No description available.

No description available.

The influence of experience during brain development was investigated on juvenile behavior, adult amphetamine sensitization, and neuronal structural plasticity in rats. Two experiential factors (i.e., tactile stimulation and stress) were studied either before or soon after birth. Early experience feminized social behavior in males; however, only stress enhanced anxiety-like behavior in males. Repeated amphetamine administration resulted in the development and persistence of behavioral sensitization. However, tactile stimulation attenuated the drug-induced behavioral sensitization whereas stress failed to influence the degree of sensitization. Neuroanatomical findings revealed that early experience altered the cortical and subcortical structures. Furthermore, drug exposure reorganized the brain structures involved in addiction but early experience prevented the drug-associated changes. Early adverse experience influences the subsequent exposure to a drug of abuse at anatomical level whereas a favorable experience has an effect both at behavioral and anatomical levels and thus may play a protective role against drug-induced sensitization and addiction. / xii, 263 leaves : ill. ; 29 cm

Thesis (MScMedSc (Pathology. Medical Virology))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: In 2007, AIDS caused an estimated 2.1 millions deaths worldwide; about 70% in sub-Saharan Africa. HIV preferentially targets activated CD4 T cells, expressing the major HIV receptor CD4, as well as the major chemokine coreceptors CCR5 and CXCR4. These coreceptors play a prominent role during HIV cell entrance phase, HIV transmission and also disease progression. They have been found to be differentially expressed by CD4 T cell subsets. Tuberculosis coinfection may enhance immune activation in vivo thus accelerating HIV disease progression and has become a major challenge in the control of TB in Africa. Introduction of HAART has reduced disease progression to AIDS, as well as risk of further morbidity and mortality. HAART results in a rapid decline of viral load and an initial increase of peripheral CD4 count, however little is known on the effect of HAART in regulation of coreceptor expression, immune activation status and CD4 T cell subset distribution in HIV infection and HIV/TB coinfection. This study is a cross-sectional analysis of coreceptor expression, immune activation status and CD4 T cell subpopulation distribution in South African HIV and HIV/TB coinfected patients before and after ARV. A total of 137 South African individuals were investigated, comprising 15 healthy normal donors (healthy subgroup), 10 patients with active pulmonary tuberculosis (PTB subgroup), 33 HIV-1 positive patients without active PTB (HIV subgroup), 23 positive patients with active PTB (HIV/PTB subgroup), 36 HIV-1 positive patients on ARV (HIV on ARV subgroup) and 20 HIV-1 positive patients with active PTB on ARV (HIV/PTB on ARV subgroup). CD4 absolute count and plasma viral load were determined for all donors. Freshly isolated PBMC were classified by flow cytometry into the following CD4+ T lymphocyte subsets: naïve (CD45+, CD27+), effector memory (CD45-, CD27-), central memory (CD45-, CD27+), and effector (CD45+, CD27-). Coreceptor expression and activation status was assessed by CCR5, CXCR4 and CD38 expression on CD4 T cell subsets. HIV, TB and HIV/TB coinfection was associated with a decrease in percentage CCR5+ T cells as compared to healthy controls, with the HIV/TB group showing the most extensive decrease. In treatment naive patients, CD4 T cells showed elevated surface expression of CCR5 and CD38 as determined by mean fluorescence intensity in