95 results on '"Ford WC"'
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2. MENTAL HYGIENE IN INDUSTRY
- Author
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Ford Wc
- Subjects
medicine.medical_specialty ,Mental Health ,Occupational hygiene ,business.industry ,Family medicine ,Mental hygiene ,medicine ,General Medicine ,business ,Mental health ,Occupational Health ,Occupational safety and health - Published
- 1954
3. The Effect of Optic Nerve Sheath Fenestration on Intraocular Pressure in Patients With Idiopathic Intracranial Hypertension.
- Author
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Mullen M, Scofield-Kaplan SM, Ford WC, and Mancini R
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- Acetazolamide therapeutic use, Humans, Intraocular Pressure, Optic Nerve surgery, Retrospective Studies, Eye Diseases, Pseudotumor Cerebri complications, Pseudotumor Cerebri diagnosis, Pseudotumor Cerebri surgery
- Abstract
Background: To evaluate the change in intraocular pressure (IOP) in patients with idiopathic intracranial hypertension (IIH) who underwent optic nerve sheath fenestration (ONSF) and to determine if radiographic evidence of posterior scleral or globe indentation influenced IOP., Methods: This is a retrospective analysis of IOP in IIH patients who underwent ONSF. The study included all patients from September 2010 to March 2018 operated on by a single surgeon (R.M.). IOPs preoperatively and postoperatively were recorded along with the acetazolamide dosage and whether there was evidence of posterior scleral or globe indentation on preoperative MRI., Results: A total of 29 patients (35 eyes) with IIH underwent ONSF. The average reduction in IOP among all patients was 1.24 mm Hg (P = 0.0218), but this increased to 2.69 mm Hg (P = 0.004) in patients who were maintained on the same dosage of acetazolamide in the preoperative and postoperative period. Furthermore, the reduction in IOP in those with posterior scleral or globe indentation was 2.5 mm Hg (P = 0.0095). When the perioperative period was evaluated, the mean decrease in IOP was 1.83 mm Hg (P = 0.0217)., Conclusions: Reducing the cerebral spinal fluid pressure (CSFP) at the level of the intraorbital optic nerve through an ONSF can slightly reduce the IOP. In those with evidence of posterior globe or scleral indentation/flattening, the reduction in IOP was higher, which supports the theory that CSF pressure indents the globe and leads to an increase in IOP. Although these changes in IOP are small, this study provides further evidence for a connection between IOP and CSFP., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by North American Neuro-Ophthalmology Society.)
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- 2022
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4. Complex decay dynamics of HIV virions, intact and defective proviruses, and 2LTR circles following initiation of antiretroviral therapy.
- Author
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White JA, Simonetti FR, Beg S, McMyn NF, Dai W, Bachmann N, Lai J, Ford WC, Bunch C, Jones JL, Ribeiro RM, Perelson AS, Siliciano JD, and Siliciano RF
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- CD4-Positive T-Lymphocytes drug effects, Cells, Cultured, DNA, Viral drug effects, Humans, Longitudinal Studies, Viral Load drug effects, Virus Latency drug effects, Virus Replication drug effects, Anti-Retroviral Agents pharmacology, HIV Infections drug therapy, HIV-1 drug effects, Proviruses drug effects, Virion drug effects
- Abstract
In persons living with HIV-1 (PLWH) who start antiretroviral therapy (ART), plasma virus decays in a biphasic fashion to below the detection limit. The first phase reflects the short half-life (<1 d) of cells that produce most of the plasma virus. The second phase represents the slower turnover ( t
1/2 = 14 d) of another infected cell population, whose identity is unclear. Using the intact proviral DNA assay (IPDA) to distinguish intact and defective proviruses, we analyzed viral decay in 17 PLWH initiating ART. Circulating CD4+ T cells with intact proviruses include few of the rapidly decaying first-phase cells. Instead, this population initially decays more slowly ( t1/2 = 12.9 d) in a process that largely represents death or exit from the circulation rather than transition to latency. This more protracted decay potentially allows for immune selection. After ∼3 mo, the decay slope changes, and CD4+ T cells with intact proviruses decay with a half-life of 19 mo, which is still shorter than that of the latently infected cells that persist on long-term ART. Two-long-terminal repeat (2LTR) circles decay with fast and slow phases paralleling intact proviruses, a finding that precludes their use as a simple marker of ongoing viral replication. Proviruses with defects at the 5' or 3' end of the genome show equivalent monophasic decay at rates that vary among individuals. Understanding these complex early decay processes is important for correct use of reservoir assays and may provide insights into properties of surviving cells that can constitute the stable latent reservoir., Competing Interests: Competing interest statement: Aspects of the IPDA are the subject of patent application PCT/US16/28822 filed by Johns Hopkins University with R.F.S. as an inventor and licensed to AccelevirDx. R.F.S. holds no equity interest in AccelevirDx., (Copyright © 2022 the Author(s). Published by PNAS.)- Published
- 2022
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5. Foreign-Body Granulomata Caused by Injected Permanent Filler Masquerading as Cutaneous Sarcoidosis.
- Author
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Scofield-Kaplan SM, Patel SY, Mueller A, Ford WC, Evers BM, Hogan RN, and Mancini R
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- Aged, Collagen administration & dosage, Diagnosis, Differential, Female, Granuloma, Foreign-Body diagnosis, Granuloma, Foreign-Body surgery, Humans, Injections, Intralesional, Ophthalmologic Surgical Procedures methods, Polymethyl Methacrylate administration & dosage, Tomography, X-Ray Computed, Collagen adverse effects, Granuloma, Foreign-Body chemically induced, Polymethyl Methacrylate adverse effects, Sarcoidosis diagnosis
- Abstract
Foreign-body granuloma formation following filler injections is most commonly seen with permanent fillers; these reactions can occur years following the injections and often require either an intralesional steroid injection or surgical excision. The authors present a case of a 75-year-old woman with a history of systemic sarcoidosis previously treated with numerous immunosuppressive medications who was examined for bilateral infraorbital nodules and swelling that were unresponsive to treatment. She underwent a bilateral anterior orbitotomy through a transconjunctival approach with mass excision. The histologic analysis was consistent with foreign-body granulomata juxtaposed to implantable material, specifically ArteFill, which was injected many years prior. There were no separate noncaseating granulomas to suggest sarcoidosis as the underlying etiology. It is important to consider prior filler injections in patients with sarcoidosis who present with subcutaneous nodules as this changes management and may prevent the need for more aggressive immunosuppressive treatment.
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- 2019
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6. Epididymal specific, selenium-independent GPX5 protects cells from oxidative stress-induced lipid peroxidation and DNA mutation.
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Taylor A, Robson A, Houghton BC, Jepson CA, Ford WC, and Frayne J
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- Animals, CHO Cells, Cell Membrane enzymology, Cell Membrane metabolism, Cell Survival, Cricetinae, Cricetulus, Epididymis cytology, Epididymis metabolism, Exocytosis, Exosomes metabolism, Glutathione Peroxidase genetics, Guanine analogs & derivatives, Guanine metabolism, Male, Protein Transport, Rats, Recombinant Proteins metabolism, Spermatozoa cytology, Spermatozoa metabolism, Down-Regulation, Epididymis enzymology, Glutathione Peroxidase metabolism, Lipid Peroxidation, Mutation, Oxidative Stress, Spermatozoa enzymology
- Abstract
Study Question: Can selenium (Se) independent, epididymal-specific glutathione peroxidase 5 (GPX5) protect CHO-K1 cells from oxidative damage and, more specifically, from lipid peroxidation and DNA mutation?, Summary Answer: CHO-K1 cells expressing GPX5 have increased resistance to oxidative challenge and, more specifically, decreased levels of lipid peroxidation and decreased levels of the downstream DNA lesion 8-oxo-7,8-dihydroguanine (8-oxodG) compared with control cells., What Is Known Already: GPX5 associates with sperm during transit of the epididymis, and has been postulated to protect sperm from peroxide-mediated attack. However, its function as an active glutathione peroxidase has been questioned due to substitution of the classical selenocysteine residue at its active site. Indirect evidence for a functional role for GPX5 has been provided by in vivo studies, in particular from the GPX5 knockout mouse whereby offspring sired by GPX5(-/-) males have a higher rate of spontaneous abortion and developmental defects, attributed to increased oxidative injury (8-oxodG) to sperm DNA, but only when the GPX5(-/-) males are over 1 year of age. Interestingly, we have previously shown severely reduced levels of GPX5 in humans., Study Design, Size, Duration: To look more directly at its role in protection against oxidative damage, we have used an in vitro system, generating a CHO-K1 mammalian cell line expressing recombinant rat GPX5., Participants/materials, Setting, Methods: We have used the recombinant CHO-K1 cells to determine whether GPX5 is able to protect these cells from an administered oxidative challenge, using a range of approaches. We compared the viability of GPX5-expressing cells with control cells by both MTT and trypan blue exclusion assays. We next investigated whether GPX5 protects the cells specifically from lipid peroxidation, by using the fluorescent reporter molecule C11-BODIPY(581/591), and thus from downstream DNA mutation, by comparing levels of the DNA lesion 8-oxodG. We also investigated whether GPX5 can be transferred to rat sperm via epididymosomes., Main Results and the Role of Chance: GPX5-expressing CHO-K1 cells had increased viability compared with control cells following oxidative challenge (P < 0.005). We also found that GPX5-expressing CHO-K1 cells had significantly lower levels of C11-BODIPY(581/591) oxidation, and hence lipid peroxidation, compared with control cells. Levels of 8-oxodG DNA damage were also markedly lower in the nuclei of GPX5-expressing cells than in control cells. Finally, we showed that GPX5 can be transferred to rat sperm via epididymosomes., Limitations, Reasons for Caution: GPX5 is not active in glutathione peroxidase assays using H₂O₂ as the substrate. However, the related non-mammalian Se-independent GPXs show preference for electron donors other than glutathione, with a number utilizing thioredoxin as a reducing equivalent. Hence, the in vitro activity of GPX5 needs to be assessed using a range of alternative substrates and electron donors. GPX5 is secreted by the epididymis and associates with the sperm plasma membrane. We showed that this transfer can occur via epididymosomes; however, the mechanism for transfer and the identity of a potential binding partner in the sperm membrane needs to be determined. Finally, our study utilized an in vitro system that needs to be translated to human sperm., Wider Implications of the Findings: Our study supports an important role for GPX5 as an antioxidant, possibly acting as a phospholipid hydroperoxidase and participating in the maintenance of cell and DNA integrity.
