Sorption of PFOS in 114 Well-Characterized Tropical and Temperate Soils: Application of Multivariate and Artificial Neural Network Analyses.

The influence of soil properties on PFOS sorption are not fully understood, particularly for variable charge soils. PFOS batch sorption isotherms were conducted for 114 temperate and tropical soils from Australia and Fiji, that were well-characterized for their soil properties, including total organic carbon (TOC), anion exchange capacity, and surface charge. In most soils, PFOS sorption isotherms were nonlinear. PFOS sorption distribution coefficients (Kd) ranged from 5 to 229 mL/g (median: 28 mL/g), with 63% of the Fijian soils and 35% of the Australian soils showing Kd values that exceeded the observed median Kd. Multiple linear regression showed that TOC, amorphous aluminum and iron oxides contents, anion exchange capacity, pH, and silt content, jointly explained about 53% of the variance in PFOS Kd in soils. Variable charge soils with net positive surface charges, and moderate to elevated TOC content, generally displayed enhanced PFOS sorption than in temperate or tropical soils with TOC as the only sorbent phase, especially at acidic pH ranges. For the first time, two artificial neural networks were developed to predict the measured PFOS Kd (R2 = 0.80) in the soils. Overall, both TOC and surface charge characteristics of soils are important for describing PFOS sorption.

Steroid profiles by liquid chromatography-mass spectrometry of matched serum and single dominant ovarian follicular fluid from women undergoing IVF.

RESEARCH QUESTION: Can IVF outcomes be predicted from the steroid profile generated by liquid chromatography-mass spectrometry (LC-MS/MS) from follicular fluid collected from a single dominant follicle and serum after ovarian stimulation. DESIGN: Prospective observational cohort study in which serum and follicular fluid were collected from women and used to generate steroid profiles by LC-MS/MS. A total of 93 consecutive women enrolled for IVF treatment were recruited at the Fertility Unit, Royal Prince Alfred Women and Babies Hospital, Sydney between September 2014 and July 2015. Baseline and serum levels at oocyte retrieval, as well as follicular fluid samples from the largest single antral follicle, were collected. All samples underwent steroid analysis within a single batch to measure progesterone (P4), oestradiol (E2), oestrone (E1), dehydroepiandrosterone (DHEA), androstenedione (A4), testosterone (T), dihydrotestosterone (DHT), and 3 α, 5α androstanediol (3α-diol) and 3ß, 5α androstanediol (3ß-diol). RESULTS: P4, E2, E1, A4, T, DHEA and A4 were detectable in all baseline serum levels, at oocyte retrieval and in follicular fluid samples, whereas DHT, 3α-diol and 3ß-diol were only detectable in a minority of samples. The most consistent predictor of pre-transfer (number of follicles >14mm in diameter, oocytes retrieved or fertilized, day-5 blastocysts) outcomes was baseline serum anti-Müllerian hormone. In follicular fluid, E2 was a negative predictor of the number of oocytes retrieved and the number of day-5 blastocysts but no follicular fluid steroids predicted pregnancy outcome. CONCLUSIONS: None of the nine steroids measured in follicular fluid predicted pregnancy outcome in women undergoing IVF.

Linking sleep disturbance to idiopathic male infertility.

Recently published data suggests that male fertility has declined over the past four decades. The reasons for the decline are unclear with up to 50% of cases of male infertility remaining unexplained (idiopathic male infertility). Whilst environmental factors and rising rates of obesity have been implicated, there is now growing evidence that sleep disturbance may be an independent causative factor. Indeed, the prevalence of sleep disturbance appears to be increasing in parallel with deterioration in population sperm quality, a commonly used surrogate marker of male fertility. Although there is some understanding of the relationship between sleep, gonadal hormone secretion and sexual function, it remains to be seen whether sleep disturbance is implicated in idiopathic male infertility. This review will detail the current evidence supporting a link between sleep disturbance and male infertility. Potential mechanistic pathways will be proposed and evidence supporting these pathways will be discussed. Further research is needed in clarifying links between sleep disturbance and idiopathic male infertility. At present the only available treatment option for men with idiopathic infertility is assisted reproductive technology. Demonstration of a causative link between sleep disturbance and idiopathic male infertility may in the future lead to additional treatment options in selected cases.