HIV/TB co-infection compared to HIV infection alone. The percentage of antigen-experienced cells was higher in the HIV/TB co-infected group compared to the HIV group. The percentage of naïve T cells was decreased in both the HIV infected and the HIV/TB co-infected groups compared to healthy controls. HIV patients with more than 6 months of ARV showed decreased CCR5 and CD38 surface level expression in the HIV and the HIV/ TB co-infected subgroups. An increased percentage of naïve T cells was observed in the HIV infected subgroup, but not in the HIV/TB subgroup, similarly, a decreased percentage of antigen-experienced cells was observed in the HIV subgroup, but not in the HIV/TB co-infected subgroup. A positive correlation was found between CCR5 and CD38 expression, and CXCR4 and CD38 expression (Spearman coefficient of correlation respectively: r=0.59, p<0.001 and r=0.55, p<0.001). Furthermore we found plasma viral load positively associated with CD38 expression (r=0.31, p<0.001) and percentage activated CCR5+ expressing CD4 T cells positively related to viral load (r=0.31, p<0.001). Percentage naïve CD4 T cells was positively associated with CD4 count (r=0.60, p<0.001) and negatively correlated to viral load (r=-0.42, p<0.001). These results indicate that TB coinfection exacerbates certain aspects of dysregulation of CD4 T cell homeostasis and activation caused by HIV infection. In addition, ARV-associated decrease in coreceptor expression, immune activation status and a normalisation of CD4 T cell subset distribution was observed in HIV infected individuals, but not in HIV/TB coinfection. Despite viral suppression after ARV treatment, the decline in the immune activation marker CD38 and coreceptor CCR5 expression, increase in percentage naïve CD4 T cells and decrease of antigen-experienced cells did not reach the levels displayed in the healthy control group. This may indicate that ongoing (albeit reduced) T cell immune activation may occur in the presence of ARV. Further longitudinal studies are needed to closely monitor immune activation during ARV treatment. This study highlighted an association of TB disease with immune activation in HIV infection, the importance of T-cell activation in HIV pathogenesis and its impact on ARV treatment. Further studies are needed to identify causative factors that may lead to a persistent immune activation status during ARV treatment, and how TB coinfection confounds normal responses to ARV. / AFRIKAANSE OPSOMMING: In 2007 was ongeveer 2.1 miljoen sterftes wêreldwyd veroorsaak deur VIGS; ongeveer 70% in Sub-Sahara Afrika. CD4 T selle is die hoof teiken van MIV, aangesien dit die primêre CD4 reseptor, sowel as een of beide van die vernaamste chemokien koreseptore CCR5 en CXCR4 vrystel. Hierdie koreseptore speel ‘n prominente rol wanneer die MIV die sel binnedring, asook tydens MIV oordrag en verloop van die siekte. Dit word ook deur verskillende fraksies van CD4 T selle vrygestel. Gelyktydige TB infeksie mag immuunaktivering in vivo verhoog en dus die siekeproses versnel. MIV het ‘n groot uitdaging geword in die beheer van TB in Afrika. Bekendstelling van HAART het die ontwikkeling van VIGS vertraag, asook die risiko van verdere morbiditeit en mortaliteit. HAART veroorsaak ‘n vinnige afname in virale lading ‘n toename in CD4 telling, hoewel die spesifieke invloed van HAART op die regulering van koreseptor vrystelling, immuunaktivering en verspreiding van CD4 fraksies in MIV en MIV/TB infeksies nog onduidelik is. Hierdie studie het gepoog om koreseptor vrystelling, immuunaktiveringstatus en die verspreiding van CD4 subpopulasies in pasiënte met MIV en MIV/TB voor en na ARV behandeling te ondersoek. ‘n Totaal van 137 Suid-Afrikaanse