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- 2013
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7. Ignorance but not bliss: too little is known about the determinants of semen quality.
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Ford WC
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- Humans, Infertility, Male diagnosis, Infertility, Male etiology, Male, Oligospermia diagnosis, Oligospermia etiology, Risk Factors, Sperm Count methods, Sperm Count standards, Sperm Count statistics & numerical data, World Health Organization, Semen Analysis methods, Semen Analysis standards, Semen Analysis statistics & numerical data
- Published
- 2013
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8. Snapshots of a protein folding intermediate.
- Author
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Yamada S, Bouley Ford ND, Keller GE, Ford WC, Gray HB, and Winkler JR
- Subjects
- Bacterial Proteins genetics, Bacterial Proteins metabolism, Circular Dichroism, Crystallography, X-Ray, Cysteine chemistry, Cysteine genetics, Cysteine metabolism, Cytochrome c Group genetics, Cytochrome c Group metabolism, Heme metabolism, Kinetics, Models, Molecular, Molecular Structure, Mutation, Protein Denaturation, Protein Structure, Secondary, Protein Structure, Tertiary, Protein Unfolding, Spectrometry, Fluorescence, Thermus thermophilus genetics, Thermus thermophilus metabolism, Time Factors, Bacterial Proteins chemistry, Cytochrome c Group chemistry, Heme chemistry, Protein Folding
- Abstract
We have investigated the folding dynamics of Thermus thermophilus cytochrome c(552) by time-resolved fluorescence energy transfer between the heme and each of seven site-specific fluorescent probes. We have found both an equilibrium unfolding intermediate and a distinct refolding intermediate from kinetics studies. Depending on the protein region monitored, we observed either two-state or three-state denaturation transitions. The unfolding intermediate associated with three-state folding exhibited native contacts in β-sheet and C-terminal helix regions. We probed the formation of a refolding intermediate by time-resolved fluorescence energy transfer between residue 110 and the heme using a continuous flow mixer. The intermediate ensemble, a heterogeneous mixture of compact and extended polypeptides, forms in a millisecond, substantially slower than the ∼100-μs formation of a burst-phase intermediate in cytochrome c. The surprising finding is that, unlike for cytochrome c, there is an observable folding intermediate, but no microsecond burst phase in the folding kinetics of the structurally related thermostable protein.
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- 2013
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9. The effects of carbaryl on the development of zebrafish (Danio rerio) embryos.
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Schock EN, Ford WC, Midgley KJ, Fader JG, Giavasis MN, and McWhorter ML
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- Animals, Cell Death drug effects, Dose-Response Relationship, Drug, Embryo, Nonmammalian metabolism, Heart drug effects, Nervous System drug effects, Zebrafish metabolism, Carbaryl toxicity, Embryo, Nonmammalian drug effects, Insecticides toxicity, Water Pollutants, Chemical toxicity, Zebrafish embryology
- Abstract
In the United States, Sevin(™) brand insecticide is one of the most commonly used insecticides. The active ingredient in Sevin(™), carbaryl (1-napthyl-N-methylcarbamate), is a known acetylcholinesterase (AChE) inhibitor that prevents the breakdown of acetylcholine to acetate and choline at the synapse. While carbaryl successfully causes the death of insects by paralysis, it has also been shown to have negative effects on the development of several nontarget species. To study the effects of carbaryl on nontarget species, zebrafish (Danio rerio) were used, as they are a good model for both toxicology and development studies. Our study suggests that carbaryl induces changes in morphology, specifically in embryo size and shape. Additionally, carbaryl causes defects in heart formation that is characterized by a decrease in heart rate and a developmental delay/defect in cardiac looping. A significant decrease in the number of spinal cord neurons present was also observed. Further investigation showed that there was an increase in cell death in carbaryl-treated embryos. The results indicate that carbaryl may have a greater environmental impact than initially intended. Our study, which was conducted solely by undergraduates at a liberal arts college, indicates that carbaryl may be detrimental to the development of nontarget species.
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- 2012
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10. Comments on the release of the 5th edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen.
- Author
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Ford WC
- Subjects
- Humans, Infertility, Male diagnosis, Male, Models, Statistical, Predictive Value of Tests, Manuals as Topic, Semen Analysis, World Health Organization
- Abstract
The authors of the World Health Organization Semen Analysis Manual are to be congratulated on producing a new edition; it is an essential tool to disseminate good practice in andrology. However, the tests described have poor prognostic power to predict a man's fertility and show little about the underlying causes of sub-fertility. This commentary urges a revival of research into the diagnosis of male fertility. It suggests that fertility should be regarded as a continuum and that the artificial binary division between fertile and infertile should be abandoned. Models to predict a sub-fertile couple's chance of conception in a year should be developed on the basis of prospective data. These models would allow for sophisticated decision making about management. The future lies in the identification of tests to detect underlying pathologies open to specific treatment. Leads such as oxidative stress, defects in the intracellular regulation and the developing field of proteomics should be explored.
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- 2010
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11. Human spermatozoa contain multiple targets for protein S-nitrosylation: an alternative mechanism of the modulation of sperm function by nitric oxide?
- Author
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Lefièvre L, Chen Y, Conner SJ, Scott JL, Publicover SJ, Ford WC, and Barratt CL
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- Adaptor Proteins, Signal Transducing metabolism, Cysteine metabolism, Humans, Male, Mitochondrial Membrane Transport Proteins, Nitric Oxide Donors metabolism, Nitric Oxide Donors pharmacology, Nitric Oxide Synthase Type III metabolism, Proteome chemistry, S-Nitrosoglutathione metabolism, S-Nitrosoglutathione pharmacology, Seminal Vesicle Secretory Proteins metabolism, Tandem Mass Spectrometry, Voltage-Dependent Anion Channels metabolism, Nitric Oxide metabolism, Nitroso Compounds metabolism, Proteome metabolism, Proteomics methods, Spermatozoa metabolism
- Abstract
Nitric oxide (NO) enhances human sperm motility and capacitation associated with increased protein phosphorylation. NO activates soluble guanylyl cyclase, but can also modify protein function covalently via S-nitrosylation of cysteine. Remarkably, this mechanism remains unexplored in sperm although they depend on post-translational protein modification to achieve changes in function required for fertilisation. Our objective was to identify targets for S-nitrosylation in human sperm. Spermatozoa were incubated with NO donors and S-nitrosylated proteins were identified using the biotin switch assay and a proteomic approach using MS/MS. 240 S-nitrosylated proteins were detected in sperm incubated with S-nitroso-glutathione. Minimal levels were observed in glutathione or untreated samples. Proteins identified consistently based on multiple peptides included established targets for S-nitrosylation in other cells e.g. tubulin, GST and HSPs but also novel targets including A-kinase anchoring protein (AKAP) types 3 and 4, voltage-dependent anion-selective channel protein 3 and semenogelin 1 and 2. In situ localisation revealed S-nitrosylated targets on the postacrosomal region of the head and throughout the flagellum. Potential targets for S-nitrosylation in human sperm include physiologically significant proteins not previously reported in other cells. Their identification will provide novel insight into the mechanism of action of NO in spermatozoa.
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- 2007
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12. Counting sperm does not add up any more: time for a new equation?
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Lefièvre L, Bedu-Addo K, Conner SJ, Machado-Oliveira GS, Chen Y, Kirkman-Brown JC, Afnan MA, Publicover SJ, Ford WC, and Barratt CL
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- Calcium metabolism, Humans, Male, Proteomics, Sperm Capacitation physiology, Sperm Count, Spermatozoa cytology, Infertility, Male diagnosis, Spermatozoa physiology
- Abstract
Although sperm dysfunction is the single most common cause of infertility, we have poor methods of diagnosis and surprisingly no effective treatment (excluding assisted reproductive technology). In this review, we challenge the usefulness of a basic semen analysis and argue that a new paradigm is required immediately. We discuss the use of at-home screening to potentially improve the diagnosis of the male and to streamline the management of the sub-fertile couple. Additionally, we outline the recent progress in the field, for example, in proteomics, which will allow the development of new biomarkers of sperm function. This new knowledge will transform our understanding of the spermatozoon as a machine and is likely to lead to non-ART treatments for men with sperm dysfunction.
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- 2007
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13. Effects of assisted hatching method and age on implantation rates of IVF and ICSI.
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Ghobara TS, Cahill DJ, Ford WC, Collyer HM, Wilson PE, Al-Nuaim L, and Jenkins JM
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- Adult, Embryo, Mammalian surgery, Female, Humans, Microsurgery, Middle Aged, Zona Pellucida ultrastructure, Embryo Implantation, Fertilization in Vitro methods, Sperm Injections, Intracytoplasmic methods, Zona Pellucida physiology
- Abstract
The objective of this study was to investigate whether a change in assisted hatching (AH) technique from total to partial penetration of the zona pellucida improved the outcome of IVF and intracytoplasmic sperm injection cycles where AH was indicated. This was an observational study conducted from the beginning of January 2000 to the end of April 2005. Total AH was performed in 312 cycles, while partial AH was performed in 592 cycles. In women of all ages, implantation, clinical pregnancy and live birth rates were higher in the partial AH group than in the total AH group (12.6 versus 7.2%, P = 0.0001; 22.3 versus 15.7%, P = 0.02; 18.2 versus 12.5%, P = 0.03 respectively). The benefit of partial AH was most marked in women under 38 years old (i.e. the recurrent implantation failure group). The authors conclude that partial AH is associated with higher implantation and pregnancy rates than total AH, especially in women under 38 years old who suffer from recurrent implantation failure.
- Published
- 2006
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14. Glycolysis and sperm motility: does a spoonful of sugar help the flagellum go round?