Continuous improvement in national ART standards by the RTAC accreditation system in Australia and New Zealand.

BACKGROUND: Assisted reproductive technology (ART) clinics in Australia and New Zealand are accredited and licensed against a Code of Practice audited by certifying bodies accredited by the Joint Accreditation System for Australia and New Zealand (JAS-ANZ). The system is administered by the Reproductive Technology Accreditation Committee (RTAC) of the Fertility Society of Australia. AIMS: To review the incidence of variances and findings identified by certifying bodies in Australian and New Zealand ART clinics within the currency of a single version of the Code of Practice. METHODS: Retrospective analysis of certifying body findings against the RTAC Code of Practice incorporating 15 Critical Criteria audited annually and 16 Good Practice Criteria including a Quality Management System audited over a three year cycle. RESULTS: The incidence of clinics with variances against the Critical Criteria fell from 77 to 14% over two years, as did the mean number of variances per clinic which fell from 1.54 to 0.14. CONCLUSIONS: Implementation of the RTAC accreditation system in Australia and New Zealand has contributed to steady improvement in standards and a reduction in risk in ART treatments.

Population trends and live birth rates associated with common ART treatment strategies.

STUDY QUESTION: Have ART live birth rates improved in Australia over the last 12 years? SUMMARY ANSWER: There were striking improvements in per-cycle live birth rates observed for frozen/thaw embryo transfers, blastocyst transfer and single embryo transfer (SET), while live birth rates following ICSI were lower than IVF for non-male factor infertility in most years. WHAT IS ALREADY KNOWN: ART and associated techniques have become the predominant treatment of infertility over the past 30 years in most developed countries. However, there are differences in ART laboratory and clinical practices, and success rates worldwide. Australia has one of the highest ART utilization rates and lowest multiple birth rates in the world, thus providing a unique setting to investigate the contribution of common ART strategies in an unrestricted population of patients to ART success rates. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study of 585 065 ART treatment cycles performed in Australia between 2002 and 2013 using the Australian and New Zealand Assisted Reproduction Database (ANZARD). PARTICIPANTS MATERIALS, SETTING, METHOD: An unrestricted population of all women who underwent autologous ART treatment between 2002 and 2013. Visual descriptive analysis was used to assess the trends in ART procedures by the calendar years. Adjusted odds ratios (aORs) of a live birth for four common ART techniques were calculated after controlling for important confounders including female age, infertility diagnosis, stage of the embryo (blastocyst versus cleavage stage), type of embryo (fresh versus thawed), fertilization method (IVF versus ICSI) and number of embryos transferred (SET versus multiple embryos). MAIN RESULTS AND THE ROLE OF CHANCE: The overall live birth rate per embryo transfer increased from 19.2% in 2002 to 23.3% in 2013 (21.9-24.3% for fresh embryo transfers and 14.6-23.3% for frozen/thaw embryo transfers). This occurred concurrently with an increase in SET from 29.7% to 78.9%, and an increase in the average age of women undergoing treatment from 35.0 to 35.9 years. Individuals who had a frozen/thaw embryo transfer cycle in 2002 had 43% (aOR: 0.57, 95% CI: 0.53-0.61) reduced odds of a live birth compared with a fresh embryo transfer cycle. This contrasted with 16% (aOR: 0.84, 95% CI: 0.80-0.98) reduced odds of a live birth from frozen/thaw embryo transfer cycles in 2013. In 2013, the odds of blastocyst transfer resulting in a live birth were more than twice as great as for cleavage stage transfer (aOR 2.01, 95% CI: 1.92-2.11). The adjusted odds of live birth per SET compared with multiple embryo transfer increased significantly over the last 12 years, from a 38% reduced odds of a live birth follow SET in 2002 (aOR: 062, 95% CI: 0.57-0.67) compared to an 8% reduced odds in 2013 (aOR: 0.92, 95% CI: 0.87-0.98). The aOR of a live birth using ICSI compared to IVF in non-male factor patients was lower in most years bringing into question its widespread use. LIMITATION, REASONS FOR CAUTION: This is a retrospective cohort analysis and cannot confirm causality. High-level evidence on the effectiveness of particular ART techniques, particularly ICSI and blastocyst culture, requires prospective randomized controlled trials or detailed statistical analysis using large-scale data that counts for fertilization failure, embryo loss, prognostic factors and cycle characteristics. WIDER IMPLICATION OF THE FINDINGS: The most striking improvements in ART success rates in Australia have been observed for frozen/thaw embryo transfers, blastocyst transfer and SET. Further studies of the role of ICSI in non-male factor infertility and blastocyst transfer success rates that take into account embryo loss are needed. STUDY FUNDING/COMPETING INTERESTS: No funding was received to undertake this study. The authors declare that they do not have competing interests with this study. TRIAL REGISTRATION NUMBER: NA.