individue is ondersoek en die studiegroep het bestaan uit 15 normale persone (gesonde subgroep), 10 pasiënte met aktiewe pulmonale TB (PTB subgroup), 33 MIV positiewe pasiënte sonder PTB (MIV subgroep), 23 MIV positiewe pasiënte met aktiewe PTB (MIV/PTB subgroep), 36 MIV positiewe pasiënte op ARV (MIV op ARV subgroep) en 20 MIV positiewe pasiënte met aktiewe PTB op ARV (MIV/PTB op ARV subgroep). Absolute CD4 telling en virale ladings was bepaal vir alle deelnemers. Vars geïsoleerde perifere bloed mononukleêre selle is geklassifiseer deur middel van vloeisitometrie as die volgende CD4 T limfosiet subgroepe: naïewe selle (CD45+, CD27+), effektor geheueselle (CD45-, CD27-), sentrale geheueselle (CD45-, CD27+), en effektor selle (CD45+, CD27-). Koreseptor vrystelling en aktivering was beoordeel volgens CCR5, CXCR4 en CD38 vrystelling op CD4 T sel subgroepe. HIV, TB en MIV/TB ko-infeksie is geassosieer met ‘n afname in die persentasie CCR5+ T selle, vergeleke met gesonde kontroles, waar die MIV/TB subgroep die grootste afname getoon het. In onbehandelde pasiënte het die CD4 T selle verhoogde vrystelling van CCR5 en CD38 op die oppervlakte getoon en dit is bevestig deur die gemiddelde fluoresserende vii intensiteit in die MIV/TB subgroep vergeleke met die subgroep met slegs MIV. Die MIV/TB subgroep het verder ook ‘n verhoogde persentasie totale geheue T selle getoon vergeleke met die MIV subgroep. Die persentasie naïewe T selle was egter verlaag in beide die MIV en MIV/TB subgroepe vergeleke met normale kontroles. MIV pasiënte wat langer as 6 maande op ARV behandeling was in beide die MIV en MIV/TB subgroepe, het ‘n verlaagde vrystelling van CCR5 en CD38 op die oppervlakte van die CD4 selle getoon. ‘n Verhoogde persentasie naïewe T selle het in die MIV subgroep voorgekom, maar nie in die MIV/TB subgroup nie. ‘n Soortgelyke tendens is gevind waar die persentasie totale geheueselle verlaag was in die MIV subgroep, maar nie in die MIV/TB subgroep nie. ‘n Positiewe korrelasie is gevind tussen CCR5 en CD38 vrystelling, asook CXCR4 en CD38 vrystelling (Spearman korrelasie koëffisiënt: r=0.59, p<0.001 en r=0.55, p<0.001 onderskeidelik). Verder het die plasma virale lading ‘n positiewe assosiasie getoon met CD38 vrystelling (r=0.31, p<0.001) en die persentasie geaktiveerde CCR5+ vrystellende CD4 T selle met virale lading (r=0.31, p<0.001). Die persentasie naïewe CD4 T selle het ‘n positiewe assosiasie getoon met CD4 telling (r=0.60, p<0.001) en ‘n negatiewe korrelasie met virale lading (r=-0.42, p<0.001). Volgens hierdie resultate vererger TB ko-infeksie sekere aspekte van die disregulasie van CD4 T selhomeostase en aktivering as gevolg van MIV infeksie. Verder kon ‘n ARVgeassosieerde afname in koreseptor vrystelling, immuunaktivering en normalisering van CD4 T sel fraksies bespeur word in die MIV subgroep, maar nie in die MIV/TB subgroep nie. Ten spyte van virale onderdrukking veroorsaak deur ARV behandeling, het die afname in die immuunmerker CD38 en koreseptor CCR5, toename in die persentasie naïewe CD4 selle en afname in totale geheue CD4 T selle nie die vlakke van die normale kontrolegroep bereik nie. Dit is moontlik dat volgehoue verlaagde T sel immuunaktivering nog steeds mag plaasvind in die teenwoordigheid van ARV. Verdere longitudinale studies is nodig om immuunaktivering tydens ARV behandeling te monitor. Hierdie studie het die belangrikheid van T sel aktivering in MIV patogenese en dit impak daarvan op ARV behandeling beklemtoon. Verdere studies is nodig om moontlike oorsake of bydraende faktore te identifiseer wat tot volgehoue immuunaktivering tydens ARV behandeling kan lei, asook tot mate waartoe TB ko-infeksie kan inmeng met die normale werking van ARV behandeling.

