A RESEARCH REPORT SUBMITTED TO THE UNIVERSITY OF THE WITWATERSRAND IN FULFILLMENT OF THE MASTER OF MEDICINE DEGREE / Introduction South Africa has a high prevalence of unintended pregnancies and HIV. Sixty eight thousand women die due to unsafe abortion annually worldwide, making it a leading cause of maternal mortality. In SA the maternal mortality has decreased from TOP. Maternal mortality from HIV is the leading cause of maternal mortality in South Africa. Unintended pregnancies are mainly a consequence of inconsistent and incorrect contraceptive use. The condom is the only contraceptive method which has the dual ability of preventing HIV and unintended pregnancies. We postulate that the failure of barrier contraception is a risk for both HIV and unwanted pregnancy. This study describes the contraceptive methods used by women at a TOP clinic and evaluates the use of barrier contraceptives amongst women requesting TOP, and the prevalence of HIV. Methods CHBAH is tertiary hospital in Southern Gauteng. Women with medical or surgical comorbidities that request a TOP are referred to the hospital. A prospective study using a cross sectional study design was performed at the Chris Hani Baragwanath Academic Hospital TOP clinic between February and October 2011. Data was collected using interviews and medical files. Results One hundred and nineteen women were interviewed. Most women 56 (47.06%) did not use any contraception at the time of conception. The most common reason for TOP was financial constraints, followed by relationship conflict. Pregnancy despite condom use was 34.45% (n=41). The percentage of women with condom failure, who were HIV positive was 34.14% (n=14). True condom failure was experienced by 12 women (pregnancy due to breakage/slippage of the condom. Conclusion Unintended pregnancy is mainly associated with not using contraceptives. The male condom was the most widely used contraceptive. The HIV prevalence in the group with condom failure was higher than the general antenatal population. There is a need for education regarding correct and consistent use of contraception.

The last stage of a deflagration-to-detonation transition (DDT) process involves the propagation and acceleration of a fast flame. This process is currently poorly understood. The difficulties lie in its complex structure, which is turbulent and involves multi-dimensional gasdynamic phenomena. Previous experimental studies have established these fast flames from the interaction of a detonation wave with a row of obstacles or porous plate. Two main questions remain unsolved: 1) What is the propagation speed of the fast flame obtained in these configurations and 2), Which factors dominate the occurrence of the DDT phenomenon? To answer these questions, two models have been constructed in the present work. Firstly, a quasi-1D gasdynamic model is proposed for estimating the transmitted reaction front speed and the strength of the transmitted shock. By alternately assuming a Chapman-Jouguet (CJ) deflagration or an inert shock, the model estimated the transmitted shock speeds. The comparison with extensive experimental data for a range of hydrocarbon fast flames revealed that the burning velocity required for transition to detonation was the CJ value. Secondly, a numerical shock-induced ignition model, which can impose mechanical fluctuations from a driven piston, was established in order to investigate the ignition and acceleration process, thereby clarifying the other question of interest. The results from the simulations indicated that the mechanical fluctuations can play an important role in triggering DDT by means of promoting the local ignition and amplification of the reaction front stemming from such ignition. It was also found that the maximum amplification effects occur with a fluctuation period between the non-fluctuated ignition delay and the time scale of chemical energy deposition. The inert simulation results show that two types of gasdynamic effects from the fluctuations were vital to the hot-spot formation. These hot spots make significant contribution to the detonation initiation.

