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A J Rutherford

Publications and source records attributed to A J Rutherford.

At least 37 records · Page 2Linked to original sources
PubMed1998

Survey of the diagnosis and management of antisperm antibodies.

A questionnaire was sent to all Human Fertilization and Embryology Authority-registered reproductive medicine centres throughout the UK to survey their policy for the diagnosis and management of antisperm antibodies. Forty-eight responses were received from the 74 units that use husbands' spermatozoa for treatments (65%). Most centres use at least one test to detect antibodies, although a minority perform no tests on the basis that their clinical practice would be unaltered if antibodies were present. Positive tests are classed as clinically significant at levels varying from > or = 10% to > or = 50% for direct sperm binding tests (mixed antiglobulin reaction, immunobead test), and ranging from any positive reaction to > or = 1:32 for the microtitre tests (gelatin and tray agglutination tests, microimmobilization test). Strategies for managing affected patients include no intervention, artificial insemination and intrauterine insemination (IUI) using spermatozoa prepared by various techniques, in-vitro fertilization (IVF) with or without increased insemination concentration, and intracytoplasmic sperm injection. Criteria for the latter are diverse, some centres managing all antibody-positive patients this way, while others resort to it only in severe cases or after other treatments have failed. Half of the respondents occasionally or regularly employ steroids, either alone or in conjunction with IUI or IVF. Overall, it appears that much confusion exists as to how best to manage couples presenting with antibody-related infertility.

Adult↗
PubMed1998

Metabolism of pyruvate by the early human embryo.

Pyruvate is added to all media used for human in vitro fertilization and embryo culture, but its function(s) in the early embryo is unknown. We tested the possibility that pyruvate can act as an oxidizable energy source by measuring the consumption of pyruvate and oxygen by Day 2 and Day 3 human embryos, using microfluorometric techniques. Oxygen consumption (19.6 pmol/embryo per hour) could account for the oxidation of only 56% of the pyruvate consumed (13.9 pmol/embryo per hour). Oxygen was also consumed in the absence of exogenous substrates. Lactate appeared in the incubation medium with pyruvate (0.47 mM) as sole exogenous substrate at a rate of 12.1 pmol/embryo per hour, at a similar rate (10.85 pmol/embryo per hour) in the presence of 1 mM glucose and 0.47 mM pyruvate, and at 2.25 pmol/embryo per hour in the absence of exogenous substrates, suggesting that a high proportion of the pyruvate taken up by early human embryos is converted to lactate. Pyruvate uptake in the presence of UK5099, a pyruvate transport inhibitor, was reduced to 10% of control values, consistent with the presence of the monocarboxylate carrier in the human embryo plasma membrane.

Acrylates↗
PubMed1997

Human tubal fluid: production, nutrient composition and response to adrenergic agents.

Vascularly perfused Fallopian tubes have been used to study the formation and composition of human tubal fluid and the response to adrenergic agents. An artery serving the tube was cannulated and perfused with Medium 199 supplemented with bovine serum albumin (BSA) and antibiotics. A second cannula was attached to the fimbriated end for native tubal fluid collection. The preparation was viable for up to 2 h. Tubal fluid was only obtained in tubes removed in the proliferative and early secretory phases of the ovarian cycle. Isoproterenol (1 mM) added to the perfusate stimulated fluid production, whereas dibutyryl cyclic AMP (1 mM) reduced fluid formation by 66%. Glucose, pyruvate and lactate concentrations in tubal fluid, measured by microfluorescence assays, were 1.11, 0.14 and 5.4 mM respectively. The concentrations of 17 amino acids in tubal fluid were measured by high performance liquid chromatography following fluorescence derivatization. Arginine (0.19 mM) > alanine (0.11 mM) > glutamate (0.09 mM) were present in highest concentration in all phases of the cycle. All 17 amino acid concentrations in tubal fluid were below those in the vascular perfusate. These data provides the basis for a culture medium whose composition mimics the physiological environment to which early human embryos are exposed.

Adrenergic beta-Agonists↗
PubMed1995

Autoantibodies and antisperm antibodies in sera and follicular fluids of infertile patients; relation to reproductive outcome after in-vitro fertilization.