Thesis (MScMedSc)--University of Stellenbosch, 2011. / It is estimated that 32.8 million people are living with Human Immunodeficiency Virus (HIV) globally with the number of people receiving antiretroviral therapy in low- and middle- income counties increasing to more than 5 million people in 2009. These successes are threatened by treatment failure and the development of resistance to treatment. With an estimated 3.7% patients failing first line treatment after 2 years and 17.9% after 4 years on treatment there is a need for a practical and cheap in-house drug resistance assay that can be used to provide drug resistance data to clinicians and to use as a research tool to investigate drug resistance. In this study we attempted to optimize and validate an in-house drug resistance assay, adapted from Jacobs et al, 2008, to be used as a diagnostic tool and to study the presence of antiretroviral resistance in patients on the Western Cape Mother-To-Child-Transmission (MTCT) regimen. Quality control samples were received from The National Institute of Communicable Diseases AIDS Virus Research Unit, The Round Robin HIV-1 genotyping assessment system from the University of Würzburg and the QCMD assessment system were used for the optimization and validation of an in-house drug resistance assay. The ViroSeq™ HIV-1 Genotyping System was used for comparison of sample and mutation detection. It was possible to optimise and validate a genotyping assay for diagnostic testing and research use by comparison with the ViroSeq™ HIV-1 Genotyping System and evaluation with external quality assessment systems. This assay could subsequently be used to determine the development of genotypic-antiretroviral resistance in patients treated according to the provincial prevention of mother-to-child-transmission (PMTCT) protocol in the Western Cape (single dose nevirapine (sd-NVP), combined with a short course Zidovudine (AZT)). Patient samples were collected from pregnant women who took part in the Western Cape PMTCT program and visited the Tygerberg Obstetrics Clinic and Delft Community Hospital. EDTA blood was obtained to measure CD4-cell count, viral load, and to do genotyping for viral subtype and the presence of resistance mutations. Information on prior exposure to antiretroviral therapy was also collected. A detected resistance rate of 17.1% in this predominantly HIV-1 subtype C population is lower than previously recorded when sd-NVP was administered to HIV-1 subtype C positive patients in PMTCT programs. This could indicate that a dual PMTCT regimen including AZT and NVP reduces the risk of resistance to NVP relative to a regimen that uses sd-NVP. The genotyping assay uses four primers to amplify the PR and the RT gene separately to obtain PCR products, of 487 and 804 base pairs respectively for sequencing. The two PCR products were sequenced with three and five primers respectively to sequence the complete PR and approximately 250 amino acids of the RT gene. The sequences generated, thus, are analysed and aligned with the Sequencer V4.7 software to obtain a consensus sequence of approximately 1200 base pairs for analysis of resistance mutations in the protease and reverse transcriptase genes. The developed assay was hence further simplified and improved, by combining the PR and RT assay into one, which was optimised and validated for use in the routine diagnostic setting. The final genotyping assay uses 8 primers for sequencing to obtain a 1200 bp sequence for genotyping that contains the protease and the 5’ of the reverse transcriptase genes in which antiretroviral resistance associated mutations are found. The assay was accredited by SANAS in 2008.

Thesis (MEdPsych (Educational Psychology)--University of Stellenbosch, 2007. / Fetal Alcohol Syndrome (FAS) is an ongoing problem in the Western Cape. Marginalised and poverty-stricken communities use alcohol as a method of entertainment because it is freely available and relatively inexpensive. Due to a cycle of ongoing poverty and lack of education, many women drink large quantities of alcohol when they are pregnant or before they know they are pregnant. This causes the unborn baby to be severely at risk for FAS. There has been much research done in academic and social environments on the presentation and symptoms of FAS and of behaviour. Less research has been done surrounding the mother's experience of her FAS child, it is therefore my aim to research this gap in the research. This research study investigated the experience of mothers who raised children with FAS. Many mothers of children with prenatal exposure to alcohol feel conflict and guilt regarding their children and I attempted to find out what their general experience surrounding this was. Within this research topic I aimed to investigate the mothers' attitudes, their behaviour towards and their general perceptions of their developing child with FAS. This was viewed from an eco-systemic framework in which the mother is an integral part of different systems impacting and working together, that influence her maternal functioning. Finally, the aim of this research study was to ascertain how best mothers of FAS children could be supported. In this same process, I hoped, the mothers could learn to feel empowered to help and support their child, and in the process attempt to shift ongoing cycles of negative behaviour patterns to more positive outcomes.