O conhecimento da incidência e das características do aborto provocado, sobretudo o ilegal, é de grande interesse tanto para a Saúde Pública, como para a Demografia. Não obstante, poucos são os estudos na América Latina e no Brasil, que se propõem a investigar sua ocorrência. Ocorre que a conotação de \"crime\", que lhe é atribuída, dificulta sobremaneira sua abordagem. A presente pesquisa foi realizada entre 2.000 mulheres em idade fértil - 15 a 49 anos -, residentes no sub-distrito de Vila Madalena, São Paulo, Brasil, com o objetivo central de aprofundar o conhecimento do aborto provocado, relacionando-o a variáveis sociais, econômicas e demográficas, reconhecidamente ligados à sua ocorrência, e, especialmente à fecundidade. Em caráter experimental, utilizou-se a Técnica de Resposta ao Azar (TRA) que, segundo a literatura internacional, propicia a obtenção de informação mais fidedigna. A avaliação da viabilidade deta técnica é outro objetivo da pesquisa. Pela TRA pôde-se estimar que 41 em cada 1.000 mulheres, provocaram um aborto em 1987, enquanto apenas 8 em 1000 mulheres admitiram, por abordagem direta, terem provocado um aborto nesse período. Os resultados confirmam, por um lado, omissões voluntárias de informação e, por outro, a conveniência de se trabalhar com a TRA. A análise de diferenciais dos abortos ocorridos no transcorrer da vida reprodutiva, identificou as não casadas, as sem nascidos vivos, as com menor nascimentos que o desejado, as que possuem entre 15 e 19 anos de idade, as que verbalizaram aceitar a prática do aborto provocado em qualquer circunstância, como sendo as categorias de mulheres que ao engravidarem, recorrem com maior intensidade ao abortamento provocado. Mediante o estabelecimento de paralelismos entre TRA e abordagem direta, pôde-se evidenciar que as mulheres que mais omitem informação são, em geral, as que mais abortam. A elaboração dos modelos multivariados, por sua vez, permitiu evidenciar que, não possuir restrições à prática do aborto e não ser casada, são potenciais fatores de risco. Ao que tudo indica, enquanto as mulheres não casadas, particularmente as solteiras, recorrem ao aborto para se livrarem de uma gravidez indesejada, as casadas o buscam para manter o número de filhos dentro dos limites desejados ou para espaçar um nascimento de outro. Há razões para se suspeitar que a prática do aborto se intensificará em nosso meio, num futuro próximo. Ao que parece, nem a renda familiar nem a escolaridade, intervêem na opção da mulher pelo aborto. Enfim, apesar das dificuldades existentes em se trabalhar o tema aborto, os resultados conseguidos nesta pesquisa, deste ponto de vista, superaram a expectativa, fundamentalmente, em função do sucesso da TRA. / The incidence and associated factors related with illegal induced abort are areas of interest for Public Health and Demography. Nevertheless, there are few studies in Brazil and others countries of Latin America about it. It\' s possible that this omission can be justified by the fact that abort is considered crime in these countries. This study looks toward filling this lack of infonnation. An specific questionnaire was used to get more trustworthy information, the Randomized Response Technic (RRT). The results of this questionnaire were compared with the usual direct way of getting information. Social, economic and demographic variables related with fertility were studied. The studied population was two thousand women between 15 and 49 years old, the fertile period. They live on Vila Madalena, a neighborhood of São Paulo city, Brazil. The estimate incidence of induced abort in 1987 by RRT was 41/1000 women and by the usual direct way was 8/1000 women. This difference justify the use of the RRT in this kind of research. It was observed that women who more omit information, have more history of abort. The univariate analyses identified the following associated factors with induced abort: not married, without lifeborn children, age between 15 and 19 years old, those who accept the practice of induced abmt in any circumstance, and women with less children then desired. At the multivariate analyses, it remained in the model the following factors: not married and accept the practice of induced abort in any circumstance. Family income and schoollevel were not associated with induced abort in this studied population. The results are coherent with what it\'s expected and they demonstrate the value of the RRT questionnaire.

Thesis (M Med (Anaesthesiology)) -- University of Limpopo, 2013. / Purpose: The purpose of this study was to determine whether etomidate should be the induction agent of choice for Rapid Sequence Intubation in the Emergency department due to its haemodynamic stability. Objective: To measure the haemodynamic effects of etomidate post- induction in patients undergoing Rapid sequence intubation. Methods: This was a prospective, randomized, observational and unblinded study. The study was conducted at DR GEORGE MUKHARI HOSPITAL theatre unit on 45 patients between the ages of 11 and 65 years of age who fall under the American Society of Anaesthesiology classification (ASA) IE – IIIE. Each patient had an established intravenous line, was pre-oxygenated and then received etomidate (0.2 mg – 0.3 mg/kg). Cricoid pressure was applied immediately following loss of consciousness. Suxamethonium 1.5 mg/kg or Rocuronium 1.2 mg/kg was administered and this was followed by endotracheal intubation 60 seconds later. Data collected included amongst others vital signs:- Heart Rate, Systolic Blood Pressure, Diastolic Blood Pressure and Mean Arterial Pressure which were measured pre-induction, immediately post-intubation, 2.5 minutes, 5 minutes and 7.5 minutes later by a non invasive automated blood pressure monitor. Statistical Analysis: Descriptive statistical analysis was applied using the SPSS (Statistical Programme for Social Sciences) to demonstrate the demographics and ASA classifications of the patients in the study. Mean standard deviations were calculated for both males and 10 females in the study. Changes in vital signs immediately post-intubation were graphically demonstrated. The changes in vital signs (HR, SBP, DBP and MAP) were calculated and differences in such changes over-time were expressed as p-value. Significant differences in changes of the vital signs were noted if p ≤ 0.05. Results: The blood pressure increased immediately following intubation due to laryngoscopy and intubation. As anaesthesia progressed (i.e. 2.5 minutes, 5 minutes and 7.5 minutes later) the blood pressure gradually declined to levels lower than pre-induction values but at acceptable levels. Conclusion: Etomidate is an effective anaesthetic induction agent as it is haemody-namically stable and thus should be used in an Emergency department

