bromochloroacetic-acid and Fetal-Death

Nitric oxide (NO) has been implicated as a signalling molecule in many cellular processes. As nitric oxide synthase 2 (NOS-2) is the main isoform expressed in mouse decidua and metrial gland, mice with a targeted disruption of the gene encoding NOS-2 were used to determine the potential roles of this enzyme during pregnancy. Reproductive success and the morphology of implantation sites throughout pregnancy were compared in NOS-2 deficient (NOS-2-/-) and wild-type (WT) mice. Although there were no significant differences in the duration of gestation or birth weight, NOS-2-/- mice had significantly fewer viable embryos at mid-gestation and delivered smaller litters than did WT mice. Histological sections of uteroplacental units from WT and NOS-2-/- mice were compared to establish the mechanisms underlying the loss of fetuses. No morphological differences were observed on day 6 or day 8 of gestation, indicating that implantation and early development of implantation sites were unaffected by the absence of NOS-2. However, by mid-gestation, decidua of NOS-2-/- mice had reduced cellularity and their decidual arteries had abnormally thickened walls. These observations were quantified by morphometric measurements, which showed a significant reduction in decidual cellular area and a significant increase in the blood vessel wall:lumen ratio in NOS-2-/- mice. The increase in the thickness of the blood vessel walls was not due to abnormal cellular infiltration or to altered expression of alpha-actin in vascular smooth muscle. These results indicate that NOS-2 has a functional role in the maintenance of decidual cellular integrity and development of appropriate uterine vasculature, and may play a supportive role in promoting embryo survival.

Topics: Actins; Animals; Arteries; Decidua; Enzyme-Linked Immunosorbent Assay; Female; Fetal Death; Gestational Age; Histocytochemistry; Immunoblotting; Immunohistochemistry; Interferon-gamma; Keratins; Litter Size; Mice; Mice, Knockout; NADPH Dehydrogenase; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Pregnancy; Pregnancy, Animal; RNA, Messenger

We analysed the early implantation tissues of normal women and of a patient with congenital factor XIII deficiency in order to study the role of maternal subunit A of factor XIII (XIIIA) in the development of extravillous cytotrophoblast. The patient had received adequate administration of factor XIIIA concentrate only up to 7 weeks of gestation (wG). Her pregnancy was maintained until the latter half of 8 wG, but was terminated by intrauterine fetal death at 9 wG. Immunohistochemical staining of cytokeratin, XIIIA and subunit S of factor XIII was performed in the early implantation tissues of normal women and of this patient. Numerous well-formed cytotrophoblastic shells and Nitabuch's layers were detected in implantation tissues at 7-8 wG in normal women, and XIIIA was present in the intercellular space in well-formed cytotrophoblastic shells, while the cytotrophoblastic shells and Nitabuch's layers in this patient's implantation tissue were poorly-formed. Furthermore, XIIIA was not detected around them. It is suggested that when the maternal plasma activity of factor XIII is low, the concentration of XIIIA at the placental bed is also low, leading to the insufficient formation of cytotrophoblastic shell and therefore an increased probability of miscarriage in patients with congenital factor XIII deficiency.

Topics: Adult; Factor XIII Deficiency; Female; Fetal Death; Fluorescent Antibody Technique, Indirect; Humans; Keratins; Pregnancy; Pregnancy Complications, Hematologic; Pregnancy Trimester, First; Transglutaminases; Trophoblasts

It has been reported previously that keratin 8 (K8)-deficient mice of one strain die from a liver defect at around E12.5, while those of another strain suffer from colorectal hyperplasia. These findings have generated considerable confusion about the function of K8, K18 and K19 that are co-expressed in the mouse blastocyst and internal epithelia. To resolve this issue, we produced mice doubly deficient for K18 and K19 leading to complete loss of keratin filaments in early mouse development. These embryos died at around day E9.5 with 100% penetrance. The absence of keratins caused cytolysis restricted to trophoblast giant cells, followed by haematomas in the trophoblast layer. Up to that stage, embryonic development proceeded unaffected in the absence of keratin filaments. K18/19-deficient mouse embryos die earlier than any other intermediate filament knockouts reported so far, suggesting that keratins, in analogy to their well established role in epidermis, are essential for the integrity of a specialized embryonic epithelium. Our data also offer a rationale to explore the involvement of keratin mutations in early abortions during human pregnancies.

