Search results for "Yolk sac"

Antiphosphatidylserine Antibodies Affect Rat Yolk Sacs in Culture: a Mechanism for Fetal Loss in Antiphospholipid Syndrome

2004

PROBLEM: A variety of reproductive impairments have been reported in the context of the antiphospholipid syndrome (APS). APS is associated with the presence of antibodies to negatively charged phospholipids that may affect the outcome of pregnancy. METHOD OF STUDY: Rat embryos were cultured within their yolk sacs. The effects of two antiphosphatidylserine monoclonal aPS antibodies (HL5B, RR7F) regarding their influence on growth and apoptotic events of the yolk sacs, as well as on growth and the morphology of the embryos, were studied. RESULTS: Exposure of rat embryos and their yolk sacs to aPS inhibited yolk sac growth. Moreover, increased number of apoptotic events of giant cells in the a…

Acute hepatotoxicity induced by quetiapine fumarate in larval zebrafish

2016

The serosa of Manduca sexta (Insecta, Lepidoptera): ontogeny, secretory activity, structural changes, and functional considerations

2001

In Manduca sexta, the blastoderm forms successively and becomes immediately cellularized as the cleavage energids reach the surface of the oocyte. Presumptive serosal cells are large and contain 2 or 4 large polyploid nuclei; presumptive embryonic cells are small and mononuclear. All parts of the blastoderm participate in the uptake and digestion of yolk material. About 10 h post-oviposition, the blastoderm breaks at the amnioserosal fold and the extraembryonic part closes above the germ band and constitutes the serosa (12 h post-oviposition, i.e. 10% development completed). At once, the serosa starts to secrete a cuticle consisting of an epi- and a lamellated endocuticle. Detachment of the…

Posters
Early pregnancy
P01First trimester normograms for a wide variety of ultrasound, hemodynamic and serum parameters

2000

Background The aim of the study was to assess prospectively the evolution of multiple clinical parameters throughout the first trimester of pregnancy. Method A transvaginal ultrasound examination and a blood test was weekly performed until the 13th gestational week in a group of healthy volunteers. A total of 25 spontaneously conceived singleton pregnant women with good pregnancy outcome finally completed the study. The evolution of 10 transvaginal ultrasound parameters, 5 Doppler measurements and 6 serum parameters was studied. Results An increasing trend with advancing gestation was evident for the mean gestational sac (MSD) and amniotic sac (AS) diameters, trophoblastic rim, CRL and seru…

Specific, concentration-dependent uptake of vitellin by the oocytes ofNereis virens (Annelida, Polychaeta) in vitro

1991

One purpose of this study was the development of methods for radioactive labeling and handling of the yolk protein of Nereis virens, another, the utilization of this tracer in nereid oocyte cultures to describe the kinetics and specificity of yolk protein uptake. Accumulation of labeled yolk protein by growing oocytes is linear over time, specific for yolk protein, and dependent on tracer concentration in the medium. Incorporation of yolk protein follows saturation kinetics which allows us to reproducibly determine the characteristics of this process. The apparent KM of ∼ 1 × 10−8 M indicates the high affinity of the transport system; the Vmax (160–400 pg protein/day × oocyte) reveals that …

Trisomy 12 and translocation (7;9) in an ovarian immature teratoma.

1989

We report a case of an immature malignant ovarian teratoma with peritoneal implants diagnosed in an 18-year-old woman. The tumor was brought into remission after surgery (three laparotomies) and adjuvant chemotherapy. A residual peritoneal implant showed a mature epithelial and glial configuration. Histologically, the neuroectodermal component was dominant in the original tumor as well as in the metastases, being confirmed by immunohistochemistry and electron microscopy. A stem cell line has been obtained with cell culture, having a germ cell character and a yolk sac configuration. This line possessed a trisomy 12 and a translocation (7;9) similar to other chromosomal abnormalities describe…

YOLK SAC DEL TESTICOLO: Raro Caso con Metastasi Gigante Retroperitoneale

1989

The authors restorate a case of primary testis tumor (Yolk Sac Tumor) and giant retroperitoneal metastasis clinically evident as a voluminous abdominal mass (23 cm) and associated virilizing syndrome. the diagnostic and therapeutic procedure performed is described.

In Vivo Cardiotoxicity Induced by Sodium Aescinate in Zebrafish Larvae

2016

Sodium aescinate (SA) is a widely-applied triterpene saponin product derived from horse chestnut seeds, possessing vasoactive and organ-protective activities with oral or injection administration in the clinic. To date, no toxicity or adverse events in SA have been reported, by using routine models (in vivo or in vitro), which are insufficient to predict all aspects of its pharmacological and toxicological actions. In this study, taking advantage of transparent zebrafish larvae (Danio rerio), we evaluated cardiovascular toxicity of SA at doses of 1/10 MNLC, 1/3 MNLC, MNLC and LC10 by yolk sac microinjection. The qualitative and quantitative cardiotoxicity in zebrafish was assessed at 48 h p…

Multiple Receptors Mediate apoJ-Dependent Clearance of Cellular Debris into Nonprofessional Phagocytes

2001

Phagocytosis of apoptotic, senescent, and dying cells by macrophages is a well characterized process. More recently it has been shown that in addition to macrophages vital neighboring cells in the affected tissue participate in the cellular clearance. While scavenger receptors have been shown to mediate uptake into macrophages, it is poorly understood how cellular debris is internalized by nonprofessional phagocytes. We here analyze the endocytic activity of vital fibroblasts and epithelial cells exposed to cellular debris and membrane remnants. We show a mutual stimulation in the endocytosis of debris and apolipoproteinJ (clusterin) in these cells. Experiments using RAP (receptor-associate…

Cabut, a C2H2 zinc finger transcription factor, is required during Drosophila dorsal closure downstream of JNK signaling.

2005

AbstractDuring dorsal closure, the lateral epithelia on each side of the embryo migrate dorsally over the amnioserosa and fuse at the dorsal midline. Detailed genetic studies have revealed that many molecules are involved in this epithelial sheet movement, either with a signaling function or as structural or motor components of the process. Here, we report the characterization of cabut (cbt), a new Drosophila gene involved in dorsal closure. cbt is expressed in the yolk sac nuclei and in the lateral epidermis. The Cbt protein contains three C2H2-type zinc fingers and a serine-rich domain, suggesting that it functions as a transcription factor. cbt mutants die as embryos with dorsal closure …