[Truncated abstract] The dramatic increase in the expression of allergic diseases such as asthma and allergy over the last 20-30 years has highlighted the urgent need to identify causative factors. It was hypothesised that direct immune interactions between mother and fetus contribute to the cytokine milieu of pregnancy, thus influencing immune maturation after birth. Further it was speculated that the cytokine responses produced as a result of maternalfetal interactions are Th-2 skewed in women allergic disease, which programmes their offspring towards developing an allergic phenotype after birth. To test this hypothesis a cohort of 169 pregnant women were recruited at 20 weeks gestation and defined as allergic or non-allergic based on both clinical history and skin prick test sensitisation. These women and their infants were followed up throughout pregnancy (20 weeks, 30 weeks, 36 weeks gestation and 6 weeks post-partum) and up to 2.5 years of age. Mixed lymphocyte reactions (MLR) were used to measure maternal cytokine (IL-6, IL-10, IL-13 and IFN-) and lymphoproliferative responses to fetal alloantigens at each pregnancy time-point. Human leukocyte antigen (HLA) typing of mothers and infants were performed to assess the effect of HLA mismatch on maternal MLR responses to their fetus. After delivery, mononuclear cells (MNC) were isolated from cord blood (CB) and stimulated with allergens, mitogen and toll-like receptor (TLR) ligands. .... As IL-6 also participates in adaptive immunity by promoting Th-2 differentiation it is proposed that the production of IL-6 as a results of maternal encounters with paternal antigens during pregnancy, contribute to the Th-2 skewed responses observed universally in most infants at birth. Associations between maternal-fetal interaction and clinical outcomes in infancy: Although clinical signs of allergy in infancy were not the main outcome measure of this thesis, there were interesting, yet complex relationships between the production of these maternal cytokines towards the fetus and allergic disease at infant follow-ups. Increased maternal IFN-¿ to fetal alloantigen was associated with asthma at 2.5 years and a trend towards recurrent wheeze at 12 months. In contrast decreased maternal IL-13 production was associated with IgE mediated food allergy at 12 months. Adjusting for maternal allergy and other potential confounders including infant gender, method of delivery, HLA mismatch, and paternal allergy did not account for these relationships. Further follow-ups of these infants are required to determine if these relationship last in to early childhood. In conclusion, the findings of this thesis provides further support for the hypothesis that immune responses at birth are programmed prenatally, and that this programming has implications later in life. Importantly, the placenta is the immunologically active interface between mother and fetus during pregnancy. Therefore it is emphasised that there is a crucial need for future research to focus on early immune programming at the placental level before the aetiological pathways of immune mediated diseases can be fully elucidated.

Thesis (M.S.)--University of Michigan, 1981.

Thesis (M.S.)--University of Michigan, 1981.

Bovine genital campylobacteriosis is a disease of difficult diagnostic because of the microaerophilic nature of its etiologic agent, Campylobacter fetus, thereby causing the prevalence related to this disease to be underestimated. The purpose of this study was to evaluate the utilization of PCR for the diagnosis of genital campylobacteriosis, using samples obtained from bull prepuce aspirate, cow cervical mucus, and abomasum contents obtained from aborted fetuses, collected in transport and enrichment medium. Five different DNA extraction protocols were tested: thermal extraction, lyses with proteinase K, lyses with guanidine isothiocyanate, lyses with DNAzol? , and lyses with CTAB. The specificity, sensitivity and technical application of PCR assay were also evaluated with clinical samples. The PCR performance was compared to the culture technique for bacterial isolation. The CTAB was the most efficient extraction protocol; the pair of primers used was shown to be specific; and the limit of detection was of 63 CFU of Campylobacter fetus. PCR demonstrated that 24% (68/277) of the clinical samples were positive for Campylobacter fetus, while only 2.8% (8/277) of samples were positive by culture techinque. These results indicate that the PCR technique is specific and sensitivy, and is superior to the culture for the diagnosis of bovine genital campylobacteriosis. / A campilobacteriose genital bovina, caracterizada principalmente por infertilidade, é uma doença de difícil diagnóstico, devido à natureza microaerófila do seu agente etiológico, o Campylobacter fetus, tendo assim sua prevalência subestimada. Este trabalho teve por objetivo avaliar a utilização da técnica de PCR para o diagnóstico da campilobacteriose genital bovina, utilizando amostras de aspirado prepucial, muco cervical e conteúdo abomasal de fetos abortados, coletadas em meio de transporte e enriquecimento; bem como comparar seu desempenho com a técnica do isolamento bacteriano. Foram testados cinco diferentes protocolos de extração de DNA de Campylobacter fetus: termo extração, lise com proteinase K, lise com isotiocianato de guanidina, lise com DNAzol? e lise com brometo de cetiltrimetilamônio (CTAB). Também foram avaliadas a especificidade, a sensibilidade e a aplicação da técnica da PCR em amostras clínicas. Os resultados indicaram que o CTAB foi o protocolo de extração mais eficiente; o par de primers utilizado mostrou-se específico; e o limite de detecção foi 63 unidades formadoras de colônias (UFC) de C. fetus. A PCR encontrou 24% (68/277) das amostras clínicas positivas para C. fetus, enquanto a cultura encontrou 2,8% (8/277). A técnica da PCR é específica e sensível, e mostra-se superior a cultura no diagnóstico da campilobacteriose genital bovina.