Socio-economic disparities in access to assisted reproductive technologies in Australia.

Women from disadvantaged socio-economic groups access assisted reproductive technology treatment less than women from more advantaged groups. However, women from disadvantaged groups tend to start families younger, making them less likely to suffer from age-related subfertility and potentially have less need for fertility treatment. Whether socio-economic disparities in access to assisted reproductive technology treatment persist after controlling for the need for treatment, has not been previously explored. This population based study demonstrates that socio-economic disparities in access to assisted reproductive technology treatment persist after adjusting for several confounding factors, including age at first birth (used as a measure of delayed childbearing, hence a proxy for need for fertility treatment), geographic remoteness and Australian jurisdiction. Assisted reproductive technology access progressively decreased as socio-economic quintiles became more disadvantaged, with a 15.8% decrease in access in the most disadvantaged quintile compared with the most advantaged quintile after controlling for confounding factors. The adjusted rate of access to assisted reproductive technology treatment also decreased by 12.3% for women living in regional and remote areas compared with those in major cities. These findings indicate that financial and sociocultural barriers to assisted reproductive technology treatment remain in disadvantaged groups after adjusting for need.

Use of the CryoPredict algorithm to predict live birth from cryopreserved embryos.

BACKGROUND: Currently, the viability of cryostored blastocysts that are subsequently re-warmed is determined via the percentage of cell survival. However, the large number of cells that forms the blastocyst can make this estimate difficult and unreliable. Studies have shown that fast re-expanding blastocysts have superior pregnancy rates. AIM: To determine whether the degree and speed of blastocoele re-expansion following cryopreservation and warming correlate with rates of live birth. MATERIALS AND METHODS: A retrospective cohort study of 757 frozen embryo transfer cycles over a 4-year period at Royal Prince Alfred Hospital, Sydney. Clinical and embryology notes were retrieved. Details regarding patient demographics, stimulation cycle from which embryos were derived, frozen embryo transfer cycles, embryology and pregnancy outcomes were recorded. RESULTS: Female (P = 0.01) and male age (P = 0.02) at the time of embryo creation were inversely associated with live birth. Fertilisation method (P = 0.03), embryo type at cryopreservation (P = 0.009), embryo grade at cryopreservation (P < 0.0001), percentage of cell survival post-thaw (P < 0.0001) and the degree of re-expansion (P = 0.003) were the IVF and embryology factors significantly associated with live birth. A predictive model (CryoPredict) was created in order to individualise the probability that the transfer of a given embryo would result in live birth. CONCLUSIONS: The degree and speed of blastocoele re-expansion postcryopreservation and subsequent warming can be used in conjunction with other parameters to predict live birth.

Gestational surrogacy in Australia 2004-2011: treatment, pregnancy and birth outcomes.

