Development and early outcomes of the national training initiative for transanal total mesorectal excision in the UK

AIM

Transanal total mesorectal excision (TaTME) has attracted substantial interest amongst colorectal surgeons but its technical challenges may underlie the early reports of visceral injuries and oncological concerns. The aim of this study was to report on the feasibility, development and the outcome of the national pilot training initiative for TaTME-UK.

METHODS

TaTME-UK was successfully launched in September 2017 in partnership with the healthcare industry and endorsed by the Association of Coloproctology of Great Britain and Ireland. This multi-modal training curriculum consisted of three phases: (i) set-up; (ii) selection of pilot sites; and (iii) formal proctorship programme. Bespoke Global Assessment Scoring (GAS) forms were designed and completed by both trainees and mentors. Data were collected on patient demographics, tumour characteristics and perioperative clinical and histological outcomes.

RESULTS

Twenty-four proctored cases were performed by 10 colorectal surgeons from five selected pilot sites. Median operative time was 331 ± 90 (195-610) min which was reduced to 283 ± 62 (195-340) min in the final case. Independent performance (GAS score of 5) was achieved for most operative steps by case 5. There was one conversion (4.2%), but no visceral injuries. Pathological data confirmed no bowel perforation and intact quality of the mesorectal TME specimens with clear distal margin in all cases and circumferential margins in 23/24 cases (96%).

CONCLUSION

This exploratory study demonstrates acceptable early outcomes in a small cohort suggesting that a competency-based multi-modal training programme for TaTME can be feasible and safe to implement at a national level.

A comparison of serum metabolic and production profiles of dairy cows that maintained or lost body condition 15 days before calving

Body condition score (BCS) change is an indirect measure of energy balance. Energy balance before calving may affect production and health in the following lactation. It is likely that cows may experience BCS loss before calving due to negative energy balance. The objective of this study was to determine if loss of BCS 15d before calving affected milk production, BCS profile, and metabolic status during the transition period and early lactation. On d -15 to d 0 relative to calving, BCS was assessed (1=emaciated, 5=obese) for 98 Holstein-Friesian cows. The cows were divided into 2groups: those that did not lose BCS between d -15 and d 0 (maintained, BCS-M, n=55) and those that lost BCS from d -15 to d 0 (lost, BCS-L, n=43, average loss of 0.29±0.11 BCS). The fixed effects of BCS group, parity, week (day when analyzing milk production records), their interactions, and a random effect of cow were analyzed using PROC MIXED of SAS (SAS Institute Inc., Cary, NC). Before calving, BCS-L cows tended to have higher concentrations of nonesterified fatty acids than BCS-M cows (0.88 vs. 0.78mmol/L). After calving, BCS-L cows had higher nonesterified fatty acid concentrations in wk 1 (0.93 vs. 0.71mmol/L), wk 2 (0.84 vs. 0.69mmol/L), and wk 4 (0.81 vs. 0.63mmol/L) than BCS-M cows. The BCS-L cows had higher concentrations of β-hydroxybutyrate (BHB) in wk 1 (0.72 vs. 0.57mmol/L), wk 2 (0.97 vs. 0.70mmol/L), and wk 4 (0.94 vs. 0.67mmol/L) compared with BCS-M cows. We detected significant reductions in insulin concentrations in BCS-L cows from wk -1 (2.23 vs. 1.37 µIU/mL) to wk 2 (1.68 vs. 0.89 µIU/mL) and wk 4 (2.21 vs 1.59 µIU/mL) compared with BCS-M cows. Prevalence of subclinical ketosis increased in BCS-L cows in wk 3 and 4 when BHB was ≥1.4mmol/L and in wk 1, 3, and 4 when BHB was ≥1.2mmol/L. In wk 1, BCS-L cows tended to have lower levels of calcium than BCS-M cows (2.33 vs. 2.27mmol/L). We found no differences between the groups of cows for milk yield and energy-corrected milk. The BCS-L cows had lower BCS up to 75d in lactation. Overall, BCS-L cows had higher somatic cell scores with an elevated somatic cell score on d 45, d 60, and d 75. There was an overall tendency for BCS-L cows to have higher fat yield and an overall significant increase in fat percentage. Overall, BCS-L cows had lower lactose percentage, with a reduction on d 60. This work shows that BCS loss before calving may have significant consequences for metabolic status, milk composition, somatic cell score, and BCS profile in dairy cows.

Paradoxical effect of supplementary progesterone between Day 3 and Day 7 on corpus luteum function and conceptus development in cattle