No description available.

Tang Angie. / Thesis submitted in: November 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 151-172). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / Abstract in Chinese --- p.vi / Table of Contents --- p.vii / List of Publications --- p.xi / Awards --- p.xii / List of Abbreviations --- p.xiii / List of Tables --- p.xv / List of Figures --- p.xvi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Literature Review --- p.3 / Chapter 2.1 --- Gastric cancer-overview --- p.3 / Chapter 2.1.1 --- Epidemology --- p.3 / Chapter 2.1.2 --- Pathology --- p.3 / Chapter 2.1.3 --- Etiologies and Risk Factors --- p.4 / Chapter I. --- Environmental factors --- p.4 / Chapter a. --- Helicobacter pylori infections --- p.4 / Chapter b. --- Epstein-Barr virus (EBV) --- p.6 / Chapter c. --- Dietary factors --- p.6 / Chapter d. --- Smoking --- p.6 / Chapter II. --- Genetic Factors --- p.7 / Chapter a. --- Hereditary Gastric Cancer --- p.7 / Chapter b. --- Genetic polymorphism --- p.8 / Chapter III. --- Cyclooxygenases (COX) enzymes --- p.10 / Chapter IV. --- Molecular carcinogenesis --- p.11 / Chapter a. --- Activation of proto-oncogenes --- p.11 / Chapter b. --- Candidate tumor suppressor genes --- p.12 / Chapter 1. --- Gene mutation and deletion --- p.12 / Chapter 2. --- Epigenetic Silencing --- p.13 / Chapter 2.2 --- Epigenetics --- p.14 / Chapter 2.2.1 --- DNA methylation --- p.15 / Chapter 2.2.2 --- Histone modification --- p.28 / Chapter I. --- Histone acetylation and deacetylation --- p.32 / Chapter II. --- Histone methylation --- p.32 / Chapter III. --- Histone phosphorylation --- p.34 / Chapter IV. --- Histone ubiquitylation --- p.34 / Chapter 2.3 --- "HAT, HDAC and HDAC inhibitors" --- p.36 / Chapter 2.3.1 --- HAT --- p.38 / Chapter 2.3.2 --- HDAC --- p.39 / Chapter (a) --- Class I --- p.40 / Chapter (b) --- Class II --- p.41 / Chapter (c) --- Class III --- p.42 / Chapter (d) --- Mammalian HDAC and their mechanism of deacetylation --- p.44 / Chapter 2.3.3 --- HDAC inhibitors --- p.45 / Chapter I. --- Class I/II natural inhibitors --- p.47 / Chapter II. --- Class I/II synthetic inhibitors --- p.48 / Chapter III. --- Sirtuins inhibitors --- p.49 / Chapter IV. --- Activity of HDAC inhibitors in vitro --- p.50 / Chapter a. --- Effect in the gene expression --- p.50 / Chapter b. --- Non-transcriptional effects --- p.55 / Chapter c. --- Activity of HDAC inhibitors with other agents --- p.57 / Chapter d. --- Effects in xenograft tumor models --- p.57 / Chapter V. --- Clinical trials of HDAC inhibitors --- p.59 / Chapter Chapter 3 --- Aims of the study --- p.63 / Chapter Chapter 4 --- Materials and Methods --- p.64 / Chapter 4.1 --- Cell culture --- p.64 / Chapter 4.2 --- Drug treatment --- p.64 / Chapter 4.2.1 --- Suberoylanilide Hydroxamic Acid treatment --- p.64 / Chapter 4.2.2 --- Trichostatin A treatment --- p.65 / Chapter 4.3 --- Cell proliferation assay --- p.66 / Chapter 4.4 --- Apoptotic assay --- p.67 / Chapter 4.5 --- Flow cytometry --- p.67 / Chapter 4.5.1 --- Cell preparation --- p.67 / Chapter 4.5.2 --- Propidium Iodide staining --- p.68 / Chapter 4.5.3 --- Annexin V-FITC staining --- p.68 / Chapter 4.5.4 --- Flow cytometer analysis --- p.69 / Chapter 4.6 --- Total RNA extraction --- p.70 / Chapter 4.7 --- DNA extraction --- p.71 / Chapter 4.8 --- Protein extraction --- p.72 / Chapter 4.9 --- Western blottng --- p.72 / Chapter 4.10 --- Microarray analysis --- p.74 / Chapter 4.10.1 --- Sample preparation for microarray --- p.74 / Chapter 4.10.2 --- Hybridization --- p.75 / Chapter 4.10.3 --- Scanning and data processing --- p.75 / Chapter 4.10.4 --- Data analysis --- p.76 / Chapter 4.11 --- Primer design --- p.77 / Chapter 4.12 --- RT-PCR --- p.77 / Chapter 4.12.1 --- Reverse transcription --- p.77 / Chapter 4.12.2 --- Quantitative RT-PCR --- p.78 / Chapter 4.13 --- Methlyation study --- p.79 / Chapter 4.13.1 --- Demethylation by 5-aza-2'deoxycytidine --- p.79 / Chapter 4.13.2 --- Bisulfite modification --- p.79 / Chapter 4.13.3 --- Methylation-specific PCR (MSP) --- p.79 / Chapter Chapter 5 --- Results --- p.81 / Chapter 5.1 --- Morphological changes in AGS cells --- p.81 / Chapter 5.2 --- Anti-cancer effects of HDAC inhibitors --- p.81 / Chapter 5.2.1 --- Effect of HDAC inhibitors on cell growth --- p.81 / Chapter a. --- SAHA inhibits cell proliferation --- p.82 / Chapter b. --- TSA inhibits cell proliferation --- p.82 / Chapter 5.2.2 --- Cell cycle analysis --- p.87 / Chapter a. --- Effect of SAHA on cell cycle --- p.87 / Chapter b. --- Effect of TSA on cell cycle --- p.88 / Chapter 5.2.3 --- Induction of apoptosis on AGS cells --- p.92 / Chapter a. --- SAHA induces apoptotic cell death --- p.92 / Chapter b. --- TSA induces apoptotic cell death --- p.94 / Chapter 5.3 --- Induction of histone expression on AGS cells --- p.102 / Chapter 5.3.1 --- HDAC inhibitors induced acetylation of histone H3 --- p.102 / Chapter 5.3.2 --- HDAC inhibitors induced acetylation of histone H4 --- p.103 / Chapter 5.4 --- SAHA- and TSA-induced gene expression profiles --- p.106 / Chapter 5.5 --- Verification of gene expression by quantitative RT-PCR --- p.108 / Chapter 5.6 --- Methylation study --- p.113 / Chapter Chapter 6 --- Discussion --- p.116 / Chapter 6.1 --- Improved treatment strategy is needed for gastric cancer. --- p.116 / Chapter 6.2 --- HDAC inhibitors as potential anti-cancer agents --- p.117 / Chapter 6.3 --- Potential anti-cancer effect of TSA and SAHA on AGS cells --- p.120 / Chapter I. --- Morphological changes of AGS gastric cancer cells --- p.120 / Chapter II. --- Inhibition of cell proliferation --- p.120 / Chapter III. --- Induction of cell cycle arrest --- p.121 / Chapter IV. --- Induction of apoptosis --- p.122 / Chapter 6.4 --- Expression of acetylated histones upon treatment with TSA and SAHA --- p.124 / Chapter 6.5 --- Identify potential target genes upon treatment with TSA and SAHA --- p.125 / Chapter 6.5.1 --- Candidate genes involved in cell cycle --- p.126 / Chapter a. --- P21WAF1 --- p.126 / Chapter b. --- p27kip1. --- p.128 / Chapter c. --- Cyclin E & Cyclin A --- p.128 / Chapter d. --- Signal-induced proliferation-associated gene 1 (SIPA1) .… --- p.129 / Chapter 6.5.2 --- Candidate genes involved in apoptosis and anti-proliferation --- p.130 / Chapter a. --- BCL2-interacting killer (apoptosis-inducing) (BIK) (Pro-apoptotic gene) --- p.131 / Chapter b. --- Thioredoxin interacting protein (TXNIP) (Proapoptotic gene) / Chapter c. --- Cell death-inducing DFFA-like effector b (CIDEB) (apoptosis induction) --- p.132 / Chapter d. --- B-cell translocation gene 1 (BTG1) - (anti-proliferation) --- p.133 / Chapter e. --- Quiescin 6 (QSCN6) (anti-proliferation) --- p.133 / Chapter f. --- "Cysteine-rich, angiogenic inducer, 61 (CYR61) (anti-proliferative)" --- p.134 / Chapter g. --- Metallothionein 2A (MT2A) (apoptosis induction and anti-proliferative) --- p.134 / Chapter 6.5.3 --- Other genes reported to be up-regulated with HDAC inhibitors treatment --- p.135 / Chapter a. --- Glia maturation factor-gamma (GMFG) --- p.135 / Chapter b. --- v-fos FBJ murine osteosarcoma viral oncogene homolog (FOS) / Chapter c. --- Interleukin 8 (IL-8) --- p.136 / Chapter d. --- Insulin-like growth factor binding protein- 2 (IGFBP2) --- p.137 / Chapter e. --- Integrin alpha chain 7 (ITGA7) --- p.138 / Chapter 6.5.4 --- Selected highly up-regulated genes with HDAC inhibitors treatment --- p.139 / Chapter a. --- Aldo-keto reductase family 1，member C3 (AKR1C3) --- p.139 / Chapter b. --- GPI-anchored metastasis-associated protein homolog (C4.4A) --- p.139 / Chapter c. --- "Serine (or cysteine) proteinase inhibitor，clade I (neuroserpin), member 1 (SERPINI1)" --- p.140 / Chapter d. --- "Serine (or cysteine) proteinase inhibitor，clade E (nexin, plasminogen activator inhibitor type 1), member 1 (SERPINE1)" --- p.140 / Chapter e. --- Adrenomedullin (ADM) --- p.141 / Chapter f. --- Dehydrogenase/reductase (SDR family) member 2 (HEP27) --- p.142 / Chapter g. --- Cholecystokinin (CCK) --- p.142 / Chapter h. --- Silver homolog (mouse) (SILV) --- p.143 / Chapter 6.6 --- Genes regulated by gene promoter hypermethylation in AGS cells --- p.143 / Chapter Chapter 7 --- Conclusion --- p.147 / Chapter Chapter 8 --- Further Studies --- p.150 / References --- p.151 / Appendix I --- p.151 / Appendix II --- p.III / Appendix III --- p.IV / Appendix IV --- p.VI

A current initiative to eliminate lymphatic filariasis (LF), headed by the World Health Organization, aims to interrupt transmission of the disease through yearly community-wide treatment with the broad spectrum anthelmintic albendazole (ABZ), in combination with ivermectin (IVM) or diethylcarbamazine (DEC). Over the years, the use of both ABZ and IVM in the treatment of veterinary parasites has led to widespread anthelmintic resistance against these drugs. In this study, we genotyped microfilaria of Wuchereria bancrofti, a causative agent of LF, in order to detect the presence of mutations which confer ABZ resistance in other parasites, and we identified such mutations in worms obtained from untreated patients in Ghana and Burkina Faso, West Africa. Microfilaria from patients who had been treated with ABZ + IVM, had a significantly higher frequency of the resistant genotype, and this frequency was even higher in worms from patients that had received two rounds of treatment. In addition, the untreated population of microfilaria had an excess of homozygotes in the population. This excess homozygosity was equivalent to a Wright's Inbreeding Statistic of FIT= 0.44, and we found that the population was significantly subdivided between patients. In order to better understand the mechanisms and factors involved in the potential spread of ABZ resistance, caused by such mutations, through a population of Culex-transmitted W. bancrofti, we developed a deterministic model that incorporates genotype structure into the epidemiological model EPIFIL. This model predicts that the combination of ABZ + DEC leads to stronger selection for the resistant genotype than ABZ + IVM, and that drug efficacy assumptions are an important factor affecting the spread of drug resistance. Treatment coverage, non-random mating, initial