- Author
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Ford WC
- Subjects
- Animals, Energy Transfer genetics, Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) genetics, Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) physiology, Humans, Male, Mice, Mice, Knockout, Adenosine Triphosphate metabolism, Glucose metabolism, Glycolysis genetics, Sperm Motility genetics, Sperm Tail enzymology
- Abstract
It is doubtful that diffusion can deliver sufficient ATP from the mitochondria to sustain activity at the distal end of the sperm flagellum. Glycolytic enzymes bound to the fibrous sheath could provide energy along the flagellum at the point it is required. An obligatory role for glycolysis is supported by the lack of progressive motility in sperm from mice where the gene for sperm-specific glyceraldehyde-3-phosphate dehydrogenase (GAPDHs) had been 'knocked out'. Here, I review some evidence against this idea. First, pure diffusion from the mitochondrion is likely to be adequate in species with smaller sperm, and it is possible that rapid ATP delivery required in larger sperm could be achieved by an adenylate kinase shuttle. Second, experience with alpha-chlorohydrin demonstrates that sperm can remain motile with normal ATP concentrations despite inhibition of GAPDHs; adverse effects only occur if glucose is added and high levels of glycolytic intermediates accumulate. These observations undermine the GAPDHs knockout mouse as evidence for an essential role of local glycolysis. Third, sperm from many species can remain motile for long periods in sugar-free media and excepting dog sperm, evidence that gluconeogenesis is a possible explanation, is weak. In most species, it is unlikely that local glycolysis is the only way that ATP can be supplied to the distal flagellum.
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- 2006
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15. Molecular mechanisms during sperm capacitation.
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Brewis IA, Moore HD, Fraser LR, Holt WV, Baldi E, Luconi M, Gadella BM, Ford WC, and Harrison RA
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- Acrosome Reaction, Adenosine, Animals, Calcitonin, Cell Membrane physiology, Fallopian Tubes, Female, Humans, Male, Pyrrolidonecarboxylic Acid analogs & derivatives, Signal Transduction, Spermatozoa ultrastructure, Thyrotropin-Releasing Hormone analogs & derivatives, Fertilization physiology, Sperm Capacitation physiology, Spermatozoa physiology
- Published
- 2005
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16. Relationship between reactive oxygen species production and lipid peroxidation in human sperm suspensions and their association with sperm function.
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Williams AC and Ford WC
- Subjects
- Fertilization in Vitro, Humans, Lipid Metabolism, Male, Oxidative Stress physiology, Sperm Motility, Acrosome Reaction physiology, Lipid Peroxidation physiology, Reactive Oxygen Species metabolism, Spermatozoa physiology
- Abstract
Objectives: To investigate if reactive oxygen species (ROS) production by human sperm suspensions could predict oxidative stress manifest as lipid peroxidation and if lipid peroxidation was a useful predictor of human sperm function., Design: Laboratory study., Setting: Research laboratory associated with reproductive medicine clinic., Patient(s): Eighty-three couples under evaluation for IVF donated the surplus from a diagnostic semen sample., Intervention(s): Cells were separated from seminal plasma on a 30% Percoll gradient., Main Outcome Measure(s): Reactive oxygen species production, lipid peroxidation, sperm motility measured by computer-assisted semen analysis and ability of the sperm to acrosome react., Result(s): Forty-four samples exhibited ROS production < or =20 000 relative light units (rlu)/s/10(8) sperm and lipid peroxidation < or =40 nmol malondialdehyde/10(8) sperm. The remainder fell into two distinct groups; both exhibited a linear relationship between lipid peroxidation and ROS production but of markedly differing slopes. Abstinence time had no effect. Lipid peroxidation was a good predictor of sperm motility and their ability to acrosome react., Conclusion(s): Reactive oxygen species production in sperm suspensions is an index of overall oxidative stress experienced by sperm, but sperm divide into two classes of ability to resist oxidative stress. Lipid peroxidation should be investigated as a clinical test of sperm function.
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- 2005
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17. Functional significance of the pentose phosphate pathway and glutathione reductase in the antioxidant defenses of human sperm.
- Author
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Williams AC and Ford WC
- Subjects
- Antioxidants physiology, Cells, Cultured, Humans, Lipid Peroxidation physiology, Male, Glutathione Peroxidase metabolism, Glutathione Reductase metabolism, Pentose Phosphate Pathway physiology, Reactive Oxygen Species metabolism, Spermatozoa enzymology
- Abstract
Glutathione peroxidase is one of the principal antioxidant defense enzymes in human spermatozoa, but it requires oxidized glutathione to be reduced by glutathione reductase using NADPH generated in the pentose phosphate pathway. We investigated whether flux through the pentose phosphate pathway would increase in response to oxidative stress and whether glutathione reductase was required to protect sperm from oxidative damage. Isotopic measurements of the pentose phosphate pathway and glycolytic flux, thiobarbituric acid assay of malondialdehyde for lipid peroxidation, and computer-assisted sperm analysis for sperm motility were assessed in a group of normal, healthy semen donors. Applying moderate oxidative stress to human spermatozoa by adding cumene hydroperoxide, H(2)O(2), or xanthine plus xanthine oxidase or by promoting lipid peroxidation with ascorbate increased flux through the pentose phosphate pathway without changing the glycolytic rate. However, adding higher concentrations of oxidants inhibited both the pentose phosphate pathway and glycolytic flux. At concentrations of 50 microg/ml or greater, the glutathione reductase-inhibitor 1,3-bis-(2-chloroethyl) 1-nitrosourea decreased flux through the pentose phosphate pathway and blocked the response to cumene hydroperoxide. It also increased lipid peroxidation and impaired the survival of motility in sperm incubated under 95% O(2). These data show that the pentose phosphate pathway in human spermatozoa can respond dynamically to oxidative stress and that inhibiting glutathione reductase impairs the ability of sperm to resist lipid peroxidation. We conclude that the glutathione peroxidase-glutathione reductase-pentose phosphate pathway system is functional and provides an effective antioxidant defense in normal human spermatozoa.
- Published
- 2004
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18. Regulation of sperm function by reactive oxygen species.
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Ford WC
- Subjects
- Animals, Humans, Male, Reactive Oxygen Species metabolism, Sperm Capacitation physiology, Spermatozoa metabolism
- Abstract
Sperm capacitation can be increased by the addition of reactive oxygen species (ROS) and decreased by antioxidants. Broadly consistent results have been achieved with a wide variety of methods and across different species. Exposure to ROS increases protein tyrosine phosphorylation consequent on an increase in cAMP and activation of tyrosine kinase and inhibition of tyrosine phosphatase. The measurement of ROS production by sperm is complicated by contamination of suspensions by leukocytes, laying many studies open to doubt. In human sperm the observation that extracellular NADPH could support superoxide production detected with the chemiluminescent probe lucigenin and had physiological effects similar to hydrogen peroxide led to the suggestion that they contained NADPH oxidase activity to generate ROS to support capacitation. However, the realization that lucigenin can signal superoxide artefactually, combined with failure to detect superoxide production using spin trapping techniques or to detect NADPH oxidase components in mature sperm, and confirmation of old reports that NADPH solution contains substantial amounts of hydrogen peroxide due to autoxidation, have undermined this hypothesis. Although the presence of significant NADPH oxidase activity in mature human sperm now seems less likely, other observations continue to suggest that they can make ROS in some way. There is stronger evidence that animal sperm can make ROS although these may be mainly of mitochondrial origin.
- Published
- 2004
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19. Defining poor ovarian response during IVF cycles, in women aged <40 years, and its relationship with treatment outcome.
- Author
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Kailasam C, Keay SD, Wilson P, Ford WC, and Jenkins JM
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- Adult, Dose-Response Relationship, Drug, Female, Follicle Stimulating Hormone administration & dosage, Follicle Stimulating Hormone therapeutic use, Humans, Oocytes, Ovary drug effects, Pregnancy, Pregnancy Rate, Retrospective Studies, Tissue and Organ Harvesting, Treatment Outcome, Aging, Fertilization in Vitro, Ovary physiology
- Abstract
Background: Poor ovarian response limits IVF success but assessing interventions is difficult because of the wide variation in definition. This study attempts to derive objective definitions of poor response., Methods: A retrospective study of a consecutive series of 1190 patients aged <40 years undergoing their first IVF/ICSI cycle was undertaken. Factors adversely affecting implantation, including advanced female age, were excluded. Clinical outcome in cycles reaching oocyte retrieval (n = 1036) were evaluated with respect to gonadotrophin dose used and oocyte number. Cancelled cycles (n = 154) were analysed in relation to the stimulation dose at cancellation and outcome of their subsequent cycle., Results: Cycle cancellation for patients on >/=300 IU FSH/day compared to those on a lower dose was associated with a significantly worse outcome in the subsequent cycle. If <3000 IU FSH/cycle were administered, clinical pregnancy rates remained favourable if <4 eggs were recovered (29 versus 33% for >/=5 eggs). By contrast, if >/=3000 IU FSH was required, the pregnancy rate was 25% if >/=5 eggs were recovered but declined to 7% if <4 were obtained., Conclusions: Definitions of poor response should include the degree of ovarian stimulation used. A low oocyte number is only detrimental if the cumulative dose is >3000 IU FSH. Cancellation at >/=300 IU FSH/day is associated with a significantly worse prognosis and could define poor response.
- Published
- 2004
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20. Effects of Ca-ATPase inhibitors on the intracellular calcium activity and motility of human spermatozoa.
