Publications by authors named "Christoph Keck"

Nausea and vomiting of pregnancy (NVP) is among the most common conditions that pregnant women encounter in the early stages of pregnancy. It can affect up to 85% of pregnant women, thus representing a significant public health concern. NVP results in substantial negative physical, emotional, and financial consequences.

View Article and Find Full Text PDF

The 1,4-dithiin motif is known for its reversible redox properties to generate radical cations and diradical dications and thus is interesting for organic electronic applications. However, examples where this motif is embedded into chiral larger fused aromatic compounds are very rare. Here we describe the syntheses of several structurally related pyrene fused dithiins and their spectroscopic investigations with a focus on tuning circular dichroism, with respect to the g values, depending on their connectivity.

View Article and Find Full Text PDF

Objective: To investigate safety and effectiveness of NOMAC-E2 and levonorgestrel-containing COCs (COC) in users over 40.

Methods: In this large, observational study, new users of NOMAC-E2 and COC were recruited in Europe, Australia, and Latin America and followed-up questionnaires. Incidence of venous thromboembolism (VTE) was expressed as incidence rate (IR; events/10 women-years [WY]).

View Article and Find Full Text PDF

To investigate unintended pregnancy and changes in mood, acne, and weight in NOMAC-E2 vs levonorgestrel-containing COC (COC) users under 25 years. In this large, observational study, new users (first-ever users of an eligible COC or restarting with the same or a new eligible COC after a break of at least 2 months) of NOMAC-E2 and COC were recruited in 12 countries in Europe, Australia, and Latin America and followed up questionnaires for up to 2 years. Unintended pregnancy was expressed by the Pearl Index (PI; contraceptive failures/100 women-years).

View Article and Find Full Text PDF

Background: Chromosomal instability, a hallmark of cancer, results in changes in the copy number state. These deviant copy number states can be detected in the cell-free DNA (cfDNA) and provide a quantitative measure of the ctDNA levels by converting cfDNA next-generation sequencing results into a genome-wide copy number instability score (CNI-Score). Our aim was to determine the role of the CNI-Score in detecting epithelial ovarian cancer (EOC) and its role as a marker to monitor the response to treatment.

View Article and Find Full Text PDF

Background: The use of recombinant human follicle-stimulating hormone (r-hFSH) in ovarian stimulation protocols for infertility treatment in assisted reproductive technology (ART) clinical practice is well established. More recent advancements include the availability of biosimilar r-hFSH products, which expand the choices available to healthcare practitioners and patients. Better understanding of how such a product contributes to routine clinical practice is valuable to help prescribers make informed treatment choices.

View Article and Find Full Text PDF

Donor-acceptor (D-A) dyes constitute one of the fundamental structural motifs of functional organic materials. In most cases, the donor and acceptor moieties are connected by a single bond, which could potentially be replaced by a fused aromatic ring to enhance the rigidity and conjugation of the dye moieties. However, there is still a lack of synthetic methodologies for such fused D-A systems.

View Article and Find Full Text PDF

Background: Subacute thyroiditis (SAT) is a rare inflammatory disease that presents diagnostic challenges. The underlying pathophysiology and prediction of outcomes are elusive. We investigated the long-term follow-up of SAT for up to 30 years and determined predictors for later hypothyroidism.

View Article and Find Full Text PDF

Background: Autoimmune thyroiditis (AIT) has been found to be associated with polycystic ovary syndrome (PCOS). The aim of this retrospective cohort study using data from a fertility clinic, with patients recruited from 2009 to 2010, was to confirm the higher prevalence of AIT in PCOS and to evaluate the impact of AIT on reproductive and metabolic parameters of PCOS patients.

Methods: Patients comprised 827 PCOS subjects seen for reproductive or metabolic complaints.

View Article and Find Full Text PDF

Introduction: The corpus luteum (CL), develops from the ruptured follicle after gonadotropin stimulation. Based on intracellular reorganization of the cytoskeleton an human chorionic gonadotropin (hCG) dependent sprouting and migration of luteinizing granulosa cells (LGCs) and endothelial cells is observed. Rho-GTPases are shown to be key regulators of cytoskeletal restructuring.

View Article and Find Full Text PDF

The objective of this study was to investigate the effect of metformin versus acarbose in terms of ovulation rate, their impact on hormonal and metabolic status and tolerability of both drugs in patients with polycystic ovary syndrome (PCOS). Seventy-five patients with PCOS were included in this prospective randomised controlled double-blinded clinical study. According to randomisation, patients were allocated to receive either metformin 2550 mg/day (n = 37) or acarbose 300 mg/day (n = 38) for 12 weeks.

View Article and Find Full Text PDF

Problem: To investigate whether polymorphisms in the interleukin-1beta (IL-1beta) gene are associated with uterine leiomyoma.

Method Of Study: Case-control study in a collective of 131 patients and 280 controls. Genotyping of the IL-1beta-511 and IL-1beta-3954 polymorphism was performed by PCR amplification and subsequent RFLP analysis.

