[Oxidation and female reproduction: the good, the bad and what's between].

Reactive oxygen and nitrogen species constitute an inseparable part of aerobic life on earth. They have been known to science for about 90 years, but only during the last 50 years research in this field has expanded. Initially, scientists focused on the free radicals-induced damage to biological systems.

Oxidative parameters of embryo culture media may predict treatment outcome in in vitro fertilization: a novel applicable tool for improving embryo selection.

Objective: To examine whether the oxidative status of an individual embryo before transfer may predict chances of implantation.

Design: A prospective laboratory study.

Setting: An IVF unit in a university-affiliated hospital.

Oxidative stress indices in follicular fluid as measured by the thermochemiluminescence assay correlate with outcome parameters in in vitro fertilization.

Objective: To evaluate oxidative stress indices in follicular fluid (FF) by a novel thermochemiluminescence (TCL) assay and investigate the correlation between TCL and i.v.f.

Early embryo-endometrial signaling modulates the regulation of matrix metalloproteinase-3.

Objective: To examine matrix metalloproteinase-3 (MMP-3) expression in human stromal cell culture after P stimulation and the effect of conditioned medium from human embryo-epithelial cells coculture on its expression and activity.

Design: Metabolic and endocrine studies on human tissue.

Setting: In vitro fertilization (i.

Oxidative stress indices in seminal plasma, as measured by the thermochemiluminescence assay, correlate with sperm parameters.

Objective: To examine the effect of oxidation of proteins and lipids, as measured by a novel thermochemiluminescence (TCL) analyzer, and to evaluate the correlation between TCL indices in seminal plasma and sperm parameters.

Design: Experimental and prospective clinical studies.

Setting: An infertility unit.

Analyzing factors affecting the success rate of frozen-thawed embryos.

Purpose: In recent years the infertile population applying for IVF treatments was changed and so the indications for performing intracellular sperm injection (ICSI). The aim of this study was to analyze predicting factors of our thawing cycles.

Methods: From December 1998 to July 2001, 440 consecutive thawing cycles were performed.

A prospective randomized controlled study of the effect of short coincubation of gametes during insemination on zona pellucida thickness.

A prospective, randomized study was conducted to evaluate the thickness, of zona pellucida (ZP) after brief or standard exposure of human oocytes to spermatozoa, and to determine the correlation between ZP thickness, fertilization rate and embryo quality. The mean ZP thickness 48 h after insemination was found to be significantly less in fertilized oocytes than in non-fertilized oocytes in all treated groups (13.72 +/- 3.

The impact of cigarette smoking on zona pellucida thickness of oocytes and embryos prior to transfer into the uterine cavity.

Background: Smoking has been reported to promote infertility. The zona pellucida plays an important role in fertilization and implantation. We report, for the first time, the effect of cigarette smoking on zona pellucida thickness of oocytes and embryos as one of the factors that may interfere with fertility.

The impact of early testicular sperm extraction or cryopreservation on the outcome of intracytoplasmic sperm injection--a randomized controlled study.

Purpose: To compare the outcome of sperm extraction 24 h before ovum pickup and on the day of oocyte retrieval.

Methods: A controlled study was performed to compare the outcome of 90 sperm extractions and in vitro sperm injection cycles performed in 54 patients.

Results: Available fresh sperm for the sperm injection procedure and cryopreservation obtained on the day of ovum pickup were similar to sperm collected 1 day before (33.

Decreased expression of tissue inhibitor of matrix metalloproteinases in follicular fluid from women with polycystic ovaries compared with normally ovulating patients undergoing in vitro fertilization.

Objective: To compare activity of matrix metalloproteinases (MMP) and expression of their tissue-specific inhibitor (TIMP) in the follicular fluid of normally ovulating women and women with the polycystic ovary syndrome (PCOS).

Design: Prospective study.

Setting: IVF unit and endocrine research unit.

The value of sperm pooling and cryopreservation in patients with transient azoospermia or severe oligoasthenoteratozoospermia.