BACKGROUND: Information on gestational surrogacy arrangement and outcomes is limited in Australia. AIMS: This national population study investigates the epidemiology of gestational surrogacy arrangement in Australia: treatment procedures, pregnancy and birth outcomes. MATERIALS AND METHODS: A retrospective study was conducted of 169 intended parents cycles and 388 gestational carrier cycles in Australia in 2004-2011. Demographics were compared between intended parents and gestational carrier cycles. Pregnancy and birth outcomes were compared by number of embryos transferred. RESULTS: Over half (54%) intended parents cycles were in women aged <35 years compared to 38% of gestational carrier cycles. About 77% of intended parents cycles were of nulliparous women compared to 29% of gestational carrier cycles. Of the 360 embryo transfer cycles, 91% had cryopreserved embryos transferred and 69% were single-embryo transfer (SET) cycles. The rates of clinical pregnancy and live delivery were 26% and 19%, respectively. There were no differences in rates of clinical pregnancy and live delivery between SET cycles (27% and 19%) and double-embryo transfer (DET) cycles (25% and 19%). Five of 22 deliveries following DET were twin deliveries compared to none of 48 deliveries following SET. There were 73 liveborn babies following gestational surrogacy treatment, including 9 liveborn twins. Of these, 22% (16) were preterm and 14% (10) were low birthweight. Preterm birth was 13% for liveborn babies following SET, lower than the 31% or liveborn babies following DET. CONCLUSIONS: To avoid adverse outcomes for both carriers and babies, SET should be advocated in all gestational surrogacy arrangements.

The original Beckman Coulter Generation II assay significantly underestimates AMH levels compared with the revised protocol.

PURPOSE: Anti-Müllerian hormone (AMH) is used as a marker for ovarian reserve. Since 2011, the standard test for AMH has been the Beckman Coulter Generation (Gen) II assay. However, in July 2013, the protocol was revised due to falsely low readings. The aim of this study was to compare AMH levels measured with the original and revised Gen II assay and to establish a fertile female reference range for the revised protocol. METHODS: Serum AMH levels were measured for 492 natural conception first trimester pregnant women using the original and revised Gen II assay. RESULTS: The original protocol significantly underestimated AMH levels compared with the revised protocol (p < 0.001), the median being 8.4 and 14.2 pmol/L, respectively. In all samples with detectable AMH levels, the revised protocol yielded a higher concentration compared with the original protocol, the magnitude shift ranging from 3.4 to 283.3 % (median 68.0 %). AMH levels measured with the revised protocol were collated to generate an age-specific reference range, with median levels peaking at 27 years then declining with advancing age. The median AMH concentration for ages 20-24 was 17.3 pmol/L, ages 25-29 was 20.5 pmol/L, ages 30-34 was 17.8 pmol/L, ages 35-39 was 10.8 pmol/L, and ages 40-44 was 6.1 pmol/L. CONCLUSIONS: Our study demonstrated that the original Gen II assay significantly underestimated AMH levels, suggesting caution is required when interpreting literature and testing results achieved with this assay. We also established the revised Gen II assay reference range for AMH in women with unassisted proven fertility.

Embryo vitrification using a novel semi-automated closed system yields in vitro outcomes equivalent to the manual Cryotop method.

