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Chromosomal analysis of a failed pregnancy following the diagnosis of recurrent miscarriage is not standard practice yet an abnormal karyotype is one of the commonest causes. Array comparative genomic hybridization heralds a new and improved era of cytogenetics, which may prevent unnecessary interventions for patients.

Background: Although women with antiphospholipid antibodies (APLAs) are at increased risk of recurrent miscarriage, the outcome of a subsequent pregnancy is not clearly elucidated. Objectives:To assess the pregnancy outcome of a subsequent pregnancy in women with APLAs and compare this outcome with women with unexplained recurrent miscarriage. Methods: We performed a cohort study among all women who attended the Miscarriage Clinic at Liverpool Women’s Hospital between 1987 and 2006 after being referred due to recurrent miscarriage (≥ 2 consecutive pregnancy losses). All women underwent a standardized investigation sequence. Women with other reasons for recurrent miscarriage were excluded. Results: A total of 693 women fulfilled the selection criteria, of whom 176 (25%) had APLAs. One hundred and twenty‐two (69%) women with APLAs had a subsequent live birth compared with 324 (63%) women with unexplained recurrent miscarriage (OR 1.3, 95% CI 0.9–1.9). No differences were found for birth weight, gestational age, and intra‐uterine growth restriction. When treatment was analyzed, 53/67 (79%) of women with APLAs who had received aspirin and heparin during their pregnancy had a live birth, compared with 64/104 (62%) of women with APLAs who received aspirin only (adjusted OR 2.7, 95% CI 1.3–5.8). In unexplained recurrent miscarriage, stratification for treatment showed no differences in outcome. Conclusion:The prognosis of a subsequent pregnancy in women with APLAs is good. Although this was not a randomized clinical trial, combined treatment of aspirin and heparin seemed associated with a better outcome in women with APLAs, but not in women with unexplained recurrent miscarriage.

To determine whether the effect of oxytocin (OT) on progesterone production in primate luteal tissue may be receptor-mediated, we used biochemical procedures to examine the CL of the baboon (Papio anubis) for the presence of OT receptors (OT-R). CL (n = 5) were obtained by luteectomy from the early (LH + 1−5 days), mid- (LH + 6−10 days), and late (LH + 10−15 days) luteal phases. Biopsies from the uterine fundus were also obtained at the same time. Total receptors were measured by incubating the membrane fractions (120,000 × g fraction) with increasing concentrations of [3H]oxytocin (0.08−1.6 nM) for 30 min at 22 ° C with a protein concentration of 200 μ per tube. Nonspecific binding was evaluated by the addition of excess nonradioactive OT. The receptor-bound tritiated ligand was separated from the nonreceptor-bound ligand through use of polyethylene glycol. For the midluteal phase CL, the affinity Kdwas 1.70 ± 0.03 nmol/L and the mean receptor number (RT) was 122.6 ± 8.3 fmol/mg protein. In comparison, myometrial tissue examined at the same phase of the cycle had a Kdof 1.3 ± 0.1 nmol/L and an RT of 205.0 ± 49.7 fmol/mg protein. Receptors were not detectable in the late luteal phase CL and were significantly lower in the early luteal phase CL (50.7 ± 6.9 fmol/mg protein), with no difference in the Kdvalue. Competitive studies with structurally related and nonrelated peptides indicated the presence of specific receptors for OT in baboon CL.The presence of receptors in the tissue suggests that the effect of OT on CL progesterone production is probably receptor-mediated.

The identification of the cell junction-forming proteins connexin-43, a gap junction protein and E-cadherin, which is a component of adherent junctions, in the corpus luteum of both humans and baboons suggests that cell-cell interactions and metabolic cooperation must occur in this tissue. Occluding junctions are a third type of junction which form a physical barrier between cells. Thus, our aims in this study were firstly to examine the presence of the tight junction-associated protein zonula occludens-1 (ZO-1) by immunohistochemistry, and secondly to determine the concentrations of this protein in the early-, mid- and late luteal phase baboon corpora lutea of the menstrual cycle by a Western analysis. ZO-1 was localized mainly at the periphery of the luteal cells, and the intensity of immunoreactivity varied through the luteal phase, with comparatively stronger immunoreactivity in the mid-luteal phase than the early and late luteal phases. Atretic corpora lutea were devoid of activity. By Western analysis, bands of immunoreactivity were observed at 225 kDa, further confirming the presence of the protein. Maximum activity, as determined by densitometry, was observed in the mid-luteal phase. These data infer the presence of tight junctions in the corpus luteum and suggest that expression of the ZO-1 protein forming these junctions may be hormonally regulated within this tissue.

