Benzo(a)pyrene (BaP), an aryl hydrocarbon receptor (AhR) ligand present in cigarette smoke and car exhaust, is thought to have negative effects on male reproduction. We hypothesized that BaP damages sperm through AhR activation, phase I enzyme induction, DNA adduct formation, and increased germ cell apoptosis in the testis, and that resveratrol, a natural competitive inhibitor of the AhR found in some red wines, could prevent the adverse effects of BaP on sperm. Male Balb C mice were injected subcutaneously (s.
View Article and Find Full Text PDFObjective: This study investigated family functioning in adolescents with the restricting and bulimic type of anorexia nervosa (AN) and in healthy controls.
Method: Fifty-one parents and their children (17 with AN and 34 healthy adolescents) completed the Family Assessment Measure, a self-report instrument that provides information about the functional strengths and weaknesses of the family and each family member.
Results: AN patients with the bulimic subtype and their mothers were significantly more likely to perceive family functioning as impaired than were healthy adolescents or restricting AN patients.
Background: We determined whether oocyte dysmorphisms, especially repetition of specific dysmorphisms from cycle to cycle, had a prognostic impact on intracytoplasmic sperm injection (ICSI) outcome.
Methods: ICSI patients (n = 67) were grouped as follows: group 1 >50% phenotypically dysmorphic oocytes per cohort (cytoplasmic and extra-cytoplasmic dysmorphisms) with no repetition of a specific dysmorphism from cycle one to cycle two (36 cycles and 274 oocytes); group 2 >50% dysmorphic oocytes per cohort and repetition of the same dysmorphism from cycle one to cycle two (32 cycles and 313 oocytes); group 3 (control) <30% dysmorphic oocytes (33 cycles and 378 oocytes).
Results: In group 2 (repetitive), 47% of oocytes were observed to have organelle clustering versus 20.
Background: Swim-up techniques for sperm separation may have detrimental effects on sperm DNA. We wished to determine whether the normal swim-up method with centrifugation used in our laboratory, which involves a centrifugation step, was harmful to sperm compared with swim-up without centrifugation.
Methods: Semen samples were obtained from patients undergoing IVF or andrology assessment.
J Hematother Stem Cell Res
August 2001
The ex vivo expansion of hematopoietic stem cells (HSCs) is the subject of intense commercial and academic interest due to the potential of HSCs to be a renewable source of material for cellular therapeutics. Unfortunately, because methodologies have not yet been developed to grow clinically relevant numbers of HSCs (or their derivatives) consistently, the potential of this technology is limited. Manipulation of the in vitro culture microenvironment, primarily through cytokine supplementation, has been the predominant approach in studies attempting to expand primary human HSC numbers in vitro.
View Article and Find Full Text PDFPolycyclic aromatic hydrocarbons (PAHs) are toxic chemicals released into the environment by fossil fuel combustion. Moreover, a primary route of human exposure to PAHs is tobacco smoke. Oocyte destruction and ovarian failure occur in PAH-treated mice, and cigarette smoking causes early menopause in women.
View Article and Find Full Text PDFObjective: To determine the effects of chilling to 0 degrees C on the meiotic spindle of human metaphase II oocytes, as observed by optical sectioning microscopy.
Design: Laboratory study.
Setting: Academic research laboratory in a medical school.
The effect of resveratrol, an aryl hydrocarbon receptor (AhR) antagonist, known to inhibit inducible cyclooxygenase-2 (COX2) and its transcription were examined in a model of hyperalgesia induced by carrageenan in the rat. Pretreatment with resveratrol did not reverse swelling and edema, but reversed the hyperalgesia induced by local tissue injury provoked by carrageenan. This reversal, occurring at resveratrol concentrations as low as 2 mg/kg, lasted for at least 48 hours.
View Article and Find Full Text PDFObjective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.
Design: Prospective trial in infertility patients treated with CC.
Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.
Biol Psychiatry
January 2001
Background: This study was designed to compare placebo responses in men and women.
Methods: Data for 501 women and 375 men with major depressive disorder treated with placebo from seven investigational randomized double-blind trials comparing fluoxetine with placebo were analyzed. Changes in major depressive disorder symptoms with placebo administration were measured as changes in total Hamilton Depression Rating Scale scores and adverse (nocebo) effects were measured by comparing treatment-emergent signs and symptoms.