- Author
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Williams KM and Ford WC
- Subjects
- Acrosome Reaction drug effects, Cell Survival drug effects, Endoplasmic Reticulum metabolism, Humans, Male, Osmolar Concentration, Quercetin pharmacology, Sarcoplasmic Reticulum metabolism, Spermatozoa metabolism, Thapsigargin pharmacology, Calcium metabolism, Calcium-Transporting ATPases antagonists & inhibitors, Enzyme Inhibitors pharmacology, Intracellular Membranes metabolism, Sperm Motility drug effects, Spermatozoa physiology
- Abstract
Although evidence suggests that high intracellular calcium activity ([Ca2+]i) inhibits sperm motility, data concerning [Ca2+]i within, or slightly above, the physiological range are sparse, particularly in mammalian sperm. We investigated inhibitors of the sarcoplasmic/endoplasmic reticulum Ca-ATPase (SERCA) and the plasma membrane Ca-ATPase with the objective of increasing the intracellular calcium ion activity in human spermatozoa to study its effect on motility and other functions. Thapsigargin (20 micromol/L) increased [Ca2+]i from 140 +/- 7 nmol/L over an approximately 2-min period to reach a plateau of 530 +/- 84 nmol/L (mean +/- SEM, n = 3, p < 0.05). In sperm suspended in calcium-free medium thapsigargin increased [Ca2+]i from 13 +/- 3.3 to 35 +/- 7.5 nmol/L (p < 0.01), consistent with the release of calcium from intracellular stores. Cyclopiazonic acid (60 micromol/L) caused a transient decrease in [Ca2+]i. Quercetin, (200 micromol/L) caused a rapid increase in [Ca2+]i to 1280 +/- 90 nmol/L, after which [Ca2+]i fell quickly at first but then more slowly. Thapsigargin (20 micromol/L) caused approximately 70% of sperm to acrosome react in < or = 5 min, but once acrosome reacted, many sperm died over the next 30 min. Lower concentrations of thapsigargin caused fewer acrosome reactions but were less toxic. Both thapsigargin and quercetin caused rapid dose-dependent decreases in sperm motility. The results are consistent with high [Ca2+]i in the range observed in caput epididymal or cryopreserved spermatozoa inhibiting motility, but might be confounded by other events following the acrosome reaction.
- Published
- 2003
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21. Tubal damage in infertile women: prediction using chlamydia serology.
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Akande VA, Hunt LP, Cahill DJ, Caul EO, Ford WC, and Jenkins JM
- Subjects
- Adult, Aging, Antibodies, Fungal blood, Chlamydia Infections immunology, Fallopian Tube Diseases diagnosis, Fallopian Tube Diseases physiopathology, Female, Fluorescent Antibody Technique methods, Humans, Laparoscopy, Likelihood Functions, Middle Aged, Prognosis, Severity of Illness Index, Chlamydia Infections complications, Chlamydia Infections diagnosis, Fallopian Tube Diseases complications, Fallopian Tube Diseases microbiology, Infertility, Female etiology, Serologic Tests
- Abstract
Background: The study explores the relationship between serum chlamydia antibody titres (CATs) and detection of tubal damage in infertile women., Methods: The tubal status and pelvic findings in 1006 women undergoing laparoscopy for infertility were related to CAT, which was measured using the whole-cell inclusion immunofluorescence test., Results: A negative correlation between CAT and age was noted. A linear trend between serum CAT and the likelihood of tubal damage, including severe damage, was observed (P < 0.001). Titres in women with tubal damage (median 1:1024; range <1:64-1:4096) were significantly (P < 0.001) higher than in women with endometriosis alone (median <1:64; range <1:64-1:512) or those with a normal pelvis (median <1:64; range <1:64-1:1024). Women with positive titres were more likely to have pelvic adhesions than tubal occlusion unless titres were very high, when tubal damage was likely to be more severe., Conclusions: CATs are of predictive value in the detection of tubal damage and are quantitatively related to the severity of damage. For practical clinical purposes, Chlamydia serology is useful mainly as a screening test for the likelihood of tubal damage in infertile women and may facilitate decisions on which women should proceed with further investigations without delay.
- Published
- 2003
- Full Text
- View/download PDF
22. Reactive oxygen species generation by human spermatozoa.
- Author
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Ford WC
- Subjects
- Humans, Male, Reactive Oxygen Species metabolism, Spermatozoa metabolism
- Published
- 2003
- Full Text
- View/download PDF
23. Prolonged use of oral contraception before a planned pregnancy is associated with a decreased risk of delayed conception.
- Author
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Farrow A, Hull MG, Northstone K, Taylor H, Ford WC, and Golding J
- Subjects
- Adult, Age Factors, Alcohol Drinking, Body Mass Index, Educational Status, Female, Gestational Age, Humans, Logistic Models, Odds Ratio, Parity, Pregnancy, Prospective Studies, Smoking, Surveys and Questionnaires, Time Factors, Contraceptives, Oral administration & dosage, Fertilization
- Abstract
Background: The aim of this study was to investigate the association of total duration of oral contraceptive usage with time to conception., Methods: This was a prospective study of 8497 planned pregnancies drawn from a population that recruited 85% of eligible couples in South-West England who were expecting a baby in a 21 month period. Self-completion questionnaires were administered at 18 weeks gestation to ascertain parity, paternity, co-habitation, use of the contraceptive pill, smoking and alcohol status, educational achievement, height, weight and time taken to conceive. Logistic regression was used to identify factors independently related to conception in < or =12 months., Results: Of the participants, 74% conceived in < or =6 months, 14% in 6-12 months and 12% after 1 year. Previous prolonged oral contraceptive usage was statistically significantly associated with a decreased risk of delayed conception. Prolonged use of oral contraception was also associated with improved fecundity independent of other factors. Selection bias due to particularly fertile women using oral contraceptives is unlikely because similar odds ratios were calculated for nulligravid women., Conclusions: Women who have prolonged use of oral contraceptives might be reassured that they will not be disadvantaged in terms of time taken to achieve conception.
- Published
- 2002
- Full Text
- View/download PDF
24. Male employment in some printing trades is associated with prolonged time to conception.
- Author
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Ford WC, Northstone K, and Farrow A
- Subjects
- Animals, Female, Male, Pregnancy, Pregnancy Rate, Employment, Fertilization, Occupational Exposure
- Abstract
We investigated whether male employment in defined occupational groups was associated with decreased fecundity as revealed by prolonged time to conception. The analysis was carried out on data from questionnaires completed over a period of 21 months by 4808 couples with a planned pregnancy and collected as part of the Avon Longitudinal Study of Pregnancy and Childhood. Previously logistic regression had identified nine non-occupational factors associated with taking >6 or >12 months to conceive and this model was used to analyse the association of the fathers ever having worked in defined occupational groups with delayed conception. If the man had worked in 'Printing and related trades' (OPCS code 56), couples had a statistically significantly increased odds ratio (OR) of taking >6 [1.86 (1.21, 2.94)] or >12 months [1.96 (1.13, 3.39)] to conceive [OR (95% confidence intervals)] after adjustment for non-occupational factors. The association with time to conception was stronger in the subgroup 'Other printing related trades' (OPCS code 569) but no statistically significant associations after adjustment for other factors were found for other printing jobs.
- Published
- 2002
- Full Text
- View/download PDF
25. Predicting conception.
- Author
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Glazener CM and Ford WC
- Subjects
- Female, Fertilization in Vitro statistics & numerical data, Humans, Infertility, Female, Infertility, Male, Male, Pregnancy, Pregnancy Outcome, Fertilization physiology, Fertilization in Vitro methods
- Abstract
Infertility is relative. Research into effective treatment must focus on couples with single, identifiable causes for their infertility, and must take into account the effect of chance and time on eventual success. Women with ovulatory infertility, who have no other subfertility factors, can expect normal conception rates when ovulation is restored. Unfortunately, there is no similar simple treatment for male infertility, although complicated and expensive treatment may help. Selection of the couples most likely to benefit from such help will result in the most cost-effective use of scarce resources. Knowledge of duration of infertility and the postcoital test result can help to identify those couples who have a reasonable chance of conception without treatment and those who have virtually no chance without it.
- Published
- 2002
- Full Text
- View/download PDF
26. Male infertility: tales of progress and frustration.
- Author
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Ford WC
- Subjects
- Diagnostic Techniques, Endocrine, Humans, Infertility, Male diagnosis, Infertility, Male physiopathology, Male, Sperm Injections, Intracytoplasmic, Infertility, Male therapy
- Abstract
This article describes andrology research, inspired by Professor Michael Hull, to develop sperm function tests and to understand the basic causes of male infertility. No generally acceptable sperm function test has yet been devised. Computer-assisted semen analysis (CASA) proved of limited value in predicting the outcome of in vitro fertilization (IVF) although it was more useful in donor insemination. High intracellular Ca2+ activity, [Ca2+]i, is involved in decreasing motility in cryopreserved sperm. Capacitative calcium entry after depletion of intracellular stores may generate the sustained increase in [Ca2+]i that initiates the acrosome reaction. Our data support the presence of Ca2+ stores as thapsigargin increased [Ca2+]i in sperm in Ca2+ -free medium. Recent observations indicate that cAMP enhances capacitative calcium entry, acting upstream of emptying of the store. Excess reactive oxygen species (ROS) is an important cause of sperm pathology but at low concentrations ROS regulate capacitation. Our evidence shows that ROS are produced by leucocytes present in sperm suspensions. We have been unable to demonstrate that human sperm produce ROS. The relationship between ROS production and lipid peroxidation indicates that sperm from some men are resistant to lipid peroxidation, possibly because of better antioxidant defences. We conclude that the future of andrology lies in the identification of the basic causes of infertility and not in more detailed descriptions of the properties of semen.
- Published
- 2002
- Full Text
- View/download PDF
27. The motility of demembranated human spermatozoa is inhibited by free calcium ion activities of 500 nmol/L or more.
- Author
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Williams KM and Ford WC
- Subjects
- Adult, Cell Membrane, Cryopreservation, Dose-Response Relationship, Drug, Humans, Male, Octoxynol, Semen Preservation, Sperm Motility drug effects, Spermatozoa drug effects, Spermatozoa metabolism, Calcium metabolism, Sperm Motility physiology, Spermatozoa physiology
- Abstract
A number of studies have demonstrated that high calcium ion activities inhibit sperm motility, but little is known about the effect of different calcium activities close to the physiological range. Therefore, we investigated whether raising calcium activities within the submicromolar range would inhibit the motility of demembranated human spermatozoa. Spermatozoa were demembranated with Triton X-100 and motility was measured objectively by computer assisted semen analysis. Motility, reactivated by 1 mol adenosine 5'-triphosphate (AlphaTauP)/L, was short lived, with maximum activity only sustained for about 1 min. Reactivated motility was not affected by 50 micromol cAMP/L. The amplitude of lateral head displacement was significantly greater at room temperature than at 37 degrees C, but there were no significant differences between the percentage of sperm motile or their velocity at the two temperatures. The calcium buffer 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) at 1 mmol/L was included in the demembranation-reactivation medium, and free calcium ion activities were calibrated using the fluorescent calcium probe Fura-2. Calcium ion activities of > or =500 nmol/L significantly inhibited the percentage of demembranated-reactivated spermatozoa that were motile, and the velocity and lateral head displacement of these cells. The range of intracellular calcium activities in spermatozoa from 24 cryopreserved ejaculates was 110-534 nmol/L; roughly twice the value in fresh spermatozoa. Therefore, calcium ion activities in the range observed in cryopreserved spermatozoa can inhibit the activity of demembranated human spermatozoa.