The aim of the present study was to investigate the effect of short-term progesterone (P4) supplementation during the early metoestrous period on circulating P4 concentrations and conceptus development in cattle. The oestrous cycles of cross-bred beef heifers were synchronised using a 7-day P4-releasing intravaginal device (PRID® Delta; 1.55 g P4) treatment with administration of a prostaglandin F2α analogue (Enzaprost; CEVA Sante Animale) the day before PRID® Delta removal. Only those heifers recorded in standing oestrus (Day 0) were used. In Experiment 1, heifers were randomly assigned to one of five groups: (1) control: no treatment; (2) placebo: insertion of a blank device (no P4) from Day 3 to Day 7; (3) insertion of a PRID® Delta from Day 3 to Day 7; (4) insertion of a PRID® Delta from Day 3 to Day 5; or (5) insertion of a PRID® Delta from Day 5 to Day 7. In vitro-produced blastocysts were transferred to each heifer in Groups 2–5 on Day 7 (n = 10 blastocysts per heifer) and conceptuses were recovered when heifers were killed on Day 14. Based on the outcome of Experiment 1, in Experiment 2 heifers were artificially inseminated at oestrus and randomly assigned to one of three treatment groups: (1) placebo; (2) PRID from Day 3 to Day 5; or (3) PRID from Day 3 to Day 7. All heifers were killed on Day 16 and recovered conceptuses were incubated in synthetic oviducal fluid medium for 24 h; spent media and uterine flushes were analysed for interferon-τ (IFNT). In both experiments, daily blood samples were taken to determined serum P4 concentrations. Data were analysed using the PROC MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Insertion of a PRID resulted in an increase (P < 0.05) in serum P4 that declined following removal. In Experiment 1, P4 supplementation from Day 3 to Day 5 (17.0 ± 1.4 mm) or Day 3 to Day 7 (11.3 ± 2.3 mm) increased conceptus length compared with placebo (2.1 ± 1.8 mm). Serum P4 was significantly lower from Day 9 to Day 14 (P < 0.05) and the weight of the Day 14 corpus luteum (CL) was lower in the PRID Day 3–7 group than the placebo or control groups. In Experiment 2, supplementation from Day 3 to Day 5 (94.0 ± 18.8 mm) or Day 3 to Day 7 (143.6 ± 20.6 mm) increased conceptus length on Day 16 compared with placebo (50.3 ± 17.4 mm). Serum P4 was significantly lower in the two supplemented groups following PRID removal compared with placebo (P < 0.05) and was associated with a lower CL weight in the Day 3–7 group. Conceptus length was strongly correlated with the IFNT concentration in the uterine flush (r = 0.58; P = 0.011) and spent culture medium (r = 0.68; P < 0.002). The findings of the present study highlight the somewhat paradoxical effects of P4 supplementation when given in the early metoestrous period in terms of its positive effect on conceptus development and its potentially negative effects on CL lifespan.

Prevalence of Helicobacter pylori infection in children in the Bahamas

OBJECTIVE

Helicobacter pylori (H pylori) is a common bacterial infection that is associated with significant morbidity and mortality worldwide. This bacterium causes a chronic infection that is causally related to illnesses ranging from gastritis, peptic ulcer disease to gastric cancer. It is generally considered that it is acquired in childhood but the prevalence varies considerably between countries and communities. There are few data on the prevalence of H pylori in the Caribbean and none on the prevalence of H pylori in children in the Bahamas. The aim of this pilot study was to determine the prevalence of H pylori infection in a cohort of school children in the Bahamas.

METHODS

One hundred and sixty-one children attending a public primary school in the Bahamas were invited to participate in this study. Consent was obtained for 107 children and each participant completed a brief questionnaire. Valid data were available for 96 of these children. Active H pylori infection was determined using the 13C urea breath test (UBT).

RESULTS

Fifty-two children tested positive for H pylori, yielding a prevalence of 54.2%. The median age in the study was nine years with 46.9% male and 53.1% female. No significant relationship was found between gender breastfeeding, pets and H pylori status.

CONCLUSION

The prevalence reported in this study is the highest reported in asymptomatic children in the Caribbean. Further studies are required to determine risk factors for acquisition of H pylori infection in this population.

Endometrial response of beef heifers on day 7 following insemination to supraphysiological concentrations of progesterone associated with superovulation

Ovarian stimulation is a routine procedure in assisted reproduction to stimulate the growth of multiple follicles in naturally single-ovulating species including cattle and humans. The aim of this study was to analyze the changes induced in the endometrial transcriptome associated with superovulation in cattle and place these observations in the context of our previous data on changes in the endometrial transcriptome associated with elevated progesterone (P4) concentrations within the physiological range and those changes induced in the embryo due to superovulation. Mean serum P4 concentrations were significantly higher from day 4 to day 7 in superovulated compared with unstimulated control heifers (P < 0.05). Between-group analysis revealed a clear separation in the overall transcriptional profile of endometria from unstimulated control heifers (n = 5) compared with superovulated heifers (n = 5). This was reflected in the number of differentially expressed genes (DEGs) identified between the two groups with 795 up- and 440 downregulated in superovulated endometria. Ten times more genes were altered by superovulation (n = 1,234) compared with the number altered due to elevated P4 within physiological ranges by insertion of a P4-releasing intravaginal device (n = 124) with only 22 DEGs common to both models of P4 manipulation. Fewer genes were affected by superovulation in the embryo compared with the endometrium, (443 vs. 1,234 DEGs, respectively), and the manner in which genes were altered was different with 64.5% of genes up- and 35.5% of genes downregulated in the endometrium, compared with the 98.9% of DEGs upregulated in the embryo. In conclusion, superovulation induces significant changes in the transcriptome of the endometrium which are distinct from those in the embryo.

Effect of follicular aspiration just before ovulation on corpus luteum characteristics, circulating progesterone concentrations and uterine receptivity in single-ovulating and superstimulated heifers

The aim of this study was to investigate, in unstimulated and superstimulated heifers, the effect of follicle aspiration just before ovulation on corpus luteum (CL) development, circulating progesterone (P4) concentrations and the ability of the uterus to support embryo development. Following follicle aspiration or ovulation timed from GNRH administration, CL development was assessed by daily ultrasonography, and CL function was assessed in terms of the capacity to produce P4 and the expression of genes involved in steroidogenesis in luteal tissue. The capacity of the uterine environment to support conceptus development was assessed following transfer and recovery of in vitro-produced embryos. Follicular aspiration just before the expected time of ovulation leads to a significant reduction in CL diameter, CL area and area of luteal tissue. This was associated with a decrease in circulating P4 in both unstimulated and superstimulated heifers. Follicle aspiration leads to a reduction in conceptus length and area on day 14 in unstimulated heifers only. Follicle aspiration leads to a reduction in the expression of LHCGR in luteal tissue from unstimulated heifers compared with those in which the CL formed after ovulation. Superstimulation significantly reduced the expression of STAR in luteal tissue in both ovulated and follicle-aspirated heifers. In conclusion, in stimulated and unstimulated heifers, aspiration of the preovulatory dominant follicle(s) just before expected ovulation interferes with the subsequent formation and function of the CL, in terms of size and P4 output and this, in turn, is associated with a reduced capacity of the uterus to support conceptus elongation in unstimulated heifers.