Models of steroid-induced hypertension in man and rat have been well characterized but the mechanisms by which ACTH and glucocorticoids raise blood pressure are not fully understood. Recently described paracrine (eg endothelial nitric oxide) and humoral (eg PHF) factors may be important in human essential hypertension. These factors were examined in cortisol-induced hypertension in man and ACTH-induced hypertension in the rat respectively. In man, the haemodynamic effects of ACTH can be attributed to the adrenal production of cortisol, but whether the major rodent glucocorticoid corticosterone is responsible for ACTH-induced hypertension in the rat has not been resolved. This question was examined in these studies. In male volunteers, exogenous cortisol raised blood pressure and suppressed endothelium-dependent vasodilatation, by a mechanism which may be nitric oxide synthase dependent. Although dexamethasone and fludrocortisone also raised blood pressure, attenuation of cholinergic vasodilatation was not observed. From these studies, the data suggest that the effect of cortisol on endothelium-dependent vasodilatation is unique to the endogenous hormone and not reproduced by synthetic agonists of GR or MR. Impaired endothelial vasodilator function may contribute to cortisol-induced hypertension in man. In the rat, exogenous corticosterone, administered in doses to achieve circulating concentrations similar to those observed in the experimental model of ACTH excess, reproduced the haemodynamic and some of the metabolic changes which characterize ACTH-induced hypertension. Further, like ACTH-induced hypertension, corticosterone-induced hypertension was prevented by L- but not D-arginine, and this effect was completely prevented by NOLA. It is likely that adrenal corticosterone mediates the hypertensive effects of ACTH excess. Parathyroidectomy had no significant effect on the rise in blood pressure secondary to ACTH excess. It is unlikely that PHF contributes to the model of ACTH-induced hypertension in the rat. The bioassay for the measurement of PHF could not be reproduced in our laboratory, leaving a question mark about the relevance of this putative factor in hypertension research.

Thymidine kinase is a key enzyme in the nucleotide salvage pathway, catalyzing the production of dTMP from thymidine and ATP. In order to identify the structural features of the TK protein and/or primary amino acid sequences which contribute to the catalytic and regulatory activities of this enzyme, an in vitro transcription and translation system has been used in concert with protein engineering techniques for the production and phenotypic characterization of mutant and wild-type TK enzymes. Because of discrepancies in the literature regarding the quaternary structure of the VVTK, the native molecular weight and quaternary structure was determined to be an 80kDa homotetrameric enzyme by glycerol gradient fractionation, gel filtration and glutaraldehyde cross-linking analyses. Computer-assisted alignment of the predicted amino acid sequences derived from cellular and poxvirus TK genes identified seven highly-conserved domains distributed throughout the VVTK polypeptide (domains I-VII). Domain I (amino acid residues 11-18 ) exhibits a high degree of similarity to both ATP and GTP binding site consensus sequences, although the VVTK utilizes only ATP as a phosphate donor. Site directed mutagenesis and ATP-agarose affinity chromatography techniques were employed to confirm that this region was responsible for ATP binding and to determine which amino acids were essential for efficient binding. The TK gene (tdk) from E. coli was isolated and sequenced to serve as a prokaryotic enzyme with which to compare VVTK. The alignment revealed only 23% shared identity with VVTK and, interestingly, the identical and similar residues were clustered into three of the seven domains identified previously (domains I, III and VII). Preliminary evidence supports domain III (residues 78-90) as a putative magnesium binding site and that a highly conserved cysteine residue (cysteine 170) within domain VII (residues 168-171) may be a component of the catalytic site. Secondary structure alignment between Herpes Simplex Virus (HSV) TK and monkeypox TK (a close relative of VVTK) revealed that the putative nucleoside binding site of HSVTK aligns with residues within domain IV. Replacement of a VVTK residue (Q114) with the corresponding residue of HSVTK (an aspartic acid) greatly alters the substrate specificity and dTTP sensitivity of VVTK. / Graduation date: 1991