- Published
- 2001
- Full Text
- View/download PDF
28. The role of glucose in supporting motility and capacitation in human spermatozoa.
- Author
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Williams AC and Ford WC
- Subjects
- Acrosome Reaction drug effects, Adenosine Triphosphate metabolism, Animals, Antimetabolites pharmacology, Calcimycin pharmacology, Cricetinae, Deoxyglucose pharmacology, Enzyme Inhibitors pharmacology, Fructose pharmacology, Galactose pharmacology, Glycolysis physiology, Humans, Ionophores pharmacology, Male, Mannose pharmacology, Pentoxifylline pharmacology, Progesterone pharmacology, Sperm-Ovum Interactions drug effects, Spermatozoa drug effects, Glucose pharmacology, Sperm Capacitation drug effects, Sperm Motility drug effects, Spermatozoa metabolism
- Abstract
Glucose has been reported to be beneficial to human sperm for optimal capacitation and fertilization, although it is unclear whether glucose is required for providing extra metabolic energy through glycolysis, or for generating some other metabolic product. In this study, the effects of sugars on human sperm capacitation, motility, and energy production were investigated. The glucose concentration that supported the greatest number of acrosome reactions was 5.56 mmol L(-1). Compared with incubations with no added sugar, this concentration of glucose, fructose, mannose, or galactose appeared to slightly increase the number of acrosome reactions occurring after 18 hours of capacitation, or following induction by 2 micromol A23187 + 3.6 mmol pentoxifylline L 1, but only glucose had a statistically significant effect. Glucose supported increased penetration of zona-free hamster oocytes, but its advantage was not statistically significant. The addition of 5.56 mmol glucose or fructose L(-1) to sugar-free medium immediately increased the adenosine triphosphate (ATP) concentration and motility of sperm. These parameters were then stable for 3 hours, but declined markedly after 18 hours. In the absence of a glycolysable sugar, motility began to decline in the first hour and only 2% or 3% of sperm remained motile after 18 hours. Glucose or fructose was required to support hyperactivated motility. 2-Deoxyglucose was detrimental to the ATP concentration and motility of sperm, and supported fewer spontaneous or progesterone-stimulated acrosome reactions than were observed in the absence of a sugar. We conclude that glycolytic ATP production is required for vigorous motility and hyperactivation in human sperm. Other products of glucose metabolism are not essential to support capacitation, but they may have a small, enhancing effect.
- Published
- 2001
29. Biological mechanisms of male infertility.
- Author
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Ford WC
- Subjects
- Humans, Infertility, Male genetics, Infertility, Male therapy, Male, Reactive Oxygen Species, Sperm Injections, Intracytoplasmic economics, Infertility, Male etiology
- Published
- 2001
- Full Text
- View/download PDF
30. Value of the hamster oocyte test and computerised measurements of sperm motility in predicting if four or more viable embryos will be obtained in an IVF cycle.
- Author
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Ford WC, Williams KM, Harrison S, Rees JM, Ray BD, McLaughlin EA, and Hull MG
- Subjects
- Adult, Animals, Cricetinae, Female, Humans, Logistic Models, Male, Middle Aged, Predictive Value of Tests, Pregnancy, Sperm-Ovum Interactions, Computer Simulation, Fertilization in Vitro, Likelihood Functions, Models, Statistical, Oocytes physiology, Sperm Motility physiology
- Abstract
The experimental group consisted of men from 81 couples waiting for in vitro fertilization (IVF), about half of whom had sperm dysfunction defined by a negative post-coital test. A diagnostic semen sample was subjected to a hamster oocyte penetration test (HOPT) after stimulation of the acrosome reaction with A23187 +/- pentoxifylline and to computerized sperm motility measurements (CASA) as well as conventional semen analysis according to the WHO protocol. Logistic regression was used to identify parameters that predicted the probability of achieving four or more viable embryos at IVF among the 65 couples from whom four or more oocytes were collected. The number of oocytes available and whether the woman had previously been pregnant (ever pregnant) were important factors but once these had been taken into account a number of sperm parameters had additional predictive power. The most useful of these were the percentage sperm static (CASA) or the percent sperm progressively motile (conventional semen analysis) in the Percoll preparation. A model incorporating the number of oocytes collected, ever pregnant and percentage sperm static achieved 85% correct prediction of outcome in the experimental dataset but only 62% correct prediction in an independent set of 280 IVF cycles. The percentage of hamster oocytes penetrated was a significant predictor but had no advantage over simple motility measurements. The results illustrate the difficulty of basing a prognosis for achieving satisfactory fertilization in IVF on the properties of spermatozoa.
- Published
- 2001
- Full Text
- View/download PDF
31. A critical investigation of NADPH oxidase activity in human spermatozoa.
- Author
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Richer SC and Ford WC
- Subjects
- Acridines, Cytochrome b Group analysis, Cytochrome c Group metabolism, Electron Spin Resonance Spectroscopy, Humans, Hydrogen Peroxide metabolism, Luminescent Measurements, Male, NADP metabolism, NADP pharmacology, Oxidation-Reduction, Spectrophotometry methods, Spermatozoa drug effects, Superoxides metabolism, NADPH Oxidases metabolism, Spermatozoa enzymology
- Abstract
It has been suggested that human spermatozoa contain an NADPH oxidase that could generate reactive oxygen species involved in signalling pathways to promote fertility. The proposal depends on observations that the addition of NADPH to purified human spermatozoa stimulates chemiluminescence by the superoxide (O2-) probe, lucigenin. We confirmed these observations, but demonstrated that lucigenin increases NADPH consumption by spermatozoa and stimulates artefactual O2- production via a diphenyleneiodonium (DPI) sensitive flavoprotein. In the absence of cytochrome c, DPI-inhibitable NADPH oxidation by permeabilized spermatozoa was 8 times too small to account for the rate of NADPH-stimulated cytochrome c reduction. Thus NADPH can directly reduce cytochrome c by a flavoprotein dependent mechanism making this O2- assay also unreliable in sperm suspensions. We were unable to observe O2- production by 40 x 10(6) spermatozoa/ml using electron paramagnetic resonance spectroscopy but could identify O(2)(-) generation from 2000 4beta-phorbol-12-myristate-13-actetate (PMA)-stimulated leukocytes. Using spectrophotometry, we did not detect the reduced cytochrome b(558) component of the neutrophil NADPH oxidase in human spermatozoa. No hydrogen peroxide generation was observed using a sensitive Amplex Red assay. We conclude that human spermatozoa do not possess significant NADPH oxidase activity and that the mechanism by which NADPH promotes capacitation must be re-evaluated.
- Published
- 2001
- Full Text
- View/download PDF
32. Delayed conception and active and passive smoking. The Avon Longitudinal Study of Pregnancy and Childhood Study Team.
- Author
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Hull MG, North K, Taylor H, Farrow A, and Ford WC
- Subjects
- Adult, Body Weight, Female, Gestational Age, Humans, Longitudinal Studies, Male, Pregnancy, Surveys and Questionnaires, Time Factors, Fertilization, Infertility etiology, Smoking adverse effects, Tobacco Smoke Pollution adverse effects
- Abstract
Objective: To determine whether passive as well as active smoking by women or smoking by men is associated with delayed conception, after adjustment for confounding factors., Design: Population study of couples expecting a baby. Logistic regression was performed to identify factors associated with delayed conception., Setting: The Avon Health Authority area, United Kingdom., Patient(s): All couples expected to deliver between April 1991 and December 1992., Intervention(s): Questionnaires administered early in pregnancy., Main Outcome Measure(s): Time taken to conceive, categorized as <6 months, 6-11 months, 1-3 years, and >3 years., Result(s): After correction for confounding factors, delayed conception was statistically significantly associated with both active smoking by the woman (odds ratio [OR] 1.23 [95% CI 0.98-1.49] for > 6 months and 1.54 [95% CI 1.19-2.01] for >12 months) and her exposure to passive smoking (OR 1.17 [95% CI 1.02-1.37] and 1.14 [95% CI 0.92-1.42]) compared with women with no exposure to tobacco smoke (referent). Heavy smoking by men was independently associated with delayed conception. In active smokers, the effect increased with the number of cigarettes., Conclusion(s): Smoking by men and passive and active smoking by women are associated with delayed conception.
- Published
- 2000
- Full Text
- View/download PDF
33. The prognostic power of the post-coital test for natural conception depends on duration of infertility.
- Author
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Glazener CM, Ford WC, and Hull MG
- Subjects
- Adult, Female, Humans, Male, Prognosis, Proportional Hazards Models, Sperm Count, Sperm Motility, Spermatozoa abnormalities, Time Factors, Coitus, Fertilization, Infertility, Semen physiology, Spermatozoa physiology
- Abstract
Controversy about the value of the post-coital test (PCT) has prompted us to re-analyse data from 207 couples, originally studied between 1982 and 1983, with at least 12 months' infertility at presentation, complete diagnostic information and exclusion of female factors, to clarify the effect of duration of infertility on the prediction of conception. In couples with less than 3 years infertility and a positive PCT, 68% conceived within 2 years compared with 17% of those with a negative result. After 3 years, corresponding rates were 14% and 11%. The relative risks of conception [95% confidence interval (CI)] calculated using the Cox's proportional hazards model were 0.23 (0.12-0.43) for a negative PCT (reference positive PCT) and 0.25 (0.13-0.51) for more than 36 months infertility (reference 12-23 months). Semen analysis had no extra predictive power given the duration of infertility and the PCT. The PCT is an effective predictor of conception where defined female causes of infertility are absent and duration of infertility is less than 3 years. Once infertility is prolonged (beyond 3 years) the conception rate is low even with a positive test because a large proportion of couples remaining childless so long have true unexplained infertility. Use of the PCT will enable clinicians to allocate scarce, expensive and invasive resources effectively.