156 EFFECT OF DURATION POSTPARTUM ON OOCYTE QUALITY IN LACTATING HOLSTEIN COWS FOLLOWING TRANSVAGINAL FOLLICLE ASPIRATION AND IN VITRO FERTILIZATION

The objective of this study was to examine the effect of duration postpartum on oocyte quality in lactating dairy cows, as assessed by oocyte morphology and development after fertilization and culture in vitro. Holstein-Friesian spring-calving cows were used (n = 16; parity 3.0 ± 0.36, weight at calving 611 ± 16.2 kg, previous 305-day milk yield 6454.0 ± 276.4 kg). Body weight (BW) and body condition score (BCS) were recorded at approximately 2 weeks before the expected calving date, at calving and then weekly until the end of the experiment (approximately 80 days postpartum). Blood plasma samples were collected weekly, beginning 2 weeks before the expected calving date and continuing until the end of the experiment and were analysed for nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), insulin, insulin-like growth factor I (IGF-I) and glucose. There was a linear decline in BW from calving (Day 0) to Day 28, after which it remained stable. The BCS declined from 14 days precalving, reaching a nadir at approximately Day 35 to 42, after which it increased to the end of the period. Nonesterified fatty acids were significantly elevated from the week before calving until Day 42 postcalving, whereas BHBA was significantly elevated from calving to Day 49. The IGF-I declined dramatically from Day –14 to a nadir on Day 7. There was a significant increase in glucose from Day –7 to Day 0, followed by a precipitous decline to Day 7. Based on the assumption that uterine involution (UI) is complete by approximately Day 42 postpartum in most cows, data from Day 0 to 42 postpartum (pre-UI) were compared with corresponding data from Day 42 to 80 (post-UI). Apart from BCS, all the physiological parameters measured (milk yield, BW and blood metabolites) differed significantly between the 2 periods. In particular, IGF-I, insulin and glucose concentrations were higher after Day 42, whereas BHBA and NEFA were lower compared with before Day 42. The number of oocytes recovered per session and oocyte quality grade did not differ between periods. Positive associations of follicles aspirated and insulin, BHBA and NEFA were detected. Number of oocytes recovered was positively associated with milk yield, BW, glucose and NEFA. Number of cleaved oocytes was positively associated with BW and NEFA. In conclusion, the data do not provide evidence of an effect of lactation-induced metabolic stress on oocyte developmental competence in the postpartum dairy cow assessed in terms of morphological quality and ability to develop after IVF. This work was supported by Science Foundation Ireland (07/SRC/B1156).

85 EFFECT OF FOLLICULAR ASPIRATION JUST PRIOR TO OVULATION ON CORPUS LUTEUM CHARACTERISTICS, CIRCULATING PROGESTERONE CONCENTRATIONS AND UTERINE RECEPTIVITY IN SINGLE-OVULATING BEEF HEIFERS

Progesterone (P4) has a crucial impact on the transcriptome of the uterine endometrium and the preparation of the uterus to support implantation. The aim of this study was to investigate the effect of follicle aspiration just before ovulation on corpus luteum (CL) development, circulating P4 concentrations and the ability of the uterus to support embryo development and conceptus elongation. We tested the hypothesis that the unavoidable loss of follicular fluid and some granulosa cells during aspiration of the preovulatory follicle would compromise the development and function of the developing CL and that this would be associated with reduced P4 and a poorer uterine environment. Oestrous cycles of crossbred beef heifers were synchronized using an 8-day CIDR treatment with administration of a prostaglandin F2α analogue on the day before CIDR removal to ensure CL regression. Heifers were checked for signs of oestrus 4 times per day commencing 30 h after CIDR withdrawal and only those recorded in standing oestrus (Day 0, n = 20) were used. All heifers received a gonadotropin-releasing hormone agonist (0.01 mg buserelin) 48 h after CIDR removal to induce an LH surge. Half of the animals underwent follicle aspiration 20 h later, while the remainder underwent ovulation. Daily transrectal ultrasonography was carried out from Day 3 to 13 to record CL development. Daily blood samples were collected from Day 0 to 14 for circulating P4 concentrations. To test the ability of the uterus to support embryo development and conceptus elongation, Day 7 in vitro-produced blastocysts were transferred to the uteri of synchronised recipients (7 to 10 blastocysts per recipient). All recipients were slaughtered on Day 14 to assess embryo survival and conceptus size. CL diameter and CL area were significantly reduced in the follicle aspirated group compared with controls from Day 6 onwards (P ≤ 0.05). Similarly, at slaughter on Day 14, CL weight (4.17 ± 0.48 vs 7.05 ± 1.65 mm), diameter (19.89 ± 1.35 vs 24.64 ± 2.07 mm) and area (321.94 ± 45.01 vs 510.18 ± 69.41 mm2) were lower in aspirated heifers (P ≤ 0.05). Circulating P4 concentrations were lower at all time points from Day 3 to Day 14 but were only significantly lower from Day 12 onwards (P ≤ 0.05). Conceptus length (2.08 ± 0.29, n = 56 vs 4.55 ± 0.78 mm, n = 45) and area (2.52 ± 0.39 vs 5.61 ± 1.12 mm2) were lower (P ≤ 0.05) in heifers undergoing follicular aspiration compared with those undergoing ovulation. In conclusion, aspiration of the preovulatory dominant follicle just before expected ovulation was associated with a compromised CL in terms of size and P4 output and this, in turn, was associated with a reduced capacity of the uterus to support the initiation of conceptus elongation. Supported by Science Foundation Ireland (07/SRC/B1156).