STUDY QUESTION: Can the equilibration steps prior to embryo vitrification be automated? SUMMARY ANSWER: We have developed the 'Gavi' system which automatically performs equilibration steps before closed system vitrification on up to four embryos at a time and gives in vitro outcomes equivalent to the manual Cryotop method. WHAT IS KNOWN ALREADY: Embryo cryopreservation is an essential component of a successful assisted reproduction clinic, with vitrification providing excellent embryo survival and pregnancy outcomes. However, vitrification is a manual, labour-intensive and highly skilled procedure, and results can vary between embryologists and clinics. A closed system whereby the embryo does not come in direct contact with liquid nitrogen is preferred by many clinics and is a regulatory requirement in some countries. STUDY DESIGN, SIZE, DURATION: The Gavi system, an automation instrument with a novel closed system device, was used to equilibrate embryos prior to vitrification. Outcomes for embryos automatically processed with the Gavi system were compared with those processed with the manual Cryotop method and with fresh (non-vitrified) controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: The efficacy of the Gavi system (Alpha model) was assessed for mouse (Quackenbush Swiss and F1 C57BL/6J x CBA) zygotes, cleavage stage embryos and blastocysts, and for donated human vitrified-warmed blastocysts. The main outcomes assessed included recovery, survival and in vitro embryo development after vitrification-warming. Cooling and warming rates were measured using a thermocouple probe. MAIN RESULTS AND THE ROLE OF CHANCE: Mouse embryos vitrified after processing with the automated Gavi system achieved equivalent in vitro outcomes to that of Cryotop controls. For example, for mouse blastocysts both the Gavi system (n = 176) and manual Cryotop method (n = 172) gave a 99% recovery rate, of which 54 and 50%, respectively, progressed to fully hatched blastocysts 48 h after warming. The outcomes for human blastocysts processed with the Gavi system (n = 23) were also equivalent to Cryotop controls (n = 13) including 100% recovery for both groups, of which 17 and 15%, respectively, progressed to fully hatched blastocysts 48 h after warming. The cooling and warming rates achieved with the Gavi system were 14 136°C/min and 11 239°C/min, respectively. LIMITATIONS, REASONS FOR CAUTION: Testing of the Gavi system described here was limited to in vitro development of embryos from two mouse strains and a limited number of human embryos. Validation of Gavi system advanced production models is now required to confirm the success of semi-automated vitrification, including clinical evaluation of pregnancy outcomes from the transfer of Gavi vitrified-warmed human embryos. WIDER IMPLICATIONS OF THE FINDINGS: The Gavi system has the potential to revolutionize and standardize vitrification of embryos and oocytes. The success of the Gavi system shows that it is possible to semi-automate complicated labour-intensive ART methods and processes, and opens up the possibility for further improvements in clinical outcomes and efficiencies in the ART clinic. STUDY FUNDING/COMPETING INTERESTS: This study was funded by Genea Ltd. S.B., N.M.T., T.T.P., S.J.M., M.C.B. and T.S. are shareholders of Genea Ltd. E.V., C.H., C.L., S.R.L. and S.M.D. are shareholders of Planet Innovation Pty Ltd. The remaining authors are employees of either Genea Ltd. or Planet Innovation Pty Ltd.

Single-embryo transfer of vitrified-warmed blastocysts yields equivalent live-birth rates and improved neonatal outcomes compared with fresh transfers.

OBJECTIVE: To compare pregnancy and neonatal outcomes after fresh and vitrified-warmed single-blastocyst transfers. DESIGN: Retrospective study. SETTING: Private in vitro fertilization (IVF) clinic. PATIENT(S): 1,209 infertile patients who underwent a total of 1,157 fresh and 645 vitrified-warmed embryo transfers. INTERVENTION(S): Day-5 single-blastocyst transfers using fresh or vitrified-warmed (Cryotop method) grade I and grade II embryos. MAIN OUTCOME MEASURE(S): Fetal heart pregnancy rate, live-birth rate, gestational age, and live-birth weight. RESULT(S): The overall blastocyst thaw survival rate was 94.4% and was not significantly different between blastocyst grades or developmental stages. Similar clinical outcomes were achieved for fresh and vitrified-warmed blastocyst transfers; for example, grade I blastocysts had a live-birth rate of 52.8% versus 55.3%, respectively, and grade II blastocysts had a rate of 34.9% versus 30.4%, respectively. Significantly improved neonatal outcomes were evident for vitrified-warmed blastocyst transfers for gestational age, being on average 0.3 weeks longer, and for live-birth weight with babies born on average 145 g heavier (3,296 g versus 3,441 g for fresh and vitrified-warmed groups, respectively), as compared with fresh transfers. CONCLUSION(S): Embryo transfer of vitrified-warmed blastocysts yields equivalent live-birth rates and improved neonatal outcomes compared with fresh transfers.