- Published
- 2000
- Full Text
- View/download PDF
34. Increasing paternal age is associated with delayed conception in a large population of fertile couples: evidence for declining fecundity in older men. The ALSPAC Study Team (Avon Longitudinal Study of Pregnancy and Childhood).
- Author
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Ford WC, North K, Taylor H, Farrow A, Hull MG, and Golding J
- Subjects
- Adult, Contraceptive Agents, Female therapeutic use, Female, Fertilization, Humans, Male, Maternal Age, Population Surveillance, Pregnancy, Smoking, Social Class, Time Factors, United Kingdom epidemiology, Aging physiology, Fertility physiology
- Abstract
The impact of male age on fecundity remains controversial. Here, a large population study was used to investigate the effect of paternal age on time to conception. All couples in the Avon Health district expecting a baby between 1 April 1991 and 31 December 1992 were eligible. Questionnaires completed by both the man and the woman at 18 weeks gestation covered specific fertility factors, e.g. parity, paternity, cohabitation and oral contraception; and non-specific factors, e.g. educational achievement, housing, cigarette smoking, alcohol consumption, obesity. Logistic regression was used to identify factors independently related to conception in < or =6 or < or =12 months. Of 8515 planned pregnancies, 74% were conceived in < or =6 months, 14% in the second 6 months and 12% after more than a year. Nine variables, including the age of the woman, were independently related to time to conception. After adjustment for these, the likelihood of conception within 6 or 12 months was lower in older men. Compared to men <25 years old, the adjusted odds ratios (95% confidence interval) for conception in < or =12 months were 0.62 (0.40, 0.98), 0.50 (0.31, 0.81) and 0.51 (0.31, 0.86) in men aged 30-34, 35-39 and > or =40 years respectively.
- Published
- 2000
- Full Text
- View/download PDF
35. Gender reassignment and assisted reproduction: An ethical analysis. Bristol Centre for Reproductive Medicine Ethics Advisory Committee.
- Author
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Brothers D and Ford WC
- Subjects
- Adolescent, Adult, Child, Child Development, Child, Preschool, Female, Humans, Parenting, Patient Selection, Ethics, Medical, Gender Identity, Reproductive Techniques, Transsexualism psychology, Transsexualism surgery
- Published
- 2000
- Full Text
- View/download PDF
36. Sucralose: lack of effects on sperm glycolysis and reproduction in the rat.
- Author
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Kille JW, Ford WC, McAnulty P, Tesh JM, Ross FW, and Willoughby CR
- Subjects
- Adenosine Triphosphate analysis, Animals, Animals, Newborn, Body Weight drug effects, Carbon Dioxide metabolism, Drinking drug effects, Eating drug effects, Female, Fluorometry, Glycolysis drug effects, Glycolysis physiology, Litter Size drug effects, Male, Random Allocation, Rats, Rats, Sprague-Dawley, Reproduction drug effects, Scintillation Counting, Single-Blind Method, Spermatozoa drug effects, Sucrose toxicity, Glucose metabolism, Reproduction physiology, Spermatozoa metabolism, Sucrose analogs & derivatives, Sweetening Agents toxicity
- Abstract
Certain chlorine-substituted sugars with chemical similarities to sucralose have been demonstrated previously to diminish or inhibit sperm glycolysis and fertility in the rat ([Ford]). In order to investigate this potential for sucralose, epididymal spermatozoa were recovered from rats exposed in vivo to oral doses of one of three of these substituted sugars: 6-chloroglucose (6-CG, 24mg/kg/day, positive control), sucralose (500mg/kg/day, over 300 times the expected human daily intake), or a 6'-substituted isomer of sucralose, trichloro de-oxy sucrose (TCDS, 100mg/kg/day, a potential trace impurity in commercial sucralose); distilled water served as the negative control. After incubation of the spermatozoa with D-[U-(14)C] glucose, measurements of (14)CO(2) and of ATP content showed no impairment of the glycolytic ability of spermatozoa in any of the groups except for a marked inhibition for those exposed to 6-CG, the positive control. In order to determine whether other parameters of reproduction and fertility could be affected, reproductive endpoints were examined following oral exposure of male and female rats to sucralose. Sucralose was fed in the diet at concentrations of 0, 0.3, 1.0 and 3.0% (approx. 100, 365 and 1150 times the EDI) to groups of 30 male and 30 female rats for 10 weeks prior to mating, and continued through two subsequent generations until weaning of the F(2) pups. Two litters were produced per generation. Food consumption and weight gain in the F(0) and F(1) generations were depressed in all sucralose groups before mating and in all four litters prior to weaning. The decrease in initial average weight for newborn pups probably reflects the increased litter sizes noted for sucralose-treated groups and the reduced food consumption of the dams during gestation and lactation. The latter is a result primarily of the unpalatability of sucralose to rats ([McNeil,]). Caecal enlargement (a common animal response to large doses of indigestible material) occurred in both the F(0) and F(1) parents. Increased kidney weights, possibly associated with increased water intake, were observed primarily among animals receiving 3% sucralose (no renal histopathology has been detected). Decreased thymus weights occurred in F(1) males and in both F(1) and F(2) females at the 3% level. Subsequent studies specifically designed to investigate the potential for adverse immune system effects of sucralose ([McNeil,]) showed no adverse effects. These findings are consistent with investigations by others showing that decreases in thymus weights occur in young rats in response to stressful conditions associated with reductions in weight gain. All reproductive indices (oestrous cycles, mating behaviour, fertility, gestation, maternal and foetal viability, foetal development, parturition, pup maturation and lactation) were comparable between the control and sucralose-treated groups. We conclude from these results that sucralose has no effect on sperm glycolysis or on male or female reproductive performance in the rat.
- Published
- 2000
- Full Text
- View/download PDF
37. Reactive oxygen species (ROS) production and the outcome of diagnostic tests of sperm function.
- Author
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Whittington K, Harrison SC, Williams KM, Day JL, McLaughlin EA, Hull MG, and Ford WC
- Subjects
- Adult, Autoantibodies analysis, Autoantibodies immunology, Cell Survival, Cervix Mucus physiology, Cervix Uteri physiology, Female, Humans, Infertility, Male metabolism, Male, Reference Values, Sperm Motility, Spermatozoa immunology, Spermatozoa metabolism, Reactive Oxygen Species metabolism, Spermatozoa physiology
- Abstract
Washed sperm suspensions from 64 out of 89 (72%) randomly selected infertility patients produced detectable reactive oxygen species (ROS) compared to 17 out of 67 (25%) prospective semen donors (p < 0.01, Chi-square test). Among patients, the median sperm concentration in ejaculates which yielded sperm suspensions that generated detectable levels of ROS was lower than in those which did not: 36.2 (15.63-57.64) vs. 71.5 (22-108) x 10(6)/mL, respectively (median (interquartile range), p < 0.05, Kruskal-Wallis test). In samples that produced ROS, the basal rate of production and the rates after stimulation with 50 mumol N-formyl met leu phe (N-FMLP) l-1 or with 100 nmol phorbol 12-myristate 13-acetate (PMA) l-1 were significantly and inversely correlated with sperm concentration in the ejaculate (r = -0.43, -0.41 and -0.35, respectively, p < 0.01 Spearman's rank correlation). The rate of ROS production showed no relationship to the motility of spermatozoa in semen, whether evaluated visually or via computer assisted semen analysis. However, there was a significant negative correlation (r = -0.370) between the motile, normal sperm concentration (MNSC) and basal ROS production, and when stimulated with N-FMLP (r = -0.311) or with PMA (r = -0.249) (all p < 0.05). In patient samples that generated detectable ROS, the ability of the spermatozoa to retain motility for 24 h after preparation on a 40/80% Percoll gradient was negatively correlated with basal ROS production (r = -0.310, p < 0.05). ROS production was also related to the outcome of in vitro sperm mucus penetration tests. Unstimulated levels of ROS production showed a significant (p < 0.05), negative correlation with the number of progressively motile spermatozoa present in mucus after 15 (r = -0.379) and 60 (r = -0.362) min. These results suggest that sperm samples with increased ROS tend to have poor semen quality and reduced performance in a number of routine, diagnostic sperm function tests.
- Published
- 1999
- Full Text
- View/download PDF
38. Relative contribution of leukocytes and of spermatozoa to reactive oxygen species production in human sperm suspensions.
- Author
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Whittington K and Ford WC
- Subjects
- Humans, In Vitro Techniques, Infertility, Male metabolism, Male, Semen cytology, Semen metabolism, Leukocytes metabolism, Reactive Oxygen Species metabolism, Spermatozoa metabolism
- Abstract
The contribution of leukocytes and of spermatozoa to reactive oxygen species (ROS) production in prepared sperm suspensions from donors and subfertility patients was compared. In both groups, more leukocytes/10(6) spermatozoa were counted in samples which produced detectable ROS than in those that did not: Donors-645 vs. 170 (medians, n = 7; p < 0.01, Kruskal-Wallis), Subfertile group-1785 (n = 18) vs. 11 (n = 8) (p < 0.005, Kruskal-Wallis), respectively. Leukocyte concentrations were correlated with basal (r = 0.826, p < 0.001) and with ROS production stimulated with 50 mumol N-formyl, met, leu, phe l-1 (N-FMLP) (r = 0.835, p < 0.001) and 100 nmol phorbol 12-myristate 13-acetate l-1 (PMA) (r = 0.835, p < 0.001) measured using a chemiluminescence assay. Leukocytes were removed from the sperm suspensions of 6 donors and from 96 ejaculates from 21 subfertility patients and ROS production was determined. Subsequently, in all 6 donors, N-FMLP did not stimulate ROS production indicating that leukocyte removal was complete, though in one case PMA stimulated low levels of ROS production. In 65 ejaculates from subfertile men the N-FMLP response was completely eliminated but in 7 of these samples PMA continued to stimulate ROS production. We conclude that infiltrating leukocytes are the predominant source of ROS production in unpurified sperm preparations. Some purified sperm suspensions could be stimulated to produce ROS by the addition of PMA indicating that spermatozoa themselves may produce ROS, albeit in much smaller amounts.