View Article and Find Full Text PDF

Background: Genetic factors may play a role in male infertility.

Methods: In a prospective case-control study, we assessed the allele and genotype frequencies of the TNFalpha -308 C-->T and -863 C-->A polymorphisms, detected by PCR of sperm DNA, of 577 Caucasian men recruited in an infertility clinic. Semen sampling was performed and spermiogram results were correlated to genetic data.

View Article and Find Full Text PDF

The growth and development of the corpus luteum (CL) is regulated by gonadotropic hormones. It is formed by granulosa cells (GCs), theca cells, and endothelial cells, and is the primary source of circulating progesterone. During early pregnancy only human chorionic gonadotropin (hCG) but not luteinizing hormone (LH) extends the life span of the CL, although hCG and LH interact with the same receptor and have similar actions on the CL.

View Article and Find Full Text PDF

Ovarian stimulation is an integral part of assisted reproduction treatments. Ovarian response to gonadotrophin treatment, besides other factors, determines the outcome of treatment, as the number and quality of oocytes retrieved are related to the chance of achieving a pregnancy. A number of factors have been identified that might predict ovarian response, such as age of the patient and antral follicle count.

View Article and Find Full Text PDF

Although many IVF centers have implemented a Quality Management System, staff management in the IVF laboratory is still highly neglected. This article describes methods for staff development and monitoring of staff performance in the IVF laboratory.

View Article and Find Full Text PDF

Objective: Genetic as well as hormonal factors are known to influence the development and clinical course of endometriosis. We aimed to investigate the association among 10 single nucleotide polymorphisms (SNPs) involved in the estrogen metabolism and endometriosis and to develop a multiple genetic model.

Methods: In a case-control study, we investigated the genotype frequencies of 10 estrogen metabolizing SNPs in 32 patients with endometriosis and 790 healthy controls using sequencing-on-chip-technology with solid-phase polymerase chain reaction on oligonucleotide microarrays: catechol-O-methyltransferase, Val158Met G->A, 17-beta-hydroxysteroid dehydrogenase type 1 (HSD17), vlV A->C, cytochrome P450 (CYP), 17 A2 allele T->C, CYP1A1 MspI RFLP T->C, CYP1A1 Ile462Val A->G, CYP19 Arg264Cys C->T, CYP19 C1558T C->T, CYP 1B1 Leu432Val, CYP1B1 Asn453Ser, and estrogen receptor alpha IVS1 -401>C.

View Article and Find Full Text PDF

Objective: To evaluate the association between the presence of uterine leiomyoma and two single nuclear polymorphisms of the p53 tumor suppressor and the angiopoietin-2 (ANGPT2) genes.

Design: Prospective case control study.

Setting: Academic research institution.

View Article and Find Full Text PDF

Objective: Genetic factors have been proposed as modulators of the timing of natural menopause. Single nucleotide polymorphisms (SNPs) of genes associated with thrombophilia and vascular homeostasis may interfere with ovarian function and thus are candidate genes for early menopause. We attempted to assess the association of SNPs and the timing of menarche and natural and surgical menopause in an ethnically homogenous cohort of Middle European white women.

View Article and Find Full Text PDF

The aims of this study were [1] to test the feasibility of autologous heterotopic transplantation of large ovarian tissue samples (approximately 2 cm in diameter and 2 or 3 mm thick) without vascular anastomosis and [2] to compare follicle count and microvessel density in fresh and grafted 2-mm vs. 3-mm tissue samples in an animal model. After transplantation, we observed regular menstrual cycles and ovulation proved by high E(2) levels and intermittent P peaks in all Suffolk sheep, and histologic examination revealed no statistically significant differences in the number of primordial follicles and microvessel density between samples 2 mm and 3 mm in diameter.

View Article and Find Full Text PDF

Background: The p53 tumour suppressor gene is a well-known factor regulating apoptosis in a wide variety of cells and tissues. Alterations in the p53 gene are among the most common genetic changes in human cancers. In addition, recent data provide evidence that p53 plays a critical role in mediating pregnancy by regulating steroid hormone activation.

View Article and Find Full Text PDF

Genetic thrombophilia has been established as a risk factor for pregnancy-associated disorders, such as thrombosis, early and late miscarriage, and pre-eclampsia. Associations between the factor V (F5) Leiden G1691A and the prothrombin/factor II (F2) G20210A SNPs and pre-eclampsia have been evaluated in over 50 association studies. A pooled analysis of 23 and 11 studies demonstrates that carriage of the F5 Leiden G1691A (p < 0.

View Article and Find Full Text PDF

Objective: To summarize the existing experience with the use and success rate of assisted reproductive techniques (ART), in particular testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI), in Klinefelter patients.

Design: A systematic review of the literature, including all published case reports to date.

Patient(s): Thirty-nine reported successful pregnancies fathered by nonmosaic Klinefelter patients.

View Article and Find Full Text PDF