allele frequency and number of treatments also had substantial impact on the speed and magnitude of the spread of ABZ resistance. When we expanded this model to include potential IVM-resistance alleles we found that, under ABZ + IVM treatment, selection for resistance to either drug is enhanced by the presence of resistance against the second drug. Similarly, excess homozygosity caused by parasite non-random mating may increase selection for a dominant IVM resistance allele through enhancing the spread of a recessive ABZ resistance allele. Resistence developed more slowly when it was inherited as a polygenic trait. Results from this study suggest that resistance monitoring is crucial, as resistance may not be apparent until treatment is stopped, recrudescence occurs and treatment is reapplied.

[Truncated abstract] In the last ten years regulator T (Tr) cells have re-emerged as an integral part of the immune system. Research in this field has rapidly demonstrated the role of these cells in the maintenance of immune homeostasis and their involvement in disease. Tr cells are generated in the thymus as a normal part of the developing immune system. Furthermore, antigen-specific Tr cells are induced in the periphery by a mechanism which is yet to be completely elucidated, but is likely to involve dendritic cells. Tr cells play an important role in autoimmune disease, transplantation tolerance, cancer. Most recently Tr cell involvement has been demonstrated in a growing number of infectious diseases. Tr cell induction was reported in Friend Virus infection at the commencement of this study, and subsequent to publication of our findings have also been identified in FIV and HIV. Murine AIDS (MAIDS) is a fatal chronic retroviral infection induced in susceptible strains of mice by infection with BM5d, a replication defective virus, in a viral mixture which is designated LP-BM5. The manipulation of Tr cells detailed in this thesis and the related publication represent the first reported therapy utilising targeted removal of Tr cells. Chapter 1 summarises the literature relevant to this study up to November 2004. Chapter 2 details the materials and methodologies used in this work. Chapter 3 investigates whether Tr cells are involved in the development of murine AIDS, particularly in the early stages of infection. The data presented in this chapter provides evidence of a population of CD4+ Tr cells which express CD25 on their cell surface and secrete TGF-β, some IL-10 and low levels of IL-4 are induced following infection with LP-BM5. These cells were found to arise by day 12 post infection (pi) by flow cytometry and immunosuppressive cytokine expression was found to peak at day 16 pi indicating a role in the early stages of disease progression. Chapter 4 investigates the effect of therapeutically targeting these induced Tr cells using the antimitotic agent Vinblastine during their induction period. The efficacy of treatment was found to be time dependent and was shown to abrogate disease progression maximally when given at day 14 pi. Treatment with anti-CD4 monoclonal antibody was also found to be efficacious at day 14 pi and confirmed the identity of the Tr cells as being CD4+ T cells. Adoptive transfer studies demonstrated that the return of these cells to a successfully treated host results in renewed MAIDS progression, confirming their role in disease progression