PHLDA2 is an imprinted gene in cattle

Genomic imprinting is an epigenetic non-Mendelian phenomenon found predominantly in placental mammals. Imprinted genes display differential expression in the offspring depending on whether the gene is maternally or paternally inherited. Currently, some 100 imprinted genes have been reported in mammals, and while some of these genes are imprinted across most mammalian species, others have been shown to be imprinted in only a few species. The PHLDA2 gene that codes for a pleckstrin homology-like domain, family A (member 2), protein has to date been shown to be a maternally expressed imprinted gene in humans, mice and pigs. Genes subject to imprinting can have major effects on mammalian growth, development and disease. For instance, disruption of imprinted genes can lead to aberrant growth syndromes in cloned domestic mammals, and it has been demonstrated that PHLDA2 mRNA expression levels are aberrant in the placenta of somatic clones of cattle. In this study, we demonstrate that PHLDA2 is expressed across a range of cattle foetal tissues and stages and provide the first evidence that PHLDA2 is a monoallelically expressed imprinted gene in cattle foetal tissues, and also in the bovine placenta.

115 EXPRESSION OF RADICAL S-ADENOSYL METHIONINE DOMAIN CONTAINING-2 (RSAD2) AND TRANSFORMING GROWTH FACTOR β (TGF-β) IN BOVINE PERIPHERAL BLOOD MONONUCLEAR CELLS DURING PREGNANCY: IDENTIFICATION OF POTENTIAL BIOMARKERS TO DETERMINE PREGNANCY STATUS

During the bovine peri-implantation period, immune cells are exposed to endocrine and paracrine signals, which support feto-placental development. Recent studies in cattle have shown that the antiviral factor Mx2, known to be up-regulated by conceptus-derived interferon-τ in pregnancy, is detected in peripheral blood mononuclear cells (PBMC) and can be used for pregnancy detection on Day 18. The objectives of the current study were to correlate mRNA expression levels of pregnancy associated factors and immune modulators RSAD2 (radical S-adenosyl methionine domain containing-2) and TGF-β (transforming growth factor β) in circulating PBMCs, with pregnancy status in dairy cows and heifers. Holstein-Friesian heifers (n = 12) and lactating dairy cows (n = 17) were synchronised to estrus and artificially inseminated (bred) or not (non bred, n = 4). Blood samples were collected on Day 0 (day of AI or estrus), 5, 7, 13, 16, 20, and 25 for PBMC isolation. Pregnancy was diagnosed retrospectively by transrectal ultrasonography at Days 30 and 60 after breeding. The relative quantification of RSAD2 and TGF-β transcript abundance, analysed by qPCR, was normalised against PPIA and calculated according to the relative standard curve method. Data from duplicates were pooled, and a mixed model was run on the pooled Cq values for each stage. Genes were considered as differentially expressed if the mixed model P value was <0.05. RSAD2 mRNA abundance was 2-fold higher in pregnant heifers compared with non-bred heifers on Day 20 (P < 0.01) and Day 25 (P < 0.03) post AI. Likewise, RSAD2 mRNA expression was greater (2.25 fold) in pregnant heifers compared with heifers that were inseminated but not pregnant (P < 0.007). In contrast, RSAD2 expression was not significantly different in pregnant cows compared to non-bred or bred but non-pregnant cows. TGF-β mRNA abundance was significantly lower in both pregnant cows (3.5-fold, P < 0.04) and pregnant heifers (4.5-fold, P < 0.01) compared to non-bred animals as early as Day 13. This suppression of expression was maintained until Day 20 in heifers (3.9-fold, P < 0.02). In addition, PBMC TGF-β mRNA expression was lower in pregnant cows compared with bred non-pregnant cows (1.65-fold, P < 0.06). In conclusion, Day 20 PBMC RSAD2 expression may be a useful predictor of pregnancy maintenance in dairy heifers. However, decreased TGF-β expression as early as Day 13 appears to be a more powerful indicator of the presence of a viable embryo in both dairy heifers and cows and may play a role in the establishment and maintenance of pregnancy through the restriction of monocyte recruitment or activation during the time of maternal recognition of pregnancy. Research supported by Science Foundation Ireland (PICA-B813)

Effect of elevated circulating progesterone concentration on bovine blastocyst development and global transcriptome following endoscopic transfer of in vitro produced embryos to the bovine oviduct

Elevated concentrations of circulating progesterone in the immediate postconception period have been associated with an increase in embryonic growth rate, interferon-tau production, and pregnancy rate in cattle and sheep. Much of this effect is likely mediated via downstream effects of progesterone-induced changes in gene expression in the uterine tissues. Using state-of-the-art endoscopic techniques, this study examined the effect of elevated progesterone on the development of in vitro produced bovine zygotes transferred to the oviducts of heifers with high or normal circulating progesterone concentrations and on the transcriptome of blastocysts developing under such conditions. Simmental heifers (n = 34) were synchronized using a controlled internal drug release (CIDR) device for 8 days, with a prostaglandin F(2 alpha) analogue administered 3 days before removal of the CIDR device. Only animals exhibiting a clear standing estrus (Day 0) were used. To produce animals with divergent progesterone concentrations, half of the animals received a progesterone-releasing intravaginal device (PRID) on Day 3 of the estrous cycle; the PRID was left in place until embryo recovery. All animals were sampled for blood daily from Day 0 to Day 7. Cleaved embryos were transferred by endoscopy to the ipsilateral oviduct of each recipient on Day 2 and then recovered by nonsurgically flushing the oviduct and the uterus on Day 7. The number of embryos developing to the blastocyst stage was recorded at recovery and following overnight culture in vitro. Potential effects of elevated progesterone on transcript abundance were examined using the Affymetrix GeneChip Bovine Genome Array. Insertion of a PRID on Day 3 resulted in a significant elevation of progesterone concentration (P < 0.05) from Day 3.5 until Day 6. Elevated progesterone did not affect the proportion of embryos developing to the blastocyst stage. Genomewide gene expression analysis identified 194 differentially expressed genes between embryos collected from heifers with normal or elevated progesterone, and quantitative real-time PCR validation with a subset of selected genes and an independent sample confirmed the microarray results. Interaction network analysis indicated a significant interaction between progesterone-regulated genes in the blastocyst and in the maternal endometrium. These results suggest that elevated concentrations of progesterone do not affect the ability of the early embryo to reach the blastocyst stage in vivo but do result in subtle changes to the transcriptome of the embryo that may be associated with advanced elongation posthatching.

