlings (Citrus jambhiri Lush). VA mycorrhiza affected stomatal conductance, photosynthesis and proline accumulation, but not leaf water potential, suggesting that most of the effect of the mycorrhizal association is on stomatal regulation rather than on root resistance.