The effects of response-independent mirror presentation schedules on the swimming behaviour of Betta splendens were studied in two experiments. In experiment 1, four fish received alternating baseline (no mirror) and fixed-time (FT) 2-min or variable-time (VT) 2-min mirror presentation conditions. Two fish consistently showed increased rates of mirror-side lap-swimming (MSLS; a back-and-forth swimming pattern) and decreased distance from the mirror during the inter-stimulus intervals (ISIs) of FT and VT sessions, and during baseline sessions that followed FT and VT phases. Data from one fish indicated that a VT schedule might increase both proximity to the mirror and MSLS rates that have decreased on FT. Therefore, in experiment 2 three fish from experiment 1 received alternating FT and VT conditions. Proximity to the mirror and MSLS rates increased during VT phases relative to FT phases in two fish, though effects were small and did not occur across all alternations. Additional findings were that MSLS during ISIs tended to increase within FT phases, that MSLS generally occurred either at a steady rate within ISIs or showed a scalloped effect, that mirror presentations produced approach to the mirror side that persisted during ISIs and subsequent baseline phases, and that mirror-side distance during the mirror presentations was less than during the ISIs. Although the findings were not consistent across all fish, they were replicated a number of times within at least two of the fish. The findings are discussed in terms of adventitious operant conditioning, respondent conditioning, and the behaviour systems approach. The results of this study increase the generality of response-independent schedule effects on locomotive behaviour. / May 2009

Many chromophoric organics and polymers are highly emissive in their dilute solutions but become weakly luminescent in the high concentration and solid film states due to the induced £k−£k interactions of the intimately-contact chromophores. Therefore, it is practically important to develop fluorescent organic and polymeric materials with enhanced emission in their aggregated states (so called aggregated-induced emission, AIE). In this study, organic compound 2,4-diphenylquinoline (DPQ) with inherent quinoline ring and polymeric poly(vinyl diphenylquinoline) (PVQ) with pendant quinoline group were prepared and their AIE-phenomena were characterized. To prove the reported point that restriction of intramolecular rotation (RIR) is the main cause for AIE effect, DPQ and PVQ were further incorporated with organic strong acid of camphorsulfonic acid (CSA). Through the favorable acid-base interaction between the sulfonic acid in CSA and the nitrogen atom of the quinoline ring in DPA (or CSA), ionic complex of DPQ-CSA (and PVQ-CSA) was easily prepared and their response toward AIE properties were studied. Through the enhanced RIR by the complexation of bulky CSA with the central quinoline ring, the resulting DPQ-CSA (and PVQ-CSA) complex was proved to have better AIE-effect compared to the pristine DPQ (and PVQ). RIR mechanism can be indirectly proved in this case. We study the AIE on micelle topics of the block copolymer. We choose the poly(styrene-block-tertbutylstyrene) (PS-b-PBS) as our block copolymer. To synthesize the PS-b-PBS, we can successfully get the new block copolymer PVQ-b-PBS. PVQ-b-PBS was similarly blended with the CSA. In the block copolymer micelles, choose the selective solvent to get the different micelles and observe the diverse on the luminescence. Finally, we analyzed compositions and conformations by atomic force microscopy (AFM) and transmission electron microscopy (TEM).

Temperature affects the sexual differentiation and the development of brain of tilapia, Oreochromis mossambicus. Expressed sequence tags ( EST ) derived from the developing tilapia brain had been cloned in our laboratory. In the present study, we focus on the promoter of cold-induced protein. The promoter sequence of cold-induced protein from the transcription start site ( TSS ) were cloned by 5¡¦ rapid amplification of cDNA end ( 5¡¦-RACE ) and Genome Walker DNA Walking. The bioinformatic analysis was performed on the fragment for predicting the transcription factor binding site. We used the digestion method of restriction enzymes and an electrophoresis mobility shift assay to find transcription factor binding site. The results indicated that there is a putative POU3F2 binding site in the fragment form -157 bp to -149 bp. The luciferase activity assay was performed on this site and results indicated that wild type showed the enhanced promoter activity. However, site-direct mutagenesis of this site did not result in the reduction of the promoter activity.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 92-100).