Characterisation of endometrial gene expression and metabolic parameters in beef heifers yielding viable or non-viable embryos on Day 7 after insemination

The aim of the present study was to compare the hormonal and metabolic characteristics and endometrial gene expression profiles in beef heifers yielding either a viable or degenerate embryo on Day 7 after insemination as a means to explain differences in embryo survival. Oestrus was synchronised in cross-bred beef heifers (n = 145) using a controlled internal drug release (CIDR)–prostaglandin protocol. Heifers (n = 102) detected in standing oestrus (within 24–48 h after CIDR removal) were inseminated 12–18 h after detection of oestrus (Day 0) with frozen–thawed semen from a single ejaculate of a bull with proven fertility. Blood samples were collected from Day 4 to Day 7 after oestrus to measure progesterone (on Days 4, 5 and 7), insulin and insulin-like growth factor (IGF)-I (on Days 4 and 6) and urea (on Day 7) concentrations. All animals were killed on Day 7. Uterine pH was determined at the time of death. Animals from which an embryo was recovered were classified as either having a viable embryo (morula/blastocyst stage; n = 32) or a retarded embryo (arrested at the two- to 16-cell stage; n = 19). In addition, 14 single-celled unfertilised oocytes were recovered, giving an overall recovery rate of 64%. There was no significant difference in the blood parameters determined or uterine pH at the time of death between heifers with either a viable or retarded embryo. The relative abundance of nine transcripts (i.e. MOGAT1, PFKB2, LYZ2, SVS8, UHRF1, PTGES, AGPAT4, DGKA and HGPD) of 53 tested in the endometrial tissue differed between heifers with a viable or retarded embryo. Both LYZ2 and UHRF1 are associated with regulation of the immune system; PFKFB2 is a mediator in glycolysis; MOGAT, AGPAT4 and DGKA belong to the triglyceride synthesis pathway; and PTGES and HGPD belong to the prostaglandin pathway. Both these metabolic pathways are important for early embryonic development. In conclusion, retarded embryo development in the present study was not related to serum progesterone, IGF-I, insulin or urea concentrations, nor to uterine pH at the time of death. However, altered expression of genes involved in the prostaglandin and triglyceride pathways, as well as two genes that are closely associated with the regulation of immunity, in the endometrium may indicate a uterine component in the retardation of embryo development in these beef heifers.

Effect of embryo source and recipient progesterone environment on embryo development in cattle

The aim of the present study was to examine the effect of embryo source (in vivo v. in vitro) and the progesterone environment into which it was transferred on Day 7 on embryo survival and size on Day 13. Day 7 blastocysts were produced either in vivo using superovulation, artificial insemination and non-surgical embryo recovery or in vitro using in vitro maturation, fertilisation and culture. In order to produce animals with divergent progesterone concentrations, following synchronisation recipients were either superovulated (High progesterone; n = 10) or not (Control progesterone; n = 10). Ten blastocysts, produced either in vivo or in vitro, were transferred to each recipient on Day 7. Both groups were killed on Day 13. The mean progesterone concentration from Day 7 to Day 13 (the period when the embryos were in the uterus) in the High and Control progesterone recipients was 36.32 +/- 1.28 and 10.30 +/- 0.51 ng mL(-1), respectively. Of the in vivo embryos transferred, the overall recovery rate at Day 13 was 64%, which was higher (P < 0.001) than that of 20% for the in vitro embryos transferred. The mean area of embryos recovered from High progesterone recipients was 3.86 +/- 0.45 mm(2) (n = 28) compared with 1.66 +/- 0.38 mm(2) (n = 24) for embryos recovered from Control progesterone recipients (P < 0.001). Similarly, the origin of the embryo used for transfer affected embryo size on Day 13. In summary, the recovery rate of blastocysts was higher for in vivo- than in vitro-derived embryos. Blastocyst size was approximately 2.3-fold greater in recipients with high compared with normal progesterone. The present study lends strong support to the hypothesis that an earlier rise in progesterone after conception stimulates blastocyst growth and the development of competent embryos.

Effect of increasing progesterone concentration from Day 3 of pregnancy on subsequent embryo survival and development in beef heifers

