Significance of pregnancy test false negative results due to elevated levels of ß-core fragment hCG.

Very high levels of ß-core fragment human chorionic gonadotrophin (ßcf-hCG) are reported to potentially cause false negative results in point-of-care (POC)/over-the-counter (OTC) pregnancy tests. To investigate this further, women's daily early morning urine samples, collected prior to conception and during pregnancy, were analysed for intact, free ß-, and ßcf-hCG. The proportion of ßcf-hCG was found to be related to that of hCG produced and in circulation. Therefore, best practice for accuracy testing of POC/OTC pregnancy tests would be to test devices against clinical samples containing high levels of ßcf-hCG as well as standards spiked with biologically relevant ratios.

Interfacial structure of immobilized antibodies and perdeuterated HSA in model pregnancy tests measured with neutron reflectivity.

Experimental studies of antibody adsorption and antigen binding that mimicked pregnancy test immunoassays have been performed using neutron reflectivity studies of a model antibody/antigen system immobilized on the silica/water interface. The study revealed the nature of the antibody/antigen interaction and also the importance of a blocking protein, in this case human serum albumin (HSA), that enhances the immunoassay's specificity and efficiency. Of central importance to this study has been the use of a perdeuterated human serum albumin (d-HSA), providing contrast that highlights the orientation and position of the blocking agent within the adsorbed layer. It was found that the adsorbed HSA filled the gaps between the preadsorbed antibodies on the substrate, with decreased adsorption occurring as a function of increased antibody surface coverage. In addition, the antigen binding capacity of the adsorbed antibodies was investigated as a function of antibody surface coverage. The amount of specifically bound antigen was found to saturate at approximately 0.17 mg/m(2) and became independent of the antibody surface coverage. The ratio of bound antigen to immobilized antibody decreased with increased antibody surface coverage. These results are of importance for a full understanding of immunoassay systems that are widely used in clinical tests and in the detection of environmental contaminants.

The Extracellular Vesicles Proteome of Endometrial Cells Simulating the Receptive Menstrual Phase Differs from That of Endometrial Cells Simulating the Non-Receptive Menstrual Phase.

Successful embryo implantation into a receptive endometrium requires mutual endometrial-embryo communication. Recently, the function of extracellular vehicles (EVs) in cell-to-cell interaction in embryo-maternal interactions has been investigated. We explored isolated endometrial-derived EVs, using RL95-2 cells as a model of a receptive endometrium, influenced by the menstrual cycle hormones estrogen (E2; proliferative phase), progesterone (P4; secretory phase), and estrogen plus progesterone (E2P4; the receptive phase). EV sized particles were isolated by differential centrifugation and size exclusion chromatography. Nanoparticle tracking analysis was used to examine the different concentrations and sizes of particles and EV proteomic analysis was performed using shotgun label-free mass spectrometry. Our results showed that although endometrial derived EVs were secreted in numbers independent of hormonal stimulation, EV sizes were statistically modified by it. Proteomics analysis showed that hormone treatment changes affect the endometrial EV's proteome, with proteins enhanced within the EV E2P4 group shown to be involved in different processes, such as embryo implantation, endometrial receptivity, and embryo development, supporting the concept of a communication system between the embryo and the maternal endometrium via EVs.

The role of extracellular vesicles in endometrial receptivity and their potential in reproductive therapeutics and diagnosis.

Extracellular vesicles (EVs) are small, nanometre sized, membrane-enclosed structures released by cells and are thought to be crucial in cellular communication. The cargo of these vesicles includes lipids, proteins, RNAs and DNA, and control various biological processes in their target tissues depending on the parental and receiver cell's origin and phenotype. Recently data has accumulated in the role of EVs in embryo implantation and pregnancy, with EVs identified in the uterine cavity of women, sheep, cows, horses, and mice, in which they aid blastocyst and endometrial preparation for implantation. Herein is a critical review to decipher the role of extracellular vesicles in endometrial receptivity and their potential in reproductive therapies and diagnosis. The current knowledge of the function of embryo and endometrial derived EVs and their cargoes, with regards to their effect on implantation and receptivity are summarized and evaluated. The findings of the below review highlight that the combined knowledge on EVs deriving from the endometrium and embryo have the potential to be translated to various clinical applications including treatment, a diagnostic biomarker for diseases and a drug delivery tool to ultimately improve pregnancy rates.

Metastatic choriocarcinoma in a middle-aged man presenting as a right thigh mass with venous thrombosis: a case report.

Choriocarcinoma is a highly aggressive beta-subunit of human chorionic gonadotropin (betaHCG)-producing germ cell tumor. In men, it is a rare neoplasm and can arise in the testes or in various extragonadal locations such as the retroperitoneum, mediastinum, and pineal body. We present a highly unusual case of a middle-aged man with primary metastatic betaHCG-producing choriocarcinoma of the right thigh along with right lower-extremity venous thrombosis. We comment on prognostic variables as well as discuss several theories to account for the unusual location of his choriocarcinoma.

Rituximab for the treatment of refractory idiopathic thrombocytopenic purpura (ITP) and thrombotic thrombocytopenic purpura (TTP): report of three cases.

Three patients (one with idiopathic thrombocytopenic purpura [ITP] and two with thrombotic thrombocytopenic purpura [TTP]) were treated with rituximab (anti-CD20 chimeric antibody) at a dose of 325 mg/m2 administered weekly after they failed standard therapies. The patient with ITP who did not respond to steroids and anti-D antibody administration achieved augmentation of her platelet counts up to 180 x 10(3)/microL after four doses of rituximab. Six months later, when her counts started to decrease, she received maintenance therapy with an additional course of 4 standard doses of antibody that resulted in consolidation of her platelet counts around 100 x 10(3)/microL. One patient with TTP and concurrent idiopathic nephropathy who was previously treated with plasmapheresis, steroids, and vincristine improved only after 4 weekly administrations of the antibody. Moreover, his nephrotic-range proteinuria resolved after he received rituximab. The other patient with chronic TTP who still relapsed after splenectomy received 5 doses of rituximab with concomitant plasmapheresis. His thrombocytopenia improved slowly, and his platelet count stabilized at 300 x 10(3)/microL. All three patients showed evidence of response to anti-CD20 antibody with improvement in clinical outcome as well as augmentation of platelet counts to normal levels. We conclude that rituximab is a useful immunomodulating adjunct in the treatment of refractory ITP and TTP.