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Featured researches published by C. Janssenswillen.


Fertility and Sterility | 1997

The effect of propofol on parthenogenetic activation, in vitro fertilization and early development of mouse oocytes

C. Janssenswillen; Frank Christiaens; F. Camu; André Van Steirteghem

OBJECTIVE To assess the effect of propofol on fertilization and early embryo development in a mouse IVF model. DESIGN Controlled study. SETTING Mouse IVF. INTERVENTION(S) Mouse oocytes were exposed in vitro to propofol at a concentration of 0 (control), 50, 250, 500, 1,000, or 5,000 ng/mL for 30 minutes, washed, and inseminated. Thereafter, fertilization was assessed. Subsequent in vitro development to the blastocyst stage was monitored daily. The potential to activate parthenogenetically oocytes also was evaluated by looking for spontaneous extrusion of the second polar body or development to the two-cell stage. In a second step, a pure propofol solution was added to culture medium and used as a standard. MAIN OUTCOME MEASURE(S) Two-cell and blastocyst-stage embryo. RESULT(S) Where fertilization occurred, subsequent embryo cleavage and development up to the blastocyst stage was affected significantly by the presence of propofol solution in the medium, (i.e., 3% to 41%) in comparison with the control group (76%). Exposure of unfertilized oocytes for 30 minutes to propofol results in a parthenogenetic activation of 33% to 60%, which was significantly higher than the control (10%). When oocytes were kept in propofol for 24 hours, a mean of 30% of activation was observed as compared with 0.5% for the control. CONCLUSION(S) We can conclude from these experiments that even a brief exposure of cumulus-enclosed oocytes to a low concentration of propofol is deleterious to subsequent cleavage. Exposure of unfertilized oocytes to propofol results in a high degree of parthenogenetic activation.


Journal of Inherited Metabolic Disease | 1996

Review: Preimplantation diagnosis of inherited disease

Willy Lissens; Karen Sermon; Catherine Staessen; E. Van Assche; C. Janssenswillen; H. Joris; A. Van Steirteghem; I. Liebaers

SummaryPreimplantation diagnosis of inherited diseases has become possible with the techniques ofin vitro fertilization, blastomere biopsy of the 6- to 10-cell embryo and DNA analysis of the single blastomeres. Disease-free embryos are selected for transfer to the uterus, thereby avoiding the need for termination of a fetus diagnosed as affected in prenatal diagnosis in the first or early-second trimester of pregnancy. The genetic indications for preimplantation diagnosis are theoretically the same as for prenatal diagnosis, but the defects must be detectable by the polymerase chain reaction. For X-linked recessive diseases, fluorescencein situ hybridization can be used as an alternative for the selection of female embryos. So far almost 40 healthy children have been born worldwide after preimplantation diagnosis for genetic disease. The possibilities and limitations of preimplantation diagnosis, especially in prevention of inherited disease, are discussed in this review.


Journal of Reproductive Immunology | 1994

The effect of pentoxifylline on in-vitro fertilization in the presence of anti-sperm antibodies

Greta Verheyen; Herman Tournaye; C. Janssenswillen; Pascale Henderix; Paul Devroey; André Van Steirteghem

In cases of severe immunological male-factor infertility, impairment of spermatozoal motility and of acrosome reaction resulting in reduced fertilization capacity have been described by several authors. The present study investigated the use of pentoxifylline in enhancing in-vitro fertilization (IVF) in the presence of anti-sperm antibodies. Thirty-seven IVF cycles were conducted in 28 different couples suffering from immunological male-factor infertility with at least 50% antibody-coated spermatozoa. Sibling oocytes were inseminated at random with spermatozoa incubated with or without 3.6 mM pentoxifylline after selection by a Percoll gradient. No difference in motility of the final sperm preparations was observed prior to insemination. Fertilization rate, cleavage rate and embryo quality were similar in both treatment and control groups. Nine out of ten pregnancies were achieved after the replacement of embryos both from the treatment and control group. Although pentoxifylline is known to enhance motility in-vitro and to promote induced acrosomal loss, its indiscriminate use failed to improve IVF performance in patients with anti-sperm antibodies. Further research may be necessary in order to elucidate whether a given subpopulation of these patients may benefit from a selective application of pentoxifylline.


Human Reproduction | 1993

Higher success rate by intracytoplasmic sperm injection than by subzonal insemination. Report of a second series of 300 consecutive treatment cycles

André Van Steirteghem; Jiaen Liu; H. Joris; Zsolt Nagy; C. Janssenswillen; Herman Tournaye; Marie-Paule Derde; Elvire Van Assche; Paul Devroey


Human Reproduction | 1995

Andrology: Results of 55 intracytoplasmic sperm injection cycles in the treatment of male-immunological infertility

Zsolt P. Nagy; Greta Verheyen; J. Liu; H. Joris; C. Janssenswillen; A. Wisanto; Paul Devroey; A. Van Steirteghem


Human Reproduction | 1998

Timing of oocyte activation, pronucleus formation and cleavage in humans after intracytoplasmic sperm injection (ICSI) with testicular spermatozoa and after ICSI or in-vitro fertilization on sibling oocytes with ejaculated spermatozoa.

Z.P. Nagy; C. Janssenswillen; Ronny Janssens; A. De Vos; C. Staessen; H. Van de Velde; A. Van Steirteghem


Human Reproduction | 1998

Results of intracytoplasmic sperm injection with ejaculated, fresh and frozen-thawed epididymal and testicular spermatozoa.

A. Van Steirteghem; P. Nagy; H. Joris; C. Janssenswillen; Catherine Staessen; Greta Verheyen; Michel Camus; Herman Tournaye; Paul Devroey


Human Reproduction | 1993

Cytogenetic and morphological observations of single pronucleated human oocytes after in-vitro fertilization

Catherine Staessen; C. Janssenswillen; Paul Devroey; A. Van Steirteghem


Human Reproduction | 1995

Fertilization and early embryology: Maturation of human cumulus-free germinal vesiclestage oocytes to metaphase II by coculture with monolayer Vero cells

C. Janssenswillen; Zsolt P. Nagy; A. Van Steirteghem


Human Reproduction | 1998

Comparison of assisted reproductive technology performance after oocyte retrieval under general anaesthesia (propofol) versus paracervical local anaesthetic block: a case-controlled study.

Frank Christiaens; C. Janssenswillen; A. Van Steirteghem; Paul Devroey; Christian Verborgh; F. Camu

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Paul Devroey

Vrije Universiteit Brussel

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F. Camu

Free University of Brussels

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Frank Christiaens

Vrije Universiteit Brussel

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H. Joris

Vrije Universiteit Brussel

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Herman Tournaye

Vrije Universiteit Brussel

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C. Staessen

VU University Amsterdam

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Greta Verheyen

Vrije Universiteit Brussel

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