Diaplacentar deoxynivalenol intoxication in porcine fetuses. Are histomorphological and immunohistochemical investigations at the 70th day of gestation a helpful diagnostic tool?

Univ., Diss.--Bremen, 2003. / Literaturverz. S. 317 - 361.

Thesis (MMed)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: Background: Studies about management of prolonged pregnancy dealt with pregnancy with certain gestational age, confirmed with early ultrasound scans. Objective: The primary aim for the study is to review the current management of uncertain gestational age (GA) post term pregnancy in Tygerberg Academic Hospital (TBH). Women at 42 weeks with an uncertain GA and an amniotic fluid index (AFI) of ≥ 10 cm as well as reassuring cardiotocographs (CTG) would be assessed to determine whether follow up over one week or two weeks are required. Method: A retrospective descriptive study included all patients with an uncertain gestation of 42 weeks referred to TBH. Results: A total of 135 pregnant women were studied. Booking fundal height (BFH) was used to determine GA in 99% and last menstrual period (LMP) in 1% of patients. The time interval between first evaluation at 42 weeks and delivery varies between 0 to 46 days (median 10 days); 104 women delivered vaginally (71% spontaneously, 6% after induction of labour (IOL)); 31 women (23%) by caesarean section; 1 elective, 4 due to cephalopelvic proportion (CPD), 5 had failed IOL, 3 poor progress and 18 fetal distress. Out of the total 11 (8%) women with AFI ≥ 10 had caesarean sections for fetal distress within 2 weeks of the visit at 42 weeks. No neonatal morbidity or mortality was noted in this study. Conclusion: Weekly monitoring with AFI and CTG for women at 42 weeks with unsure gestation is safe. A follow-up following 2 weeks cannot be recommended as 8% of women required caesarean sections within less than 2 weeks due to fetal distress. / AFRIKAANSE OPSOMMING: Agtergrond: Studies oor verlengde swangerskap handel oor swangerskappe met seker swangerskapsduurte, bevestig met vroeë ultraklank skandering. Doelwit: Die primêre doelwit van die studie is om die huidige hantering van verlengde swangerskap met onseker swangerskapsduurte by Tygerberg Hospitaal (TBH) te beoordeel. Vroue wat volgens onseker swangerskapsduurte 42 weke swanger is met ‘n amnionvogindeks (AVI) van >10 en gerusstellende kardiotokogramme (KTG) sal nagegaan word om te bepaal of opvolg oor een of twee weke nodig is. Metode: ‘n Retrospektiewe studie wat alle pasiënte insluit wat na Tygerberg Akademiese Hospitaal verwys word wat ‘n onseker swangerskapsduurte van 42 weke het. Resultate: ‘n Totaal van 135 vroue is bestudeer. Die fundale hoogte is gebruik om swangerskapsduurte te bepaal in 99% van gevalle en die laaste menstruasie in 1%. Die tydsinterval tussen die eerste evaluasie op 42 weke en verlossing wissel tussen 0 en 46 dae (mediaan 10 dae); 104 vroue het ‘n vaginale verlossing gehad (71% met spontane aanvang van kraam, 6% na induksie van kraam); 31 (23%) is met keisersnitte verlos; 1 elektief, 4 as gevolg van skedelbekken disproporsie, 5 gefaalde induksies, 3 swak vordering en 18 met fetal nood. Uit die totaal was daar 11 (8%) vroue met ‘n AVI ≥ 10 wat keisersnitte vir fetale nood binne 2 weke van die besoek op 42 weke gehad het. Geen neonatale morbititeit of mortaliteit het in die studie voorgekom nie. Gevolgtrekking: Weeklikse monitering met AVI en KTG vir vroue wat 42 weke swanger is met onseker swangerskapsduurte, is veilig. Opvolg na 2 weke kan nie aanbeveel word nie want 8% het keisersnitte vir fetale nood gehad na minder as 2 weke.