Higher systemic progesterone in the immediate post-conception period is associated with an increase in embryonic growth rate, interferon-tau production and pregnancy rate in cattle. The objective of this study was to examine the effect of increasing progesterone concentration on Day 3 on subsequent embryo survival and development. Oestrus (Day 0) was synchronised in beef-cross heifers (n = 210) and approximately two-thirds of the heifers were inseminated with semen from a proven sire, while the remainder were not inseminated. In order to produce animals with divergent progesterone concentrations, half of the animals received a progesterone-releasing intravaginal device (PRID) on Day 3 of the oestrous cycle, which was left in situ until slaughter. The four treatment groups were: (i) pregnant, high progesterone; (ii) pregnant, normal progesterone; (iii) non-pregnant, high progesterone; and (iv) non-pregnant, normal progesterone. Animals were blood-sampled twice daily from Days 0 to 8 and once daily thereafter until slaughter on Days 5, 7, 13 or 16, corresponding to the 16-cell stage, the blastocyst stage, the beginning of elongation and the day of maternal recognition of pregnancy, respectively. Embryos were recovered by flushing the tract with phosphate-buffered saline and characterised by stage of development and, in the case of Days 13 and 16, measured. Data were analysed by mixed models ANOVA, Chi-square analysis and Student’s t-test where appropriate. Insertion of a PRID on Day 3 increased (P < 0.05) progesterone concentrations from Day 3.5 onwards. There was no difference between treatments in the proportion of embryos at the expected stage of development on Days 5 or 7 (P > 0.05). While not significantly different, the proportion of viable embryos recovered was numerically greater in the high progesterone group on both Day 13 (58 v. 43%) and Day 16 (90 v. 50%). Elevation of progesterone significantly increased embryonic length on Day 13 (2.24 ± 0.51 mm v. 1.15 ± 0.16 mm, P = 0.034) and Day 16 (14.06 ± 1.18 cm v. 5.97 ± 1.18 cm, P = 0.012). In conclusion, insertion of a PRID on Day 3 of the oestrous cycle increased serum progesterone concentrations on subsequent days, which, while having no phenotypic effect on embryonic development on Days 5 or 7, was associated with an increase in embryonic size on Days 13 and 16.

134 EFFECT OF ELEVATED CIRCULATING PROGESTERONE CONCENTRATION ON DEVELOPMENT OF IN VITRO PRODUCED BOVINE ZYGOTES IN VIVO

Elevated concentrations of circulating progesterone in the immediate post-conception period have been associated with an increase in embryonic growth rate, interferon-tau production, and pregnancy rate in cattle and sheep. Much of this effect is likely mediated via downstream effects of progesterone-induced changes in gene expression in the tissues of the uterus. However, whether or not progesterone has a direct effect on the embryo also is unknown and, at least in vivo, in single ovulating animals, is difficult to assess. Using state-of-the-art endoscopic techniques, the objective of this study was to examine the effect of elevated progesterone on the development of IVP zygotes transferred to the oviducts of cattle with high or normal circulating progesterone concentrations. Simmental heifers (n = 14) were synchronized using a combination of 2 injections of a prostaglandin F2α analogue administered 11 days apart and gonadotropin-releasing hormone. Only animals exhibiting a clear standing oestrus (= day 0) were used. In order to produce animals with divergent progesterone concentrations, half of the animals received a PRID on day 3 of the oestrous cycle, which was left in place until embryo recovery. All animals were blood sampled daily from days 0 to 7. Cleaved embryos were transferred using endoscopy to the ipsilateral oviduct of each recipient on day 2 and recovered by non-surgically flushing the oviduct and the uterus on day 7. The number of embryos developing to the morula/blastocyst stage was recorded at recovery and following overnight culture in CR1aa medium. Data were analyzed by chi-square analysis. Insertion of a PRID on day 3 resulted in a significant elevation in progesterone concentrations from day 4 (2.36 ± 0.16 ng mL–1 v. 0.54 ± 0.10 ng mL–1, P < 0.001) until day 6 (1.98 ± 0.22 ng mL–1 v. 0.95 ± 0.17 ng mL–1; P < 0.01). The recovery rate was lower in animals that received a PRID (P < 0.05). However, there was no effect of progesterone on the proportion of embryos developing to the morula/blastocyst stage. These results suggest that elevated concentrations of progesterone do not affect the ability of the early embryo to reach the blastocyst stage in vivo and that the reported positive effect of high progesterone levels in terms of fertility are manifested after day 8. Table 1. Effect of elevated progesterone concentration on development of in vitro produced bovine zygotes in vivo

Extent of innate dexterity and ambidexterity across handedness and gender: Implications for training in laparoscopic surgery

BACKGROUND

As innate dexterity is considered one of the important predictors of eventual operative competence, an experimental human factors study was conducted to determine innate dexterity and ambidexterity across handedness and gender.

METHODS

50 medical students (right-handed males, left-handed males, and right-handed females) were recruited as participants in a study designed to assess innate dexterity and degree of ambidexterity for endoscopic manipulations in a validated virtual-reality simulator. All participants performed unilateral and bilateral tasks with both dominant and nondominant hands in random sequence. The outcome measures were execution time, extent of ambidexterity (ambidexterity index), aiming errors, and maximum tissue damage.

RESULTS

Right-handed males exhibited a greater level of ambidexterity than left-handed males (p = 0.02 for path length, p = 0.001 for angular path) and right-handed females (p = 0.01 for path length, p = 0.02 for angular path), and more-efficient task performance as measured by execution time (p = 0.001 for males and p = 0.03 across gender). The task quality when executed by the dominant hand was best in right-handed males (p = 0.001 vs. left-dominant males and p = 0.03 across gender). No significant difference was observed in terms of precision control and fine movements (aiming errors and maximum tissue damage) between the three groups.

CONCLUSIONS

These findings indicate that training surgical curricula in laparoscopic surgery should be more flexible to accommodate the innate differences across handedness and gender.

Global gene expression analysis during bovine oocyte in vitro maturation

It is well known that factors such as nutrition, hormonal alterations and environmental compounds can have a profound effect on oocyte quality and subsequently embryo development. Global mRNA expression analysis of immature and mature bovine oocytes was carried out to identify key pathways associated with oocyte meiotic maturation and developmental potential. We have carried out a global mRNA gene expression analysis of bovine oocytes pre- and post-resumption of meiotic maturation using the Affymetrix GeneChip Bovine Genome Array. Approximately 54% of the probe sets representing 23,000 transcripts were detected in bovine oocytes. Of which, 821 transcripts were differentially expressed (>or=2-fold) between the two groups (p<0.05), corresponding to 209 upregulated and 612 down regulated transcripts in the in vitro matured oocytes compared to their immature counterparts. In addition, transcripts uniquely detected in germinal vesicle stage or metaphase II were identified. The gene expression data was classified according to gene ontology; in terms of biological processing, the majority of these genes were associated with regulation activities, including the regulation of: MAPK activity, translation initiation and transcription. Our findings are in agreement with similar data from both mouse and human oocytes. Taken together this data provides a molecular transcriptome blueprint of immature and mature mammalian oocytes. This resource will be invaluable to our long-term objective which is to target identified pathways to elucidate the sensitivity of key regulatory genes and checkpoints of oocyte maturation to internal and external environmental influences.