Immune reactions have effects at various concentrations in the reproductive process and autoantibodies may have an impact on fertility and the outcome of assisted conception. We measured the prevalence of and relation between antibodies to smooth muscle, nuclear, phospholipid and sperm antigens, and concentrations of immunoglobulins G, M and A and complement components C3 and C4, in the sera and follicular fluids of women with unexplained infertility (n = 30), endometriosis (n = 20), tubal infertility (n = 50) and the sera of 20 normal non-pregnant women. We assessed fertilization and successful pregnancy rates in relation to antibody status of infertile women after in vitro fertilization. All antibodies had a higher prevalence in infertile women compared with controls and this was significant for smooth muscle antibody in endometriosis (P < 0.05); anticardiolipin antibody in tubal infertility (P < 0.05); and antisperm antibody in all types of infertility (P < 0.001). There was no relation between presence of specific antibodies in serum or between serum and follicular fluids. Total biochemical pregnancy rate was higher with endometriosis (P = 0.05) but clinical pregnancy and live birth rates did not differ between groups or in relation to antibody status. Significant differences in immunoglobulin and complement components occurred in women with and without successful biochemical pregnancy.

Adult↗
PubMed1995

Follicular volume and number during in-vitro fertilization: association with oocyte developmental capacity and pregnancy rate.

This study examined the effect of the number of follicles aspirated during egg retrieval on pregnancy likelihood during an ovulation induction, in-vitro fertilization (IVF) programme. In addition, the volume of each individual follicle was related to the probability of obtaining an oocyte from that follicle. Its capacity to be fertilized, the incidence of polyspermic fertilization, the quality of early embryos derived from that oocyte and the influence of patient age were the other outcomes studied. Large follicular number and high mean follicular volume related positively to pregnancy outcome. Successful egg retrieval, normal fertilization and good embryo quality were more likely with increasing individual follicular volume. A model was constructed to quantify the predictive value of follicular fluid volume on the developmental potential of individual oocytes and embryos derived from that follicle. Successful outcome of IVF is more likely if ovulation induction results in many follicles, particularly if they have a high mean volume. Individual oocyte and embryo quality can be traced back to the follicular level.

Adult↗
PubMed1995

Human tubal fluid: formation and composition during vascular perfusion of the fallopian tube.

A vascularly perfused preparation of the Fallopian tube has been developed as a model to study the formation and composition of human tubal fluid. An artery serving the tube was cannulated and perfused at a rate of 0.7 ml/min for 1 h with Medium 199 supplemented with bovine serum albumin, heparin and antibiotics. A cannula was also inserted into the lumen. Light and scanning electron micrographs of control and perfused tubes showed that the epithelial lining was intact after perfusion. Tubal fluid was collected in 13 out of 19 experiments. Fluid could always be collected from patients who were in the follicular phase of their ovarian cycle. The mean rate of appearance was 48 microliters/h. The glucose, lactate and pyruvate concentrations in the tubal fluid, as assessed by fluorescence microanalysis, were 0.53, 8.58 and 0.17 mM respectively. There were no correlations between metabolite concentration and the length of perfusion, cannulation time, patient's age or condition. This technique provides a controlled method with which to access and examine human tubal fluid and will allow the physiology of both healthy and diseased tubes to be studied.

Adult↗
PubMed1995

Simultaneous DNA 'fingerprinting', diagnosis of sex and single-gene defect status from single cells.

Sex and cystic fibrosis status have been previously diagnosed separately at the single cell level. We have developed a sensitive, reliable, accurate and rapid (within 5-6 h) system for the simultaneous diagnosis of sex, cystic fibrosis and a DNA 'fingerprint' within a single reaction from a variety of single cells. As contamination cannot be totally excluded, particularly at the single cell level, DNA 'fingerprinting' can be used to assess the risk of contamination. High sensitivity with single cells is combined with very high specificity (estimated matching probability of 10(-7)-10(-8)), allowing the source of the amplified cell to be identified with a very high degree of probability. Fluorescent primers were multiplexed for six tetranucleotide microsatellite sequences to determine the DNA fingerprint; the amelogenin gene was used to diagnose sex, and primers for the CFTR region were used to determine cystic fibrosis (CF) status. Analysis of the fluorescent product was undertaken using an automated DNA sequencer with Genescan software. This technique has many applications such as prenatal and preimplantation diagnosis, forensic identification of small or degraded samples, and detection of contamination sources. DNA fingerprints of single haploid spermatozoa and other cells can be assessed, so ensuring the detection of both diploid and haploid contamination during preimplantation diagnosis.

Cystic Fibrosis↗
PubMed1989

Organ donation from intensive care units in England.