J Biol Chem
February 2001
We have identified 7-ketocholesterol (7-KC) as an endogenous modulator that inhibits transactivation by the arylhydrocarbon receptor (AhR) through competitive binding against xenobiotic ligands. 7-KC binds AhR and displaces labeled dioxin (2,3,7,8-tetrachlorodibenzo(p)dioxin (TCDD)). IC(50) is 5 x 10(-7) m in vivo and 7 x 10(-6) m in vitro.
View Article and Find Full Text PDFObjective: Comparison of two transfer catheters in an IVF program.
Design: Prospective, randomized clinical study.
Setting: A private tertiary care center for ART.
Aryl hydrocarbon receptor (AhR) ligands are environmental contaminants found in cigarette smoke and other sources of air pollution. The prototypical compound is TCDD (2,3,7, 8-tetrachlorodibenzo-p-dioxin), also known as dioxin. There is an increasing body of knowledge linking cigarette smoking to osteoporosis and periodontal disease, but the direct effects of smoke-associated aryl hydrocarbons on bone are not well understood.
View Article and Find Full Text PDFJ Pediatr Adolesc Gynecol
May 2000
Background: Increased pediatric/adolescent cancer survivor rates have enhanced awareness of long-term effects of therapy, specifically gonadal failure. Ovarian cortex cryopreservation may hold the promise of fertility for those at risk for ovarian failure due to medical therapy. The object of this study was to determine if an ovarian cryopreservation program is feasible and to define suitable candidates.
View Article and Find Full Text PDFObjective: To evaluate and compare the extent of Internet use by infertile couples attending a government-funded and a private assisted reproductive technology clinic.
Design: A prospective study.
Setting: One private and one public tertiary care fertility clinic in Toronto.
This review outlines the basic principles of a novel interrupted progestin HRT regimen in which estrogen is administered continuously, and progestin is given in a 3-days on, 3-days off pulsed fashion. The rationale for this regimen is to prevent receptor down-regulation and allow increased estrogen and progestin sensitivity during the progestin-free periods. Background information is provided including the reasons for poor patient acceptance of HRT, and the concerns of the potential association of HRT with breast and endometrial cancer.
View Article and Find Full Text PDFAryl hydrocarbon receptor (AhR) ligands such as dioxin and benzo[a]pyrene are environmental contaminants with many adverse health effects, including immunosuppression, carcinogenesis, and endothelial cell damage. We show here that a wine component, resveratrol (3,5,4'-trihydroxystilbene), is a competitive antagonist of dioxin and other AhR ligands. Resveratrol promotes AhR translocation to the nucleus and binding to DNA at dioxin-responsive elements but subsequent transactivation does not take place.
View Article and Find Full Text PDFImproved culture conditions that support the development of human embryos to the blastocyst stage in vitro led to the prospect of blastocyst transfer to increase pregnancy rates. Thus, there is a need for characterization of possible biochemical markers able to predict the implantation potential of human blastocysts. In this study, the expression of three placental markers that are expressed prior to implantation, beta-human chorionic gonadotrophin (HCG), human leukocyte antigen (HLA)-G and pregnancy specific beta-1 glycoprotein (SP-1), was investigated.
View Article and Find Full Text PDFXenogeneic transplantation of ovarian cortex into an immunodeficient animal host may be an approach toward fertility preservation for young female patients undergoing cancer therapy. Our objective was to evaluate the development of follicles in human ovarian cortex placed s.c.
View Article and Find Full Text PDFNon-obstructive azoospermia accounts for a considerable proportion of male factor infertility. Current therapies for treatment of this kind of infertility include procedures such as intracytoplasmic sperm injection (ICSI), round spermatid injection (ROSI), round spermatid nucleus injection (ROSNI) and elongated spermatid injection (ELSI). All involve injection of haploid germ cells retrieved from testicular biopsies into recipient oocytes.
View Article and Find Full Text PDFPurpose: Our purpose was to compare oocyte nuclear maturation and embryo quality after pituitary down-regulation and ovarian stimulation with highly purified follicle-stimulating hormone (FSH) or human menopausal gonadotropin (HMG).
Methods: Fifty-five patients 37 years of age or younger who were undergoing in vitro fertilization (IVF)-intracytoplasmic sperm injection (ICSI) were evaluated retrospectively. In all cases, male factor was the only indication for treatment, with no female-related factors identified.
Objective: To determine whether there is a maximal value for endometrial thickness, as measured on the day of hCG administration, above which implantation and pregnancy are unlikely to occur.
Design: Retrospective analysis.
Setting: A university-based tertiary care center for assisted reproductive technology.