In vitro produced (IVP) bovine embryos are useful for investigating the mechanisms affecting early embryonic failure. The work in this thesis explored how interleukin-6 (IL6), an embryokine that increases inner cell mass (ICM) influences post-transfer embryonic survival and development of the embryo-proper and fetus. Four replicates of slaughterhouse-derived cumulus oocyte complexes underwent in vitro maturation and fertilization. On day 5 post-fertilization, embryos were treated with either 1% Bovine Serum Albumin (BSA) (CONT) or 100ng/mL recombinant bovine IL6 with 1% BSA (TRT). On day 7.5 post-fertilization, individual blastocysts were loaded into transfer straws. Beef and dairy cow recipients were synchronized with the day of in vitro fertilization using a 7-d CO-Synch protocol. A subset of cows from each group underwent fixed-time artificial insemination (AI) (n=37). The remaining cows underwent embryo transfer (ET) in the uterine horn ipsilateral to a corpus luteum (CL) (IL6 n=35; CONT n=51). Embryo and fetal measurements were performed via transrectal ultrasonography weekly from days 28-56 post-insemination, respectively. Overall pregnancy rates were 40.0% IL6; 19.6% CONT; and 32.4% AI. Crown-rump lengths (CRL) were reduced (P<0.05) in CONT pregnancies when compared with IL6 and AI at days 28, 35, 42, and 56. A tendency (P=0.057) for larger abdominal diameters was detected between IL6 and CONT groups. Also, IL6 had larger crown-nose lengths than CONT (P<0.05) and tended to be larger than AI (P=0.07). In summary, IL6 treatment produced pregnancies resembling AI-generated pregnancies more so than conventionally cultured embryos, supporting the hypothesis that IL6 improves developmental competency of IVP embryos. / Master of Science / The incidences of pregnancy loss in both beef and dairy cattle industries are profound and are upwards of 60 percent. Financial stability for both of these industries revolves closely around the ability of cattle to give birth to a live calf annually. While artificial insemination (AI) has been heavily adopted and utilized widely in the dairy industry, the use of in vitro produced (IVP) bovine embryos has shown promise in lessening some of the stresses placed on impregnating cattle. The IVP of bovine embryos serves as a strong model to understand how pregnancy losses occur. Briefly, IVP involves the collection of eggs from donor animals, and subsequent fertilization to mimic what occurs within the animal naturally. A disadvantage of in vitro produced embryos is their reduced likelihood to establish pregnancy after transfer into recipient animals. Interleukin-6 (IL6) was recently identified as a pro-developmental factor that may improve the quality and post-transfer competency of in vitro produced embryos. The objective of this work was to determine if IL6 supplementation during in vitro culture improves post-transfer fetal development. Oocytes (i.e. eggs) were retrieved from slaughterhouse-derived ovaries and subjected to in vitro maturation and fertilization. On day 5 post-fertilization, embryos were treated with either 0 (CONT; 1% BSA) or 100ng/mL recombinant bovine IL6. On day 7.5 post-fertilization, individual embryos (blastocyst stage) were loaded into transfer straws. Estrous synchronized beef (n = ) and dairy (n = ) cow recipients were allocated into treatment groups in the following manner. A subset of cows from each group underwent fixed-time AI (n=37). Remaining cows underwent embryo transfer (ET) in the uterine horn ipsilateral to a corpus luteum; 51 of these cows received a CONT embryo and the remaining 35 cows received an IL6 embryo. Thus, there were three treatment groups: AI, CONT, and IL6. Embryo and fetal measurements were performed via transrectal ultrasonography weekly from day 28 to 56, these included crown-rump length, crown-nose length, abdominal diameter, and amniotic vesicle. Pregnancies that remained throughout the entirety of the experiment 40.0% for IL6 (14/35); 19.6% for CONT (10/51); and 32.4% for AI (12/37). In summary, IL6 treatment of embryos produced pregnancies with characteristics more similar to the current industry standard of AI, rather than conventionally cultured embryos (CONT), supporting the hypothesis that IL6 supplementation to bovine embryos on day 5 post-fertilization improves developmental competency of in vitro produced embryos.

published_or_final_version / Obstetrics and Gynaecology / Master / Master of Medical Sciences

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The clinical manifestations of hemolytic disease of the fetus and newborn mediated by anti-K, an antibody of the Kell blood group system, are distinguishable from the classical form of the disease. Affected fetuses have low numbers of circulating reticulocytes and antibody titers and bilirubin levels are not reliable predictors of anemia. These observations suggest that antibodies to Kell glycoprotein lead to anemia through suppression of erythropoiesis. This study established a liquid erythroid progenitor cell culture model in which to perform analyses on the mechanism of the suppressive growth effect of anti-Kell glycoprotein. Using this culture model, this study demonstrated the requirement for co-ligation of Kell glycoprotein by a bivalent antibody for growth suppression. The absence of markers of apoptosis in cell cultures treated with anti-Kell glycoprotein suggests that the mechanism of growth suppression is distinct from programmed cell death and necrosis. Furthermore, this growth suppression cannot be rescued by erythropoietin.

1 v. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 1993

<p>The intention of the study is to evaluate the risk of artemisinin in early pregnancy through the use of a qualitative research approach, with a focus on rural women in Babati District, Manyara Region, Tanzania.</p><p>Artemisinin-Based Combination Therapy (ACT) is the most effective and recommended antimalarial treatment at the present. Artemisinin compounds are extracted from <em>Artemisia annua</em><em>, </em>a plant which has been used as an herbal medical treatment in China for 2000 years.</p><p>Except few side-effects, there have not been any reports on medical problems due to artemisinin intake during pregnancy. On the other hand, artemisinin tested on animals have revealed that complications such as death of embryos are possible during pregnancy, why more research is needed concerning artemisinin safety in first trimester of pregnancy.</p><p>However, evaluating the risk of artemisinin in pregnancy is referred as complex, when numerous factors could contribute to e.g. fetal loss, abnormalities, or wrong medication. Cultural and economical aspects have to be considered when designing a monitoring system, to enable effective registration of drug quality and drug intake, and follow-up study of mother and child. Accessibility, affordability, possibility and knowledge, are other significant related aspects that have to be managed to eliminate the risk of artemisinin in early pregnancy.</p><p> </p><p><strong></strong></p><p> </p><p> </p>

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.