263 GENE EXPRESSION PROFILING OF IMMATURE AND IN VITRO-MATURED BOVINE OOCYTES USING AFFYMETRIX GENECHIP TECHNOLOGY

Previous studies by our group have demonstrated that oocyte maturation is a crucial event in the determination of subsequent developmental competence. The objective of the current study was to characterize changes in gene expression profiles of bovine oocytes during meiotic maturation. To this end, 5 replicate pools of 200 bovine cumulus–oocyte complexes (COCs)were collected from the ovaries of slaughtered heifers. Upon recovery, 100 COCs from each replicatewere immediately denuded, and the oocytes were snap frozen in liquid nitrogen. The remaining 100 COCs were matured in vitro in TCM-199 supplemented with 10% (v/v) fetal calf serum and 10 ngmL-1 epidermal growth factor for 24 h at 39�C under an atmosphere of 5% CO2 in air with maximum humidity. Following maturation, the remaining COCs were denuded and snap frozen. Total RNA was isolated (mean total RNA content 106.08�38.87 ng per 100 oocytes) and subjected to 2 rounds of amplification incorporating biotin-labeled nucleotides during the second in vitro transcription reaction (mean total RNA content 155.15�51.14 �g per 100 oocytes post-amplification). The resulting labeled antisense RNA was hybridized to a GeneChip Bovine Genome Arrays (Affymetrix, Inc., Santa Clara, CA, USA) (10 chips, 5 replicates each of immature and mature oocytes, n=100 oocytes/chip). Expression data were analysed using Genespring software (Agilent Technologies, Palo Alto, CA, USA), and data were normalized to the median. Overall, 54.9�1.3% and 53.3�3.3% of the 24 178 probe sets representing 23 000 transcripts spotted on the arrays were expressed in immature and in vitro-matured oocytes, respectively. Across the 5 array comparisons, 52 genes were consistently exclusively present in immature oocytes, whereas 16 genes were exclusively present in mature oocytes. A further 821 genes were found to be differentially expressed (≥2-fold) between the 2 groups (P &lt;0.05), of which 209 were up-regulated and 612 were down-regulated in the in vitro-matured oocytes compared with their immature counterparts. The differentially expressed transcripts were classified according to their gene ontology (http://benzer.ubic.ca/ermineJ). The existing Affymetrix annotation was updated by blasting the sequences against bovine, human, and murine databases (≥90% homology; increasing molecular function annotation from 14% to 42%). In terms of olecular function, the majority of these genes were associated with protein or nucleic acid binding (&gt;42%), catalytic activity (24%), signal transduction (7%), transporter activity (5%), and structural molecule activity (5%). In conclusion, we have stablished the molecular transcriptome blueprint of immature and in vitro-matured bovine oocytes. Through comparisons with in vivo-matured oocytes, this resource will be invaluable in determining genes that are involved in controlling the developmental competence of oocytes. This research was funded by the Science Foundation Ireland (02/IN1/B78).

Competence Assessment of Laparoscopic Operative and Cognitive Skills: Objective Structured Clinical Examination (OSCE) or Observational Clinical Human Reliability Assessment (OCHRA)

BACKGROUND

There is no agreed system that is acknowledged as the ideal assessment of laparoscopic operative and cognitive skills. A new approach that combines Objective Structured Clinical Examination (OSCE) and Observational Clinical Human Reliability Assessment (OCHRA) was developed and used to assess trainees' operative and cognitive skills during laparoscopic training courses.

METHODS

Performance of 60 trainees participating in 3-day essential laparoscopic skills training (cognitive and psychomotor) courses were assessed and scored using both OSCE and OCHRA.

RESULTS

The study showed significant inverse correlations between the number of technical errors identified by OCHRA and the scores obtained by OSCE for individual tasks performed either by electro-surgical hook or laparoscopic scissors (r = -0.864 and r = -0.808, respectively). Significant differences between trainees were observed in relation to both overall OSCE scores and OCHRA parameters: execution time, total errors, and consequential errors (P < 0.001).

CONCLUSIONS

OCHRA provides a discriminative feedback assessment of laparoscopic operative skills. OCHRA and OSCE are best regarded as complementary assessment tools for operative and cognitive skills. The present study has documented significant variance between surgical trainees in the acquisition of both cognitive and operative skills.

Clinical presentation of acute chest syndrome in sickle cell disease

In this study the records of 45 patients with sickle cell disease involved in 63 presentations of acute chest syndrome at the Princess Margaret Hospital in Nassau, the Bahamas, between 1997 and 2001 were examined. Patients were divided into three groups on the basis of age (<13 years, 13-18 years, >/=19 years) with a view to assessing clinical presentation. The incidence of symptoms, physical signs, and laboratory findings were enumerated and significant differences between age groups determined. The data were analysed using analysis of variance, t test, and chi(2) test and compared with existing knowledge on the subject. This study proposed to evaluate the clinical presentation of acute chest syndrome with emphasis on historical and physical findings, and to encourage the physician to maintain a high index of suspicion for the condition in susceptible patients. It was found that presentation varied significantly with age groups, children presenting most classically with fever and cough and adults, with chest pain. The 13-18 age group emerged as the group which presented most frequently with the typical symptoms of chest infection, thus potentially making diagnosis easier. Of note, the most frequent finding was a normal examination, while the second commonest physical finding was crepitations on auscultation of the chest.