The effect of Escherichia coli enterotoxin STa on the primary and secondary immune response in F1 (CBA × C57 B1/10) mice immunized against sheep red blood cells (SRBC) was investigated. Modulating action on the IgM and IgG response was found to be dependent on the dose-time administration of the toxin. Immunosuppression of the primary response on the 4th day after immunization was observed when the toxin was injected 15 min before the SRBC, followed by immunostimulation on the 6th day after antigen (Ag) injection. Moreover, toxin administration 48 h before SRBC caused immunosuppression of the primary immune response on the 4th and 6th days. On the other hand, the IgM and IgG secondary immune response, determined 6 days after boosting, was greatly enhanced by toxin administration 15 min before priming (day 0) or boosting (day 26) and 48 h before priming. The same response was suppressed by toxin administration 48 h before booster antigen injection.

We have demonstrated the presence of epidermal growth factor (EGF) and its receptors in human non-gestational corpora lutea. To determine further the characteristics of EGF receptor binding, we examined 30 human corpora lutea throughout the luteal phase and during pregnancy. Scatchard plots of EGF binding in 29 of the 30 corpora lutea were curvilinear, suggesting negative co-operativity. The mean +/- SE of the association constant Ka was (0.9 +/- 0.2) x 10(9) l/mol, the dissociation constant Kd was (2.2 +/- 0.3) x 10(-9) mol/l and the number of binding sites (Rt) was (15.8 +/- 2.1) x 10(-19) mol/micrograms protein for non-gestational corpora lutea. The Kd increased significantly in late pregnancies compared to early pregnancies (P = < 0.005), while Rt was significantly higher in term pregnancies than in either early pregnancy (P < 0.01) or the menstrual cycle (P < 0.001). Corpora lutea atretica (n = 2) and ovarian stroma (n = 6) did not show any EGF binding activity. Our findings demonstrate the presence of specific EGF receptors in human corpora lutea of both the menstrual cycle and pregnancy. The changes in EGF binding parameters in early pregnancy suggest that there may be a relationship between the role of EGF and ovarian steroidogenesis.

Oxytocin has been identified in both non-human primate and human corpora lutea of the menstrual cycle by RIA, immunocytochemistry and HPLC. Evidence for the transcription of the oxytocin gene in this tissue using PCR is available. Oxytocin receptors have been characterized by biochemical procedures. However, there is some debate as to whether the oxytocin identified in these tissues is biologically active and has a role in luteal function. In this study we have demonstrated that oxytocin isolated by gel chromatography of tissue extracts from the baboon and the human corpus luteum is biologically active as determined in a rat uterine bioassay. Since both oxytocin and its receptors are present in these tissues, it is suggested that oxytocin in the human and non-human primate corpora lutea has a functional role.Journal of Endocrinology(1995) 147,525–532

In spite of the importance of the corpus luteum in human reproduction, little is known about its formation after ovulation and during regression in the absence of conception. This is largely due to constraints on the availability of normal human tissue; therefore an appropriate model which could be studied and could provide information applicable to the human was sought. The baboon (Papio), a non-human primate, has been determined to be one such model. Thus, in the past several years our studies have examined the role of luteal peptides in corpus luteum function, and, when possible, we have attempted to examine corpora lutea from the human and baboon in parallel. Although a milk-ejection factor was recognized to be present in luteal tissue in 1910 (Ott and Scott, Proc. Soc. Exp. Biol. Med., Vol. 8, p. 49), the role of oxytocin in luteal physiology has not been easy to ascertain. This is in part due to the methodologies employed to assess its role. Our studies summarized below suggest that oxytocin does not directly affect luteal steroidogenesis but that it may play a role in cell to cell communication involving the expression of the gap junction proteins, the connexins. In view of the fact that oxytocin, its receptor, gap junctions and associated proteins are not unique to the human and non-human primates, the model of luteal development and demise proposed may be applicable to most species.

Cattle feed sources were studied at village level in Pabna district, Bangladesh. A large quantity of feed was offered. In the monsoon the average amount of DM fed to a mature animal of 210kg was 7·1kg d−1, consisting of about equal amounts of straw, weeds and leaves. In winter animals grazed for an average of 3·7hd−1 and were supplemented with 3·9kgDMd−1 (two-thirds straw). In summer they were offered 5·4kgDMd−1 (one-third straw and two-thirds weeds and leaves) and they grazed for 0·5hd−1. The major limiting constraint on cattle production is the quality of the feed offered, particularly in the monsoon period when animals cannot graze. In future, feed quality will become even more of a problem because grazing lands are gradually disappearing.

In Pabna district, Bangladesh there are two cattle production systems: a draught-oriented system with local Deshi cattle and more milk-oriented production with Pabna Milking Cow (PMC) stock.