Background: A transient state of azoospermia may occur due to toxic, environmental, infectious or iatrogenic conditions. Finding sperm in the ejaculate of such patients is often unpredictable and may be critical in IVF treatment. In the present study, the approach of pooling and cryopreservation of sperm is evaluated.

The hypotransferrinaemic mouse: ultrastructural and laser microprobe analysis observations.

Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice.

Deferoxamine-induced iron mobilization and redistribution of myocardial iron in cultured rat heart cells: studies of the chelatable iron pool by electron microscopy and Mössbauer spectroscopy.

Iron mobilization by deferoxamine from iron-loaded rat heart cells in culture was studied by electron microscopy and Mössbauer spectroscopy to identify the chelatable iron pool. Studies in which iron 59 was used have shown a diminishing response to deferoxamine with increasing time intervals, which suggests a gradual transit from a more available to a less available storage iron compartment. Mössbauer spectroscopy showed that practically all iron mobilized by deferoxamine was derived from the small (less than 3.

Neuroblastomas contain iron-rich ferritin.

The ultrastructure of neuroblastoma was examined using unstained sections so that ferritin particles could be identified by the electron density of their iron cores. Ferritin and hemosiderin were found in ten of 11 neuroblastomas that were examined when the patients first presented. The study was therefore expanded to an additional group of children, including some diagnosed by noninvasive procedures and given chemotherapy before the excision of their tumors.

Juvenile acid maltase deficiency presenting as paravertebral pseudotumour.

In addition to the infantile lethal form of glycogen storage disease with cardiomyopathy (GSD Type IIa, Pompe disease) 1,4 glucosidase or acid maltase deficiency has been reported in a few children and adults (GSD Type IIb or IIc) erroneously thought to have muscular dystrophies. The clinical heterogeneity of the muscle involvement in these latter cases is illustrated in a 12-year-old boy presenting with a right lumbar mass, growth retardation, muscular weakness including difficulty in walking, and marked elevations of muscle and liver enzymes. Light- and electron-microscopic examination of specimens from the lumbar mass, apparently normal skeletal muscle and liver, showed typical changes consistent with the biochemical and enzymatic features of acid maltase deficiency.

The influence of cryopreservation on the ultrastructural morphology of human thyroid cells.

The purpose of this study was to investigate the effects of the freeze-thaw procedure on the ultrastructural features of human thyroid cells. Four different stages of thyroid cell preparation were compared: (1) fresh surgical tissue, serving as control, (2) cell suspension before freezing, (3) cell suspension after thawing, and (4) monolayer cell culture, obtained from cells after thawing. Electron microscopic examination of cells from each stage showed that the freeze-thaw procedure used caused only minor intracellular alterations restricted to mitochondria.

Intestinal mucosa in nephropathic cystinosis.

The major manifestations of nephropathic cystinosis are renal tubular acidosis, vitamin D-resistant rickets, and dwarfism. Cystine crystals are deposited in a variety of cells, mainly phagocytic, including macrophages of the intestinal lamina propria. Previously, ultrastructural changes were suggested to occur in the absorptive epithelium as well, possibly as a result of local cystine toxicity.

Ultrastructural pathology of iron-loaded rat myocardial cells in culture.

The pathological changes induced by in-vitro iron-loading or cultured rat myocardial cells were studied. Cells were exposed to 59Fe-labelled ferric ammonium citrate for up to 24 h followed by 24-72 h chase experiment. After 24 h exposure 29% of the total cellular radioactivity was found in ferritin, 10% in non-ferritin heat supernatant and 61% in an insoluble heat-precipitable form.

Hepatomegaly following short-term high-dose steroid therapy.

Children treated with large doses of corticosteroids were found to develop hepatomegaly within a few days. No relationship could be established between the condition for which steroids were given and the liver enlargement. Liver biopsy was thought to be indicated, and thus was performed in three children because of diagnostic uncertainty.