What kind of patients and physicians value direct-to-consumer advertising of prescription drugs

Direct-to-consumer (DTC) advertising of prescription drugs can enhance the physician-patient relationship, as well as benefiting its sponsor. However, overall benefits can only occur if the patients value the information enough to discuss it with their physicians and the physicians are not predisposed against the DTC information. We investigate the impact of demographics and exposure to marketing on consumers' and physicians' receptiveness to DTC advertising of prescription drugs, using data from two nationwide surveys. We find that consumers who have an ongoing need for health care, that is, those with children or with a chronic condition requiring medication, value prescription drug advertising more highly, while older consumers, consumers who have been sick recently, or more educated consumers are more likely to trust their physicians instead. We find that more experienced physicians, physicians who see more patients, or those who have more exposure to pharmaceutical advertisements are more accepting of DTC advertising of prescription drugs.

Socio-demographic variations in perspectives on cardiovascular disease and associated risk factors

Coronary heart disease (CHD) rates in Ireland are very high but little is known about attitudes to the disease. Qualitative attitudinal data were collected in focus group settings from 74 individuals across socio-demographic categories in order to assess knowledge of and attitudes to CHD and associated risk factors. Focus group questions were derived from group deconstruction of constructs from the Health Belief Model, Theory of Planned Behaviour, Protection Motivation Theory and Social Learning Theory. Participants were drawn from the personnel lists of local government and a health authority hospital. Eight types of groups were constructed according to the various permutations of the three variables: age, gender and occupational group. Analyses revealed good knowledge levels about risk factors among participants. However, participants exhibited mixed loci of control and low motivation to change behaviours. Men generally were less motivated to change than women; older men thought it too late and younger ones too soon. Though white and blue collar groups' views were similar, the discussion in white collar groups was more varied. Participants were sceptical about apparently contradictory medical advice which undermined motivation to change. The data complement earlier work and suggest preventative initiatives should be more focused.

Prostate cancer screening in primary care

BACKGROUND

Little is known about the actual frequency with which men have prostate screening in primary care settings, nor are the determinants of screening understood.

METHODS

We examined the records of 50 consecutive primary care office visits by men aged 50 or older. Men were asked to complete a brief questionnaire outlining their previous use of prostate screening services and the factors that influenced screening.

RESULTS

Screening in the previous year with digital rectal examination (DRE) and prostate specific antigen (PSA) was reported by 46% and 30% of respondents, respectively. Most respondents (86%) had heard of prostate screening and most (78%) believed it was effective. The only factor predictive of screening with DRE in multivariate analysis was a doctor's discussion of screening (odds ratio, 4.8). Two factors were predictive of PSA screening--knowing someone who had prostate cancer (odds ratio, 12.8) and advancing age (odds ratio [per year], 1.1).

CONCLUSIONS

Many men are not having annual prostate screening. Men who were older, who reported knowing someone with prostate cancer, and whose doctors discussed screening, were more likely to have been screened in the past year.

Clamping the small intestine during surgery: predicted and measured sealing forces

During bowel surgery it is often necessary to occlude the bowel using clamps. Occlusion occurs in two stages: approximation of bowel internal surfaces followed by sealing which is necessary to prevent seepage. The occlusive force at both stages depends on the luminal pressure, the latter stage requiring greater force than the former. The difference in luminal pressure across the sealing line results in a slipping force which is resisted by friction between the bowel and the clamp jaw surfaces. A theoretical model was developed to describe these forces and the predicted values obtained from this model were compared with direct measurements carried out on porcine bowel samples in a test rig. It was found that the measured approximation force was between 25 and 50 per cent of the maximum theoretical values and that sealing without seepage requires a clamp force of about ten times the approximation force. Using these results and known intraluminal pressures in the human gastrointestinal tract, a bowel clamp must apply around 7 N to prevent seepage and the coefficient of friction between clamp and bowel should be between 0.6 and 0.9.

Subspecialization manpower in obstetrics and gynecology

Growing interest in the emergence of subspecialties within obstetrics and gynecology prompted a survey of all Junior Fellows of the ACOG. That survey, representing the attitudes and expectations of 1702 housestaff and practitioners, disclosed that nearly 31% of obstetric-gynecologic residents planned to subspecialize as contrasted to 19.5% of postresidency obstetrician-gynecologists who either engaged in or plan to engage in subspecialty training/practice. The highest demand areas seemed to be in endocrinology and perinatology, and most subspecialists either limit or plan to limit their practice to the area specified. There was, in addition, a general feeling that subspecialists should confine their activities to major medical centers, and an unfavorable attitude was expressed toward subspecialty-board-imposed practice restrictions. Details regarding the factors influencing Junior Fellows' response to subspecialization are discussed.

Cost of management of patients with haemophilia

The cost of managing 114 adult haemophiliacs in the west of Scotland was assessed for the period 1 March 1971 to 28 February 1974. Altogether 23 of them (20%) accounted for 80% of the resources used. The cost of hospital treatment of these patients during the period was compared with the predicted cost of home treatment, given the availability of freeze-dried factor VIII concentrate in sufficient amounts. We calculate that adequate on-demand home treatment would cost only 16% more than the present treatment, which is substantially less efficient.

Screening for spina bifida cystica. A cost-benefit analysis

The costs and economic benefits are examined of introducing a programme for the mass-screening of pregnancies for the detection and abortion of fetuses with spina bifida cystica. A benefit-cost index is derived, and the possible effects on it of making different input assumptions are discussed. It is considered that, on economic grounds, screening may be worthwhile only in populations in which the incidence of spina bifida is high.