Topics: Animals; Blotting, Western; Cytoskeleton; Embryo, Mammalian; Epithelial Cells; Female; Fetal Death; Fluorescent Antibody Technique; Gene Deletion; Genotype; Giant Cells; Intestinal Mucosa; Intestines; Keratins; Mice; Mice, Inbred C57BL; Mice, Knockout; Mutagenesis, Site-Directed; Necrosis; Phenotype; Polymerase Chain Reaction; Pregnancy; Pregnancy Complications; Trophoblasts; Uterine Hemorrhage

To investigate the expression and biological roles of cytokeratin 19 (K19) in development and in adult tissues, we inactivated the mouse K19 gene (Krt1-19) by inserting a bacterial beta-galactosidase gene (lacZ) by homologous recombination in embryonic stem cells, and established germ line mutant mice. Both heterozygous and homozygous mutant mice were viable, fertile, and appeared normal. By 7.5-8.0 days post coitum (dpc), heterozygous mutant embryos expressed lacZ in the notochordal plate and hindgut diverticulum, reflecting the fact that the notochord and the gut endoderm are derived from the axial mesoderm-originated cells. In the adult mutant, lacZ was expressed mainly in epithelial tissues. To investigate the possible functional cooperation and synergy between K19 and K8, we then constructed compound homozygous mutants, whose embryos died approximately 10 dpc. The lethality resulted from defects in the placenta where both K19 and K8 are normally expressed. As early as 9. 5 dpc, the compound mutant placenta had an excessive number of giant trophoblasts, but lacked proper labyrinthine trophoblast or spongiotrophoblast development, which apparently caused flooding of the maternal blood into the embryonic placenta. These results indicate that K19 and K8 cooperate in ensuring the normal development of placental tissues.

Topics: Animals; Crosses, Genetic; Embryo, Mammalian; Female; Fetal Death; Fetal Growth Retardation; Fluorescent Antibody Technique; Galactosidases; Gene Deletion; Gene Targeting; Genes, Reporter; Genotype; Germ-Line Mutation; In Situ Hybridization; Keratins; Male; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Mice, Knockout; Phenotype; Placenta; Placental Circulation; Pregnancy; Recombination, Genetic; RNA, Messenger; Stem Cells; Trophoblasts

In contrast to tubal abortions, viable ectopic pregnancies in color Doppler ultrasonography exhibit a signal-intensive ring around the gestational sac. We investigated the underlying differences in implantation and placentation.. Histologic sections of fallopian tubes carrying viable tubal pregnancies (13 patients) and tubal pregnancies that aborted (8 patients) were immunostained for cytokeratin, MIB-1, CD-34, and CD-68. The data were studied by computer-aided image analysis followed by statistical evaluation (Student t test, P <.05).. In contrast to tubal abortions, viable tubal pregnancies are characterized by implantation at the mesosalpingial rather than at the antimesosalpingial side of the organ. They exhibit deeper trophoblast invasion into the thickened tubal wall, more intense trophoblast proliferation (P <.001), and increased villous vascularization (P <.001).. The morphologic findings correlate with preoperative Doppler ultrasonography. They suggest that trophoblast invasion, placental growth, and the fate of tubal pregnancies depend on the implantation site. They encourage a conservative management of anti-mesosalpingially implanted, nonviable ectopic pregnancies in clinically stable patients.

Topics: Antigens, CD; Antigens, CD34; Antigens, Differentiation, Myelomonocytic; Antigens, Nuclear; Embryo Implantation; Fallopian Tubes; Female; Fetal Death; Humans; Immunohistochemistry; Keratins; Ki-67 Antigen; Nuclear Proteins; Placentation; Pregnancy; Pregnancy, Tubal; Trophoblasts; Ultrasonography

An immunohistochemical study of renal tubule cell differentiation in hydrops fetalis was performed using antibodies against lysozyme, CD15, keratin, epithelial membrane antigen and Leu-7, and formalin-fixed, paraffin-embedded sections of tissue that was obtained at autopsy. In 3 cases among 17 cases of hydrops fetalis (17.6%) there was a marked decrease in the number of cells stained positively for lysozyme, suggesting abnormal differentiation of the cells of the proximal convoluted tubules. This is the first report concerning the abnormalities of the renal tubular epithelium in hydrops fetalis.

Topics: CD57 Antigens; Cell Differentiation; Epithelium; Female; Fetal Death; Gestational Age; Humans; Hydrops Fetalis; Immunohistochemistry; Keratins; Kidney Tubules; Lewis X Antigen; Male; Mucin-1; Muramidase

The X-linked mouse mutant phenotype, tattered (Td), is associated with prenatal lethality of males and has been mapped previously to the proximal region of the mouse X chromosome. We report here a refined position for Td and demonstrate that it lies in the approximately 0.9-cM interval between DXMit55 and Xkh. This enables us to predict that the human homologue lies either between CLCN5 and the evolutionary breakpoint that lies between GATA1 and PFC or distal to XK and proximal to the evolutionary breakpoint that lies between XK and DMD. Histological analysis of dorsal skin taken from 5-day-old heterozygous animals revealed that the mutation was associated with patches of hyperkeratinzation in the epidermis and in the hair follicles, accompanied by a mild inflammatory infiltrate in the underlying dermis.