- Published
- 1999
- Full Text
- View/download PDF
39. Prediction of fecundability from semen analysis: problems in providing an accurate prognosis.
- Author
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Ford WC
- Abstract
Information from semen analysis is used to predict the likelihood that a couple will conceive within a period of time. It is only possible to provide a probability; there can be no certainty. The probability is influenced by a host of factors including semen quality, and studies in large groups or using simple models are required to overcome this. Delayed conception from natural intercourse or poor fertilization at IVF has limited predictive power for a subsequent attempt. The problem is made worse by variations in sperm parameters among different ejaculates from the same man and by differences among groups of patients. Results of studies of potential criteria should be presented in a way that allows the effect of the test result on the probability of conception to be appreciated, and results should be confirmed on independent data sets. When there is potential for fertility, estimation of fecundability can only be approximate; however, progress is possible. Effects of semen quality can be clearly identified in large groups, and computer assisted semen analysis measurements do provide useful additional information for the success of intracervical insemination.
- Published
- 1999
- Full Text
- View/download PDF
40. The effect of incubation periods under 95% oxygen on the stimulated acrosome reaction and motility of human spermatozoa.
- Author
-
Whittington K and Ford WC
- Subjects
- Adult, Humans, Male, Oxygen, Reactive Oxygen Species, Acrosome Reaction, Semen Preservation methods, Sperm Motility, Spermatozoa
- Abstract
Human sperm samples were prepared on a 30% Percoll gradient and reactive oxygen species (ROS) production was measured. In samples that generated ROS incubation under 95%O2:5%CO2 for 30 min decreased the proportion of spermatozoa capable of the stimulated acrosome reaction by 40% in comparison to samples incubated under 95%N2:5%CO2 (P< 0.001, repeated measures analysis of variance), but the degree of inhibition did not increase after more prolonged incubation periods (up to 6 h). The addition of the antioxidants catalase and superoxide dismutase prevented the inhibitory effect of 95%O2:5%CO2. Leukocyte removal from samples prior to 95%O2:5%CO2 incubation preserved the ability of the spermatozoa to acrosome react. Sperm motility parameters were less affected by 95%O2:5%CO2 but track velocity was 64.1 microm/s+/-1.96 after 2 h incubation under 95%N2:5%CO2 compared with 54.7 microm/s+/-1.41 after 2 h incubation under 95%O2:5%CO2 (P < 0.05, repeated measures analysis of variance). Sperm samples that did not generate detectable ROS were not affected by 95%O2:5%CO2. The toxic effects of incubation under 95%O2:5%CO2 on human spermatozoa result from increased endogenous ROS production, mostly from leukocytes. High ROS levels inhibit sperm function, with the stimulated acrosome reaction being more susceptible than motility parameters.
- Published
- 1998
- Full Text
- View/download PDF
41. The contribution of subtle oocyte or sperm dysfunction affecting fertilization in endometriosis-associated or unexplained infertility: a controlled comparison with tubal infertility and use of donor spermatozoa.
- Author
-
Hull MG, Williams JA, Ray B, McLaughlin EA, Akande VA, and Ford WC
- Subjects
- Adult, Embryo Implantation, Female, Fertilization in Vitro, Humans, Infertility therapy, Infertility, Female physiopathology, Infertility, Female therapy, Male, Pregnancy, Tissue Donors, Endometriosis complications, Fallopian Tube Diseases complications, Infertility physiopathology, Oocytes physiology, Reproductive Techniques, Spermatozoa physiology
- Abstract
This study aims to determine the relative contribution of oocyte and/or sperm dysfunction to the reduction of fertilization rates in vitro in cases of minor endometriosis and prolonged unexplained infertility. The results of in-vitro fertilization (IVF) treatment with ovarian stimulation have been compared between couples with the above conditions and women with tubal infertility (as control for oocyte function) and the use of donor spermatozoa (as control for sperm function). Fertilization and cleavage rates using husband's spermatozoa were significantly reduced in endometriosis couples (56%, n = 194, P < 0.001) and further significantly reduced in couples with unexplained infertility (52%, n = 327, P < 0.001) compared with tubal infertility (60%, n = 509). Using donor spermatozoa the rates were the same as using husband's spermatozoa in tubal infertility (61%, n = 27) or endometriosis (55%, n = 21) but significantly though only partly improved with unexplained infertility (57%, n = 60, P < 0.02). In unexplained infertility, a significantly increased proportion of couples experienced complete failure of fertilization and cleavage in a cycle (5-6% versus 2-3%). However, complete failure was not usually repetitive, and the affected couples did not account for the overall reduction in fertilization and cleavage rates, which remained significantly lower in the rest of the unexplained and endometriosis groups. Implantation and pregnancy rates appeared similar in all groups. The benefit of IVF treatment in cases of minor endometriosis and prolonged unexplained infertility is due to superabundance of oocytes obtained by stimulation. The reduction in natural fertility associated with endometriosis appears to be at least partly due to a reduced fertilizing ability of the oocyte. In unexplained infertility, there is distinct impairment due to otherwise unsuspected sperm dysfunction but probably also oocyte dysfunction.
- Published
- 1998
- Full Text
- View/download PDF
42. Antioxidant treatment for male subfertility: a promise that remains unfulfilled.
- Author
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Ford WC and Whittington K
- Subjects
- Animals, Female, Humans, Infertility, Male physiopathology, Male, Oxidative Stress, Spermatozoa drug effects, Spermatozoa physiology, Antioxidants therapeutic use, Infertility, Male drug therapy
- Published
- 1998
- Full Text
- View/download PDF
43. Intrauterine insemination: is it an effective treatment for male factor infertility?
- Author
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Ford WC, Mathur RS, and Hull MG
- Subjects
- Cryopreservation, Humans, Infertility, Male diagnosis, Infertility, Male etiology, Male, Randomized Controlled Trials as Topic, Infertility, Male therapy, Insemination, Artificial, Heterologous methods, Insemination, Artificial, Homologous methods
- Abstract
Results were collected from 11 studies comparing intrauterine insemination (IUI) with intracervical insemination (ICI) of frozen donor semen, 10 studies comparing IUI with timed natural intercourse (NI) or ICI in couples with semen defects and seven studies comparing ICI with NI or ICI in couples with unexplained infertility. IUI significantly increased the pregnancy rate relative to favourably timed ICI in donor insemination (DI) with frozen semen both with and without gonadotrophin stimulation of the female partner (odds ratios (95% confidence interval) 1.92 (1.02-3.61) and 2.63 (1.52-4.54) respectively). The benefit of IUI tended to be less when the pregnancy rate for ICI was high and IUI had no benefit with fresh donor semen. Overall IUI was of significant benefit in the male factor couples compared with NI-ICI (odds ratio 2.20 (1.43-3.39) and the advantage appeared to be maintained when comparison was confined to properly timed ICI although the odds ratios were not significantly greater than 1. IUI had no benefit relative to favourably timed NI-ICI for couples with unexplained infertility; an apparent advantage overall was produced by studies where NI was late. None of the studies on male factor used a sperm function test to define male subfertility and three only included couples with good mucus penetration by sperm. The range of semen defects defined was such that many couples would have had a good chance of conceiving naturally given a normal female partner but nevertheless the overall pregnancy rate (4.8%) was considerably less than in the unexplained group (11.6%), suggesting that some sperm dysfunction was present. We conclude that the available evidence suggests that IUI is valuable for DI with cryopreserved semen and for couples with mild to moderately impaired semen quality and postulate that it overcomes failure to fertilize due to impaired mucus penetration and poor survival in the female reproductive tract.
- Published
- 1997
- Full Text
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44. Cloning and sequence analysis of rat fertilin alpha and beta--developmental expression, processing and immunolocalization.
- Author
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McLaughlin EA, Frayne J, Barker HL, Jury JA, Jones R, Ford WC, and Hall L
- Subjects
- ADAM Proteins, Amino Acid Sequence, Animals, Base Sequence, Cloning, Molecular, DNA, Complementary analysis, DNA, Complementary chemistry, DNA, Complementary genetics, Fertilins, Gene Expression Regulation, Developmental, Immunohistochemistry, Male, Molecular Sequence Data, Protein Processing, Post-Translational, Rats, Rats, Wistar, Reproduction genetics, Reproduction physiology, Sequence Analysis, Sequence Homology, Amino Acid, Testis chemistry, Transcription, Genetic, Membrane Glycoproteins genetics, Metalloendopeptidases genetics
- Abstract
Fertilin alpha and beta are members of the MDC (metalloproteinase-like, disintegrin-like, cysteine-rich) protein family and are expressed on the sperm surface where they have been proposed to play a role in mammalian fertilization. Inhibition of sperm-oocyte binding and sperm-oocyte fusion make fertilin an attractive target for the development of an immunocontraceptive vaccine. Full-length cDNAs encoding alpha and beta fertilin subunits were isolated from a rat testis cDNA library and sequenced. Using reverse transcription-polymerase chain reaction (RT-PCR), the developmental expression of fertilin alpha and beta was determined in pre-pubertal and mature rat testes. Fertilin alpha mRNA was present at all stages of development, suggesting that it is not exclusively expressed in post-meiotic germ cells. In contrast, fertilin beta mRNA was first identified in day 19 testes, coincident with the presence of pachytene spermatocytes. Polyclonal antisera raised against a 28-residue peptide (corresponding to part of the disintegrin domain) and two recombinant fusion proteins identified a 90 kDa protein in testicular sperm extracts and a 60 kDa protein in caput and cauda epididymidal sperm extracts, the predicted sizes for rat fertilin beta precursor and mature protein respectively. Indirect immunofluorescence using the anti-peptide antisera stained the acrosomal cap of permeabilized testicular, caput and caudal spermatozoa and elongating spermatids in testicular sections.
- Published
- 1997
- Full Text
- View/download PDF
45. Evidence that peptides derived from the disintegrin domain of primate fertilin and containing the ECD motif block the binding of human spermatozoa to the zona-free hamster oocyte.