Effect of soil type on distribution and bioaccessibility of metal contaminants in shooting range soils.

Shooting ranges from Department of Defence sites around Australia were investigated for extent of metal contamination. Shooting range soils contained concentrations ranging from 399 to 10,403 mg/kg Pb, 6.57 to 252 mg/kg Sb, 28.7 to 1250 mg/kg Cu, 5.63 to 153 mg/kg Zn, 1.35 to 8.8 mg/kg Ni and 3.08 to 15.8 mg/kg As. Metal(loid)s were primarily concentrated in the stop butt and the surface soil (0-10 cm). The distribution of contamination reflected firing activity, soil properties, climate and management practices. Climatic variations among sites in Australia are significant, with a temperate climate in the south and tropical climate with high rainfall in the north. Up to 8% of total Pb resided in soil fines (<0.075 mm), due to the fragmentation of bullets on impact. Distribution and bioaccessibility varied between each site. Acidic Townsville soil had the highest proportion of water extractable Pb at 10%, compared to the alkaline Murray Bridge with only 2% Pb water extractable. Soil properties such as CEC, pH and dissolved organic carbon influence mobility. This is reflected in the subsoil concentrations of Pb in Townsville and Darwin which are up to 30 and 46% of surface concentration in the subsoil respectively. Similarly bioaccessibility is influenced by soil properties and ranges from 46% in Townsville to 70% in Perth. Acidic pH promotes dissolution of secondary minerals and the downward movement of Pb in the profile. The secondary Pb minerals formed as a result of weathering in these soils were cerussite, hydrocerussite, pyromorphite, galena and anglesite. Copper oxide was also reported on fragments from bullet jackets. These results have implications for range management.

Monitored natural attenuation of a long-term petroleum hydrocarbon contaminated sites: a case study.

This study evaluated the potential of monitored natural attenuation (MNA) as a remedial option for groundwater at a long-term petroleum hydrocarbon contaminated site in Australia. Source characterization revealed that total petroleum hydrocarbons (TPH) as the major contaminant of concern in the smear zone and groundwater. Multiple lines of evidence involving the geochemical parameters, microbiological analysis, data modelling and compound-specific stable carbon isotope analysis all demonstrated natural attenuation of hydrocarbons occurring in the groundwater via intrinsic biodegradation. Groundwater monitoring data by Mann-Kendall trend analysis using properly designed and installed groundwater monitoring wells shows the plume is stable and neither expanding nor shrinking. The reason for stable plume is due to the presence of both active source and natural attenuation on the edge of the plume. Assuming no retardation and no degradation the contaminated plume would have travelled a distance of 1,096 m (best case) to 11,496 m (worst case) in 30 years. However, the plume was extended only up to about 170 m from its source. The results of these investigations provide strong scientific evidence for natural attenuation of TPH in this contaminated aquifer. Therefore, MNA can be applied as a defensible management option for this site following significant reduction of TPH in the source zone.

What next for preimplantation genetic screening (PGS)? Experience with blastocyst biopsy and testing for aneuploidy.

Blastocysts more commonly have a normal karyotype than cleavage-stage embryos do. Moreover, blastocysts have also made a metabolic transition from catabolism and recycling of the oocyte's reserves and resources, processes that fuel the first 3 days of cleavage. Although not all blastocysts are karyotypically equal, it is still to be determined to what extent a mosaic karyotype might be a normal feature among embryos, both at the cleavage stage and the blastocyst stage--and when looking for karyotypic abnormalities by embryo biopsy might help the chance of implantation rather than harm it. It is also still impractical to look at all the chromosomes that can, through their aneuploidy, stand in the way of successful embryonic and fetal development. We report a randomized clinical trial of blastocyst biopsy followed by preimplantation genetic screening (PGS) for aneuploidy using 5-colour FISH. The trial was suspended and then terminated early when we were unable to show an advantage for PGS. If we are correct in assuming that mitotic non-disjunction is common by the stage of the blastocyst (and that it is much less ominous than meiotic non-disjunction), then further studies of effective PGS of blastocysts for aneuploidy require methods of analysis that cover all the chromosomes and can differentiate the triallelic and monoallelic states of meiotically derived aneuploidies from the biallelic state of mitotic aneuploidies.