OBJECTIVE: To audit all deaths in intensive care units (excepting coronary care only and neonatal intensive care units) in England to assess potential for organ procurement. DESIGN: An audit in which 14 regional health authorities and London special health authorities each designated a regional liaison officer to identify intensive care units and liaise with Department of Health and the Medical Research Council's biostatistics unit in distribution, return, and checking of audit forms. Audit took place from 1 January to 31 March 1989 and will continue to 31 December 1990. SETTING: 278 Intensive care units in England. PARTICIPANTS: Colleagues in intensive care units (doctors, nurses, coordinators, and others), who completed serially numbered audit forms for all patients who died in intensive care. RESULTS: The estimated number of deaths in intensive care units was 3085, and validated audit forms were received for 2853 deaths (92%). Brain stem death was a possible diagnosis in only 407 (14%) patients (about 1700 cases a year) and was confirmed in 282 (10%) patients (an estimated 1200 cases a year). Half the patients (95% confidence interval 45% to 57%) in whom brain stem death was confirmed became actual donors of solid organs. Tests for brain stem death were not performed in 106 (26%) of 407 patients with brain stem death as a possible diagnosis, and general medical contraindication to organ donation was recorded for 48 (17%) of 282 patients who fulfilled brain stem death criteria before cessation of heart beat. The criteria were fulfilled before cessation of heart beat and in the absence of any general medical contraindication to organ donation in 234 patients, 8% of those dying in intensive care (an estimated 1000 cases a year). Consent for organ donation was given in 152 (70%) of 218 cases (64% to 76%) when the possibility of organ donation was suggested to relatives. In only 14 out of 232 families (6%; 3% to 9%) was there no discussion of organ donation with relatives. Corneal suitability was recorded as "not known" in a high proportion (1271; 45%) of all deaths and intensive care units reported only 123 corneal donors (4% of all audited deaths). CONCLUSION: When brain stem death is a possible diagnosis tests should always be carried out for confirmation. Early referral to the transplant team or coordinator should occur in all cases of brain stem death to check contraindications to organ donation. There should be increased use of asystolic kidney donation, and patients should be routinely assessed for suitability for corneal donation. Finally, more publicity and education are necessary to promote consent.

Aged↗
PubMed1989

Non-invasive measurement of glucose and pyruvate uptake by individual human oocytes and preimplantation embryos.

Pyruvate and glucose uptake by 73 individual human oocytes and preimplantation embryos was measured non-invasively, using an ultramicrofluorescence assay to analyse changes in substrate levels in microdroplets of culture medium. The uptake of both substrates was measured over successive daily incubations between days 1 (unfertilized oocytes) or 2 ('spare' embryos which were not transferred) and day 6 (day 0 = day of insemination). Under these conditions, 58% (25/43) of fertilized embryos with two pronuclei on day 1 developed to the blastocyst stage by day 6. The pyruvate uptake of these embryos increased from approximately 28 to a maximum of 40 pmol/embryo/h between days 2.5 and 4.5. Similarly, glucose uptake increased from approximately 8 to 14 pmol/embryo/h between days 2.5 and 4.5, but then increased further to 24 pmol/embryo/h on day 5 at the blastocyst stage. [corrected] The pyruvate uptake of fertilized embryos which arrested at cleavage stages was significantly lower than for those which developed to the blastocyst stage. Polyspermic and parthenogenetic embryos, and unfertilized oocytes also had lower pyruvate uptakes at later stages. The glucose uptake of unfertilized oocytes and abnormal embryos never reached the level of fertilized embryos at the blastocyst stage on day 5.5. Non-invasive measurement of pyruvate uptake before embryo transfer may provide a valuable functional criterion for the selection of viable embryos capable of developing to the blastocyst stage.

Blastocyst↗
PubMed1989

Vaginal pH in pregnancy in women delivered at and before term.

A microelectrode was used to measure vaginal pH in a longitudinal study during pregnancy in 30 women, 28 of whom were delivered at term. Excluding pH readings made in the presence of pathogenic organisms, 120 readings were taken. The mean vaginal pH of all subjects was 4.16 (SD 0.41). Analysis of variance showed no significant within-subject variation of pH during pregnancy. Two women had spontaneous preterm deliveries (less than 37 weeks) and their mean vaginal pH during pregnancy was 5.05 and 5.06. Eight women admitted in preterm labour, who then gave birth, had a mean pH of 5.43 (SD 0.94) which was significantly higher than the mean pH of 10 women in labour at term (4.58, SD 0.59). The relation between bacterial growth in vitro and the surrounding pH was also examined. Escherichia coli, a potential pathogen, behaved differently from both Lactobacillus (a commensal organism) and Candida albicans. The clinical observations show a trend towards higher vaginal pH values in association with preterm labour.

Female↗