Bovine Genital Campylobacteriosis is characterized by early pregnancy loss and temporary infertility in cattle. The purpose of this project was to compare diagnostic approaches to detect Campylobacter fetus subsp. venerealis and evaluate the efficacy of vaccination for Bovine Genital Campylobacteriosis. This thesis describes the results of two studies that compared different sample preparation methods for bovine vaginal mucus for real-time PCR and assessed a commercial vaccine in preventing infection and reproductive loss. The first study compared real-time PCR utilizing different bovine vaginal mucus sample preparation techniques to direct culture. The magnetic bead based protocol demonstrated higher sensitivity (48.4%, P=0.02) and lower specificity (78.9%, P=0.01) than the heat lysis protocol which involved an additional dilution step (Sens=29.4%, Spec=88.2%), but did not differ from the heat lysis protocol without sample dilution (Sens=35.0%, P=0.16; Spec=81.1%, P=0.62). The sample preparation method, designed for bovine preputial samples (Chaban et al. 2012. Can J of Vet Res; 76: 166), did not work well for vaginal mucus. All modifications of that method and magnetic bead based extraction technique had low sensitivity compared to culture probably due to the biophysical properties of vaginal mucus, which could cause loss of targeted DNA during processing, or repeated sample freezing and thawing. Release of DNA directly from vaginal mucus by a modified heat lysis protocol with consequent real-time PCR could be a promising rapid screening approach after validating on fresh samples. The second study compared the risk of infection and reproductive failure in heifers, vaccinated with a commercial multivalent vaccine containing C. fetus antigen, to heifers vaccinated with a comparable product without C. fetus, that were exposed to infected bulls. There was no significant difference between groups either in risk of Campylobacter fetus subsp. venerealis isolation (P>0.17) or in the proportion of heifers that cultured positive at least once (P=0.42), as well as in the median number times of cultured positive samples (P=0.24) and the time to first cultured positive (P=0.67). There was no difference by treatment in the weekly proportions of heifers diagnosed pregnant by either ultrasound (P>0.31) or serum concentration of pragnancy specific protein B (P>0.31) during the study, as well as in the time to first pregnancy for heifers ever diagnosed as pregnant (P=0.30) and those that remained pregnant at the end of the study (P=0.70). Similarly, the difference was not detected by treatment in the proportion of animals, ever detected pregnant during the study (P=0.57) and in pregnancy loss rates (P=0.28). However, heifers that aborted were 4 times more likely to be cultured positive than those that did not abort (P=0.01). Heifers that were not pregnant at the end of the study cultured positive 1.5 times more often than pregnant animals in treatment group (P=0.04), while in control group such difference was 4 times (P=0.01). Heifers that were not pregnant at the end of the study did not differ by treatment in the number of times cultured positive (P=0.14). In this study, the mean concentrations of ELISA antibodies to C. fetus after vaccination were more than 2 times higher in treatment group than in control group (P<0.02), but vaccination did not significantly reduce infection or improve pregnancy in heifers when exposed to Cfv-infected bulls. Sample preparation technique is important for successful real-time PCR; release of DNA directly from a CVM sample by a modified heat lysis protocol was easy to perform and could be promising as a rapid screening approach for Bovine Genital Campylobacteriosis after validating on fresh samples. Vaccinating of heifers with a polyvalent commercial vaccine, containing Campylobacter fetus antigen, according to the label, did not significantly reduce infection rate or improve reproductive performance when they were naturally challenged.

published_or_final_version / abstract / Obstetrics and Gynaecology / Doctoral / Doctor of Philosophy

published_or_final_version / Obstetrics and Gynaecology / Master / Master of Philosophy