Elective transfer of single fresh blastocysts and later transfer of cryostored blastocysts reduces the twin pregnancy rate and can improve the in vitro fertilization live birth rate in younger women.

OBJECTIVE: To determine the extent to which embryo selection by blastulation and elective single blastocyst transfer, supported by efficient cryostorage of spare embryos, can reduce multiple pregnancies and maintain or improve on the live birth rate from IVF. DESIGN: Prospective, nonrandomized cohort study. SETTING: Sydney IVF, a private clinic in Australia. PATIENT(S): In vitro fertilization patients aged <38 years with three or more usable blastocyst, recruited from April 2000 through December 2001, with pregnancies followed up until August 2004. INTERVENTION(S): Blastocysts were cultured and cryostored with stage-specific culture medium and low oxygen conditions. MAIN OUTCOME MEASURE(S): Fetal heart-positive twin pregnancy rate and accumulating "take-home baby" rate per retrieval leading to blastocyst transfer. RESULT(S): Among 121 women who elected single fresh blastocyst transfer (but who could elect to have two frozen blastocysts transferred at once), 79 (65.3%) took home a baby, with a twin pregnancy rate of 7%. Among 285 women who chose two blastocysts for fresh transfer, 184 (64.2%) took home at least one baby, with a twin pregnancy rate of 34% and five perinatal deaths. CONCLUSION(S): With technically appropriate blastocyst culture and freezing, and elective single blastocyst transfer in the fresh cycle, the overall multiple pregnancy rate can be reduced by >75%, permitting in this series a slight increase in the chance of taking home a baby.

Reducing the multiple pregnancy rate in ART.

The greatest risk element in any form of assisted conception, is the risk to a fetus within a multiple pregnancy, even with twin implantation. Recent research has examined the contribution of single embryo transfer in reducing the incidence of multiple gestation within IVF. Two recent studies from our assisted conception centres have demonstrated that single embryo transfer can be undertaken without compromising the patient's ultimate chance of having a successful ongoing pregnancy. The first study was a randomized trial comparing the pregnancy rates in women having two embryos transferred at day two or three after oocyte collection, with that of a second group undergoing single blastocyst transfer. The results revealed an equivalent ongoing pregnancy rate but a significant reduction in the twin rate (to zero) in the single transfer group. A second study examined the cumulative pregnancy rate in women with two or more suitable blastocysts after oocyte collection for transfer, when the final chance of pregnancy was calculated after all embryos had been transferred fresh and in subsequent frozen-thaw embryo transfers. The results were calculated for two groups of women in this data set, one receiving a single embryo for transfer fresh and the second group having two embryos transferred fresh. There was an initial improvement in the fresh embryo transfer group having two transferred (59% vs 44% for the single transfer group), but when additional pregnancies from frozen-thawed pregnancies were added, there was no difference in the final cumulative pregnancy rate in either group (74% for the single transfer group and 70% for the double transfer group). In contrast, 28% of overall pregnancies in the (initial) double transfer group were multiple, whereas only 5% of the (initial) single transfer group were twins. The development of high quality incubation systems within IVF that allow for both blastocyst culture and successful cryopreservation allow for both a high pregnancy rate and the development of strategies to reduce the multiple pregnancy rate.

Experiments towards the synthesis of the ergot alkaloids and related structures. Part 8. The total synthesis of 4-methyl-2,3,4,4a,5,6-hexahydrobenzo[f]quinoline-2-carbonitrile hydrochloride hemihydrate, an immediate precursor of the despyrrole analogues of lysergic acid and its amides.

