Search results for " ovary"

When Periods Stop: Long-Term Consequences of PCOS

2009

Let's rescue oocytes: in vitro maturation 2.0 is coming

2018

The high rate of endoreduplication in the repair deficient CHO mutant EM9 parallels a reduced level of methylated deoxycytidine in DNA

2008

It has been recently proposed that hypomethylation of DNA induced by 5-azacytidine (5-azaC) leads to reduced chromatid decatenation that ends up in endoreduplication, most likely due to a failure in topo II function [S. Mateos, I. Domínguez, N. Pastor, G. Cantero, F. Cortés, The DNA demethylating 5-azaC induces endoreduplication in cultured Chinese hamster cells, Mutat. Res. 578 (2005) 33-42]. The Chinese hamster mutant cell line EM9 has a high spontaneous frequency of endoreduplication as compared to its parental line AA8. In order to see if this is related to the degree of DNA methylation, we have investigated the basal levels of both endpoints in AA8 and EM9, as well as the effect of ext…

Modulation of Base Excision Repair Alters Cellular Sensitivity to UVA1 but not to UVB¶

2007

Abstract Oxidative DNA damage has been implicated in some of the biological properties of UVA but so far not in the acute photosensitivity or cellular sensitivity. In contrast to pyrimidine dimers, oxidative DNA damage is predominantly processed by base excision repair (BER). In order to further clarify the role of oxidative DNA damage and its repair in the acute cellular response to UV light, we studied UVA1 and UVB sensitivities in three different cell model systems with modified BER. 8-Oxoguanine-DNA-glycosylase 1–/– (OGG1–/–) mouse embryonal fibroblasts and human fibroblasts in which BER was inhibited by incubation with methoxyamine were hypersensitive to UVA1, in particular to low dose…

Cisplatin-induced endoreduplication in CHO cells: DNA damage and inhibition of topoisomerase II.

2006

It has been proposed that polyploid cells that arise during a variety of pathological conditions and as a result of exposure to genotoxicants, typically in the liver, become aneuploid through genetic instability. Aneuploidy contributes to, or even drives, tumour development. We have assessed the capacity of the drug cisplatin, one of the most commonly used compounds for the treatment of malignancies, to induce endoreduplication, a particular type of polyploidy, in cultured Chinese hamster AA8 cells. Taking into account that any interference with DNA topoisomerase II (topo II) function leads to endoreduplication, we have found that treatment of the cells with this platinum compound results i…

Diagnosis of polycystic ovary syndrome: from NIH criteria to ESHRE-ASRM guidelines.

2004

In the past, the diagnosis of polycystic ovary syndrome (PCOS) was based on National Institute of Health (NIH) criteria (hyperandrogenism and chronic anovulation) or on sonographic findings of polycystic ovaries. Diffe-rences in diagnosis criteria made it difficult to compare the data of studies coming from different countries. Moreover, there was criticism of both the methods used. In 2003, at a joint meeting of the European Society for Human Reproduction (ESHRE) and the American Society of Reproductive Medicine (ASRM), new guidelines for the diagnosis of PCOS were suggested. According to these guidelines, it is possible to reach a diagnosis of PCOS when at least 2 of these 3 elements are …

Adjuncts for ovarian stimulation: when do we adopt “orphan indications” for approved drugs?

2009

Several drugs, shown to be safe for other uses, have proven to be highly effective adjuncts for ovarian stimulation. The authors evaluate these "orphan" indications and make recommendations so that more patients will benefit from their use.

Metformin induces lipid changes on sphingolipid species and oxidized lipids in polycystic ovary syndrome women.

2019

Metformin is one of the treatments used for pcoS pathology decreasing body weight, plasma androgen, FSH and glucose levels. Unfortunately, there is little known about metformin’s effects on lipid metabolism, a crucial process in pcoS pathology. We have employed a lipidomic approach to explore alterations in the plasma lipid profile of patients with PCOS following metformin treatment. The aim is to offer new insights about the effect of metformin in PCOS patients. Plasma samples were obtained from 27 subjects prior to and following 12 weeks of metformin treatment. A detailed biochemical characterization and lipidomic profile was performed. Metformin reduces BMI, HOMA-IR, fSH and androstenedi…

Analytical Performance and Validation of a Bioassay for Thyroid-Blocking Antibodies

2016

A cell-based bioassay for the measurement of thyroid blocking autoantibodies (TBAb) has been recently reported. The analytical performance and validation of this bioassay is assessed and described.Chinese hamster ovary cells expressing a chimeric thyrotropin receptor were treated with bovine (b) TSH and different concentrations of an immunoglobulin G (IgG) monoclonal human TBAb (K1-70). TBAb was measured as a function of luciferase activity relative to bTSH alone and expressed as percent inhibition. Results obtained in the chimeric cell line were compared with those of a wild-type cell line. Analytical performance studies were subsequently performed with the chimeric cell line only.Immunode…

Comparison of a Novel Homogeneous Cyclic Amp Assay and a Luciferase Assay for Measuring Stimulating Thyrotropin-Receptor Autoantibodies.

2019

Objective: Stimulating thyrotropin-receptor antibodies (TSAb) cause Graves’ disease (GD). We tested a novel homogeneous fluorescent 3′,5′ cyclic adenine monophosphate (cAMP) assay for the detection of TSAb in a bioassay. Methods: Chinese hamster ovary (CHO) cell lines expressing either a chimeric (MC4) or wild-type (WT) TSH-R were incubated with the adenyl cyclase activator forskolin, a human TSAb monoclonal antibody (M22), and with sera from GD patients. Intracellular cAMP levels were measured using a Bridge-It® cAMP assay, and the results were compared with a luciferase-based bioassay. Results: Both cell lines were stimulated with forskolin concentrations (0.006–200 µM) in a dose-dependen…