Topics: Animals; Chromosome Mapping; Embryonic and Fetal Development; Female; Fetal Death; Genetic Linkage; Genetic Markers; Humans; Keratins; Male; Mice; Mutation; X Chromosome

The identification of ductal plate cells as likely progenitors for bile duct epithelium and hepatocytes and their possible reappearance as oval cells in the regenerating liver have generated much interest in their pluripotential capacities. We have examined the distribution of three hematopoietic stem cell markers, c-kit, CD34, and CD33 in addition to laminin, the standard cytokeratin markers CAM 5.2, CK 18, and CK 7 and the oval cell marker OV-6 in fetal liver during various stages of development. Hematopoietic stem cell markers were expressed in ductal plate cells in a pattern similar to the early cytokeratin markers CAM 5.2 and CK 18. Cells stained strongly for these early cytokeratin markers until 22 weeks. Thereafter, the expression of these markers decreased while positivity for CK 7 increased. Bile duct cells showed a distribution of hematopoietic and cytokeratin markers resembling that of ductal plate cells. Both ductal plate cells and bile duct cells expressed OV-6 strongly throughout development. This study showed similarity between hepatic and bile duct precursors and bone marrow stem cells. The comparable distribution of markers in bile duct epithelium and ductal plate cells may imply fewer transitional stages between ductal plate cells and bile duct epithelium than between the putative stem cells and hepatocytes.

Topics: Antigens, CD; Antigens, Differentiation, Myelomonocytic; Antigens, Surface; Autopsy; Bile Ducts; Biomarkers; Embryo, Mammalian; Embryonic and Fetal Development; Fetal Death; Fetus; Gestational Age; Hematopoietic Stem Cells; Humans; Immunoenzyme Techniques; Infant, Newborn; Infant, Premature; Keratins; Laminin; Liver; Sialic Acid Binding Ig-like Lectin 3

Using immunohistochemical (IH) staining for epithelial membrane antigen (EMA), keratin, Leu-7, Ca 19-9, secretory component (SC) and surfactant protein A (SPA) on formalin-fixed, paraffin-embedded autopsy cases of stillbirth and early neonatal death, the normal profile of IH-positive cells in the airway of the developing fetal lung was clarified. IH-positive cells first appeared in the proximal region of the lung, and then in the distal region. Keratin-positive cells and EMA-positive cells were abundant at the 10th gestational week (10 GW), the earliest stage observed in this study. Cells positive for Leu-7 and Ca 19-9 appeared during the time when bronchial branches developed, and were abundant at around 16 GW, the time of completion of bronchial branching. On the other hand, SPA- and SC-positive cells appeared after the completion of bronchial branching, and were abundant around 29 GW and 34 GW, respectively. Acinous structural development was observed in terms of radial alveolar count (RAC). Cases of lung hypoplasia defined as a lung weight to body weight ratio of under 0.012 at > or = 28 GW or under 0.015 at < 28 GW showed a rather high tendency of abnormalities of cellular differentiation revealed by IH staining.

Topics: Bronchi; CD57 Antigens; Cell Differentiation; Epithelium; Female; Fetal Death; Fetal Diseases; Humans; Immunohistochemistry; Infant, Newborn; Keratins; Lung; Male; Membrane Glycoproteins; Organ Size; Pregnancy; Pulmonary Alveoli

Keratin 8 (mK8) and its partner keratin 18 (mK18) are the first intermediate filament proteins expressed during mouse embryogenesis. They are found in most extraembryonic and embryonic simple epithelia, including trophectoderm, visceral yolk sac, gastrointestinal tract, lungs, mammary glands, and uterus. We report that a targeted null mutation in the mK8 gene causes mid-gestational lethality. Mutant embryos are growth retarded and suffer from internal bleeding, with an abnormal accumulation of erythrocytes in fetal livers. The mK8- phenotype has 94% penetrance, with a few mice surviving into adulthood. We suggest that mK8/mK18 filaments are important for the integrity of the fetal liver, like specialized human epidermal keratins for the integrity of the epidermis. This phenotype in mice differs from the reported function of simple epithelium keratins in Xenopus at the gastrulation stage. In mice, mK8 fulfills a vital function at 12 days postcoitum.

Topics: Animals; Epithelium; Erythrocyte Aggregation; Fetal Death; Gene Deletion; Genes, Lethal; Hemorrhage; Intermediate Filaments; Keratins; Liver; Mice; Mice, Inbred C57BL; Mutagenesis, Site-Directed

Evidence is reviewed in support of the hypothesis that immature unkeratinized fetal skin must be present if bovine fetal mummification is to occur. The reduction in fetal and amniotic fluid is considered to be the result of intrafetal (fetal death) or prefetal (caruncular damage) effects on the normal net fluid flow from the maternal circulation through the fetal circulation and then across the fetal skin into the amniotic cavity. As the skin is keratinized permeability is reduced drastically thus limiting fluid loss from the fetus.

Topics: Amniotic Fluid; Animals; Autolysis; Cattle; Female; Fetal Death; Keratins; Maternal-Fetal Exchange; Ossification, Heterotopic; Permeability; Postmortem Changes; Pregnancy; Skin; Skin Physiological Phenomena