Exposure of the N-methoxycarbonyl-bicyclic-keto-acid 5 (improved preparation) to the Barnick beta-keto-acid synthesis yielded an aqueous solution of the sodium salts of the beta-keto-acids 26 and 27 which on heating at 60-65 degrees C furnished the N-methoxycarbonyl-tricyclic-ketone 9 (55%) plus the hydroxy-ketone 28 which on acid treatment raised the yield of 9 to 68%. Reduction (NaBH4) of 9 yielded the alcohol 32 (94%) which was treated with thionyl chloride followed by copper (I) cyanide and sodium iodide in acetonitrile to give the tricyclic-N-methoxycarbonyl nitrile 35 whose relative configuration was obtained by X-ray analysis. Attempts to remove the N-methoxycarbonyl group from 35 were unsuccessful. Conversion of the alcohol 32 to its methoxypropyl ether 41 followed by reaction with ethereal MeLi-LiBr yielded the amino-alcohol 39 (75%) converted to the N-formyl-tricyclic alcohol 42 with formic-acetic anhydride (70%). The alcohol 42 was then converted into the N-formyl nitrile 44 via the chloride 43 as employed in the earlier synthesis of the nitrile 35. Removal of the N-formyl group from the nitrile 44 was achieved by refluxing methanolic hydrochloric acid to give the required amino-nitrile hydrochloride 46 (91%) whose structure was confirmed by X-ray analysis. Reaction of the free base with methyl iodide in ethyl acetate in the presence of calcium carbonate furnished the N-methyl base 48 isolated as its hydrochloride, hemihydrate 49 (59%). The overall yield of 49 via this eleven-step synthesis was 3.4%.

Frequency of isolation and antimicrobial susceptibility patterns of Staphylococcus intermedius and Pseudomonas aeruginosa isolates from canine skin and ear samples over a 6-year period (1992-1997).

Staphylococcus intermedius (S. intermedius) was isolated from 88.6% and 49.4% of skin and ear samples, respectively, during the years 1992 through 1997, and frequency of isolation remained unchanged. More than 95% of all S. intermedius isolates were susceptible to cephalothin and oxacillin, providing support for empirical treatment of canine skin and ear infections with cephalexin. Pseudomonas aeruginosa (P. aeruginosa) was isolated from 7.5% and 27.8% of skin and ear samples, respectively. The frequency of isolation from skin samples increased over the study period. Because of multidrug-resistant profiles for P. aeruginosa isolates, especially for ear isolates, empirical treatment of P. aeruginosa infections is not advisable.

Prevalence of serum thyroid hormone autoantibodies in dogs with clinical signs of hypothyroidism.

OBJECTIVE: To determine prevalence of thyroid hormone autoantibodies (THAA) in serum of dogs with clinical signs of hypothyroidism. DESIGN: Cohort study. SAMPLE POPULATION: 287,948 serum samples from dogs with clinical signs consistent with hypothyroidism. PROCEDURE: Serum THAA were detected by use of a radiometric assay. Correlation and chi2 analyses were used to determine whether prevalence varied with breed, age, sex, or body weight. Only breeds for which > or = 50 samples had been submitted were used for analysis of breed prevalence. RESULTS: Thyroid hormone autoantibodies were detected in 18,135 (6.3%) samples. The 10 breeds with the highest prevalence of THAA were the Pointer, English Setter, English Pointer, Skye Terrier, German Wirehaired Pointer, Old English Sheepdog, Boxer, Maltese, Kuvasz, and Petit Basset Griffon Vendeen. Prevalence was significantly correlated with body weight and was highest in dogs between 2 and 4 years old. Females were significantly more likely to have THAA than were males. CONCLUSIONS AND CLINICAL RELEVANCE: Thyroid hormone autoantibodies may falsely increase measured triiodothyronine (T3) and thyroxine (T4) concentrations in dogs; results suggest that T3 concentration may be falsely increased in approximately 57 of 1,000 dogs with hypothyroidism and that T4 concentration may be falsely increased in approximately 17 of 1,000 dogs with hypothyroidism. Results also suggested that dogs of certain breeds were significantly more or less likely to have THAA than were dogs in general.