- Author
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Gichuhi PM, Ford WC, and Hall L
- Subjects
- ADAM Proteins, Amino Acid Sequence, Animals, Cricetinae, Disintegrins chemistry, Female, Fertilins, Humans, Macaca fascicularis, Male, Membrane Glycoproteins chemistry, Metalloendopeptidases chemistry, Molecular Sequence Data, Oligopeptides chemistry, Oligopeptides pharmacology, Oocytes drug effects, Peptide Fragments chemistry, Peptide Fragments pharmacology, Peptides chemistry, Peptides pharmacology, Spermatozoa drug effects, Zona Pellucida physiology, Disintegrins pharmacology, Membrane Glycoproteins pharmacology, Metalloendopeptidases pharmacology, Oocytes physiology, Sperm-Ovum Interactions drug effects, Spermatozoa physiology
- Abstract
The binding of human spermatozoa to, and penetration of, zona-free hamster oocytes were significantly inhibited in the presence of (i) a 28-residue peptide corresponding to part of the disintegrin-like domain of monkey fertilin beta, or (ii) a hexapeptide containing the ECD motif found in the disintegrin-like domain of monkey and human fertilin beta, or (iii) a hexapeptide containing an RGD motif, implicated in integrin recognition. Polyclonal antibodies raised against the 28-residue peptide were used in conjunction with immunobeads to demonstrate that this peptide bound to the oolemma of zona-free hamster oocytes. These data support the view that the ECD motif is involved in the recognition of the oolemma receptor by human fertilin.
- Published
- 1997
- Full Text
- View/download PDF
46. Reactive oxygen species in human sperm suspensions: production by leukocytes and the generation of NADPH to protect sperm against their effects.
- Author
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Ford WC, Whittington K, and Williams AC
- Subjects
- Humans, Infertility, Male metabolism, Leukocytes chemistry, Leukocytes metabolism, Male, NADP metabolism, Reactive Oxygen Species metabolism, Spermatozoa chemistry
- Abstract
In men from couples consulting for infertility, 72% of washed sperm preparations produced detectable amounts of reactive oxygen species (ROS) compared to only 25% of preparations from a population of fertile donors. High ROS production was associated with oligozoospermia and poor sperm function. The rate of ROS production was closely correlated with the concentration of leukocytes (r = 0.826) and the degrees of stimulation by N-formyl-methionyl-leucyl-phenyl alanine (NFMLP) and by phorbol 12-myristate 13 acetate (PMA) were similar (r = 0.923). The removal of leukocytes with 'Dynabeads' either abolished or substantially decreased ROS production but in a few cases ROS production that could be stimulated by PMA but not NFMLP was observed in leukocyte-free preparations. When sperm preparations which produced ROS were incubated under 95% O2 there was a rapid 40% decrease in the number of sperm that could be stimulated to acrosome react although the acrosome reaction was unaffected by incubation under 95% N2 for up to 6 h. The harmful effect of oxygen was not seen in preparations that produced no ROS and could be prevented by removing leukocytes from the suspension or by adding superoxide dismutase and catalase. We conclude that leukocytes are the predominant source of ROS in human sperm preparations and that the ROS they produce are harmful to sperm. On the other hand these data confirm that highly purified sperm can produce ROS albeit in smaller amounts. We have demonstrated that flux through the pentose phosphate pathway (PPP) in purified sperm preparations increases in response to oxidative stress. This is required to make reduced glutathione available for glutathione peroxidase and we suggest that measurement of PPP flux provides an index of the capacity of glutathione peroxidase to protect sperm against oxidation.
- Published
- 1997
47. The indirect immunobead test for seminal antisperm antibodies and fertilization rates at in-vitro fertilization.
- Author
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Ford WC, Williams KM, McLaughlin EA, Harrison S, Ray B, and Hull MG
- Subjects
- Adult, Female, Humans, Immunoglobulin A analysis, Immunoglobulin G analysis, Immunoglobulin M analysis, Infertility, Female therapy, Male, Autoantibodies analysis, Fertilization in Vitro, Immunoassay methods, Infertility, Male immunology, Infertility, Male therapy, Semen immunology, Spermatozoa immunology
- Abstract
A series of 183 patients with positive indirect immunobead tests on semen was studied to determine the correlation in semen between specific antibody types, binding sites, antibody concentration, and fertilizing ability. IgM was present in only 44 ejaculates and was present in sufficient quantity to cause significant binding to immunobeads (i.e. >20% of motile donor spermatozoa) in only three of them. There was no correlation between the percentages of motile donor spermatozoa that bound IgA and IgG immunobeads but the two classes of beads generally bound to the same region of the spermatozoa. A total of 63 couples went on to attempt in-vitro fertilization (IVF) treatment, all with mature eggs recovered. Of these mature eggs, 44% were fertilized and cleaved normally in comparison to 68% in a group of patients with tubal disease. Fertilization rates in individuals followed a bimodal distribution with a substantial number of couples experiencing zero or very poor rates (0-20%), the mode for the remainder lying between 60 and 80%. The fertilization rate tended to decrease as the amount of antibody increased. The percentage of donor spermatozoa that bound to immunobeads, taken as the greater of IgA and IgG, was selected by logistic regression as a significant predictor of poor fertilization (rate <=25%). The predictive power of the equation was improved by including the motile normal sperm concentration but the equation could only account for a small proportion of the total variation in fertilization rate. The presence of antibodies to the sperm head was highly correlated with the antibody concentration but was not selected as a predictor of fertilization. We conclude that the nature of the antigen against which the seminal antisperm antibody is directed may be as important as the antibody concentration in affecting sperm function. There seems to be little practical value in measuring IgM in seminal plasma.
- Published
- 1996
- Full Text
- View/download PDF
48. Randomized controlled trial of cervical cap with intracervical reservoir versus standard intracervical injection to inseminate cryopreserved donor semen.
- Author
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Coulson C, McLaughlin EA, Harris S, Ford WC, and Hull MG
- Subjects
- Adult, Female, Humans, Injections, Male, Pregnancy, Pregnancy Outcome, Prospective Studies, Cervix Uteri, Cryopreservation, Insemination, Artificial, Heterologous methods, Semen Preservation
- Abstract
A prospective controlled study of donor insemination without sperm preparation or ovarian stimulation was performed to compare the use of a cervical cap incorporating an intracervical reservoir with a standard intracervical injection technique to inseminate 0.5 ml cryopreserved semen. Treatments were alternated in successive cycles in each patient after initial randomized selection. A total of 198 patients had 635 treatment cycles (median 3, range 1-7), 309 with reservoir and 326 by standard injection. A total of 56 women became pregnant, 24 (7.8% per cycle) with the reservoir and 32 (9.8% per cycle) by injection. There were no significant differences between the pregnancy rates per cycle overall or cycle-specific cumulative rates calculated using the life-table method. There were no significant differences in age, parity, baseline gonadotrophin measurements, mid-luteal serum progesterone concentrations, frequency of adverse fertility factors in the woman or her partner's cause of infertility between women who conceived and those who failed to conceive. We conclude that use of a cervical reservoir and cap for donor insemination does not offer any advantage over standard intracervical insemination.
- Published
- 1996
- Full Text
- View/download PDF
49. Intracellular calcium measurements in individual human sperm demonstrate that the majority can respond to progesterone.
- Author
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Plant A, McLaughlin EA, and Ford WC
- Subjects
- Fluorescent Dyes, Fura-2, Humans, Male, Sperm Motility, Calcium metabolism, Progesterone pharmacology, Spermatozoa drug effects, Spermatozoa metabolism
- Abstract
Objective: To determine if human spermatozoa could be immobilized and intracellular calcium measurements made on individual cells to measure what proportion can respond to P., Design: Spermatozoa were loaded with Fura 2 (Sigma Chemical Co., Poole, Dorest, United Kingdom) and suspended in 10% gelatin at 37 degrees C. A thin layer of the suspension was cooled to room temperature (20 degrees C to 25 degrees C) and [Ca2+]i was measured with a fluorescence microscope equipped with dual wavelength excitation and an image analysis system., Setting: University-based laboratory., Participants: Semen was obtained from four fertile donors to a donor insemination program., Interventions: None., Main Outcome Measures: [Ca2+]i was calculated from the ratio of Fura 2 fluorescence excited at 340 nm and that excited at 366 nm., Results: One hundred six of 114 sperm examined (93%) demonstrated a significant response to P but the size and duration of the response was variable., Conclusion: These data demonstrate that most sperm can respond to P.
- Published
- 1995
- Full Text
- View/download PDF
50. Relative influence of serum follicle stimulating hormone, age and other factors on ovarian response to gonadotrophin stimulation.
- Author
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Cahill DJ, Prosser CJ, Wardle PG, Ford WC, and Hull MG
- Subjects
- Adult, Age Factors, Analysis of Variance, Cohort Studies, Female, Fertilization in Vitro, Follicle Stimulating Hormone therapeutic use, Humans, Menstrual Cycle, Buserelin therapeutic use, Follicle Stimulating Hormone blood, Luteinizing Hormone blood, Menotropins therapeutic use, Ovary drug effects
- Abstract
Objective: To determine the relative value of the woman's age, basal follicle stimulating hormone (FSH), basal luteinising hormone (LH) and menstrual cycle pattern (all defined prior to treatment) in predicting the ovarian response to gonadotrophin stimulation for in vitro fertilisation., Design: Open, descriptive cohort study., Patients: One hundred and seventy-one consecutive ovulatory women undergoing their first cycle of in vitro fertilisation with ovarian stimulation after pituitary desensitisation., Interventions: Measurement of basal (early follicular phase) and down-regulated concentrations of serum FSH and LH, and calculation of age at treatment and of median length of menstrual cycles and range of variation prior to treatment., Main Outcome Measures: Duration and amount of gonadotrophin stimulation to achieve follicular maturity, number of mature follicles, peak serum oestradiol concentration and number of mature oocytes, were compared between banded values of variables studied., Results: Increasing basal FSH concentrations were significantly associated with reducing oestradiol levels, numbers of mature follicles and oocyte yield even when the FSH levels were still within the normal range though above average (6 to 8.9 i.u./l). There were similar but weaker associations with FSH levels after down-regulation. There were also significant differences between women over and under 40 years old in their oestradiol levels, numbers of follicles and of oocytes. Analysis of variance showed significant independent association of basal FSH with both oestradiol and numbers of oocytes, but not of age, menstrual pattern, or serum LH concentrations., Conclusion: Serum FSH is more sensitive than the woman's age in determining her ovarian responsiveness to stimulation. LH concentrations and menstrual cycle patterns are unhelpful.
- Published
- 1994
- Full Text
- View/download PDF
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