Publications by authors named "Gary N Clarke"

Objective: To describe the clinical outcomes for all HIV-serodiscordant couples attending an assisted reproduction program.

Design, Setting And Participants: Retrospective review of demographic, clinical and outcome data for all HIV-serodiscordant couples who attended an assisted reproduction program at a tertiary hospital in Melbourne, between its commencement in 2003 and June 2010.

Main Outcome Measures: Pregnancies, miscarriages, births, HIV transmission to the HIV-negative partner, semen quality and detection of HIV (HIV RNA and HIV DNA) in semen.

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Sperm immunity in females can reduce the likelihood of natural conception, and sperm antibodies from female sera have been shown to inhibit IVF in humans and in several animal models. The etiology of sperm immunity in human females is unknown, but several possible mechanisms have been proposed, including cross-reactivity with microbial antigens and interferon gamma-mediated potentiation of the antisperm immune response in women whose male partners have sperm autoantibodies in their semen. This article reviews these ideas and postulates a novel hypothesis based on the potential for the generation of anti-idiotype antibodies in women whose partners have sperm antibodies in their semen.

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Six donor semen samples were evaluated after 28 years cryopreservation in liquid nitrogen. The results showed that the samples retained good postthaw motility recovery and normal levels of binding to the human zona pellucida and that four of the five samples tested also gave normal levels of zona-induced acrosome reaction. In conclusion, human sperm can survive very long-term storage, which is pertinent information for clinicians referring boys and young men for sperm banking before chemotherapy.

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Previous investigations have demonstrated the propensity of strong IgA-class sperm autoantibodies to impede fertilization. However, because there has not been a general consensus on this issue, the aim of this retrospective analysis was to focus on the effects of different levels of IgA-class antibodies on each stage of the IVF procedure. This study has confirmed that high level IgA class antibodies significantly reduce fertilization rates but, unexpectedly, also has shown a very significant improvement in embryo implantation rates in patients with weak to moderate antibody levels.

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Louise Brown, the first baby conceived after IVF, was born on 25 July 1978 and turned 27 last year. From one perspective, her birth can be seen as the culmination of 300 years of medical and scientific investigation aimed at understanding the fascinating process of reproduction. This essay was written as a tribute to mark the unique contribution to assisted reproductive technology (ART) which resulted from the collaboration of a scientist, Bob Edwards, and a clinician, Patrick Steptoe, who pioneered the successful clinical use of IVF.

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The aim of this study was to evaluate the sperm-immobilizing properties of lemon juice to determine if they are consistent with its traditional contraceptive use. It was found that lemon juice supernatant (LJS) has high osmolality (550-60 mOsm) and low pH (2.2-2.

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To compare sperm counts for two groups of men who had presented for infertility investigations approximately 20 years apart. The study compared results for 309 men tested between 1977 and 1981 with those of 559 men tested between 1997 and 1998 using identical methodology. In order to approximate the normal population, only those men with counts above 5 million/mL were included in the final analysis.

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Improved prediction of male fertility requires advances in semen analysis. This study examined the reproducibility and independence of the flow cytometry acridine orange test (FCM-AOT) of sperm chromatin integrity as an assessment of semen quality. The study found that FCM-AOT results are not significantly affected by up to 6 h delay in semen preparation (n = 9) or contamination of semen with moderate concentrations of bacteria (<10(8)/ml E.

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Semen analysis is the most important laboratory investigation for men when assessing the infertile couple. Advances in in vitro fertilisation (IVF) techniques, particularly intracytoplasmic sperm injection (ICSI) involving the direct injection of a single spermatozoon into an egg, have not diminished the role of semen analysis in modern reproductive practice. Semen analysis is the most basic laboratory investigation undertaken and is descriptive in terms of semen volume, appearance, viscosity, sperm concentration, sperm motility and morphology.

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Background: With HIV-1-infected individuals now facing the prospect of relatively long and healthy lives, many discordant couples (where the male is HIV-1 seropositive) are seeking to have children. To assist reducing the risks of heterosexual and subsequent vertical transmission in this situation, quantification of HIV-1 viral load in seminal plasma may be effective as one of several measures to reduce the risk of infecting the mother during insemination, potentially providing a better indication of infectivity than blood plasma analysis.

Objective(s): To modify existing molecular methods for the purpose of analysing HIV-1 viral load in seminal plasma.

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