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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Transformation studies of human t-cell leukemia virus with emphasis on the role of tax and rex

Je, Jianxin, January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xii, 133 p.; also includes graphics. Includes abstract and vita. Advisor:, Dept. of Molecular, Cellular, and Developmental Biology. Includes bibliographical references (p. 108-133).
2

Studies with the human t-cell leukemia virus tax and rex positive trans-regulatory proteins

Anderson, Matthew David, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xv, 129 p.; also includes graphics Includes bibliographical references (p. 105-129). Available online via OhioLINK's ETD Center
3

Studies of deltaretrovirus RNA packaging, infectivity and drug susceptibility

Jewell, Nancy Ann, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiii, 111 p.; also includes graphics Includes bibliographical references (p. 102-111). Available online via OhioLINK's ETD Center
4

Identification and characterization of the post-translational modifications of the HTLV types 1 and 2 regulatory protein Rex

Kesic, Matthew J. January 2009 (has links)
Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes bibliographical references (p. 146-178).
5

Human T cell lymphotropic virus 1 associated infective dermatitis in KwaZulu-Natal, South Africa.

Hlela, Carol. January 2008 (has links)
Background Human T cell Lymphotropic Virus Type I (HTLV-I) associated infective dermatitis, first described by Sweet in Jamaican children, is a pattern of eczema characterized by exudation, crusting around the nostrils, ears and scalp with eventual appearance of a generalized fine papular rash. More recently LeGranade and co-workers have proposed major and minor criteria in establishing the diagnosis of HTLV-I associated infective dermatitis (HAID). HTLV-I has been aetiologically linked to Adult T cell leukaemia/lymphoma (ATLL) and tropical spastic paraparesis (TSP). HAID is not only a marker of childhood infection with HTLV-I but may be a harbinger of more serious HTLV-I associated diseases later on in life such as ATLL or TSP. The pathogenesis of HAID is poorly understood so are the histopathological features of this entity. The effects of co-infection with human immunodeficiency virus- 1 (HIV-1) are inconclusive. HAID is described in Sub Saharan Africa, Senegal but no data is published on this entity in Southern Africa, characterizing the clinical, laboratory features and the histopathology of this entity. Aims and Objectives 1) To describe the clinical and histological features of HTLV-I associated infective dermatitis in KZN, South Africa 2) To determine the virological characteristics of HTLV-I in KZN, South Africa 3) To assess for HTLV-I / HIV co-infection Methods This was a prospective study of all patients with HAID who presented to King Edward VIII hospital (KEH), outpatient department over a period of 42 months. These were patients who fulfilled the clinical criteria of HAID. Enrolled patients were subjected to a confirmatory HTLV-I serology testing. Demographic data was obtained from all HTLV-I seropositive patients. Their clinical examination included dermatological, neurological and pathological examination. A blood count, immunoglobulin levels, serum protein electrophoresis measuring albumin levels and globulin fractions were measured. For bacteriological assessment skin swabs were taken from the affected sites with stool samples examined for parasites, ova and cysts. The HIV-1 status together with HIV-1 viral load were determined on those enrolled. The CD4 count, CD8 counts and CD4/CD8 ratio were also calculated. Skin biopsies were taken for histological examination. PCR for HTLV subtyping was performed on a subset of the cohort. Results Demography Of the 60 patients recruited, 33 fulfilled criteria for HAID. The majority of patients fell between age categories of 6 to lOyears. The male to female ratio was 1:1. There were more females in the adult group than there were within the childhood group. All of the patients in our cohort were African. Clinical features The lesions were erythematous, scaly, exudative, and crusted in all cases. The distribution of lesions was as follows: scalp (77.4%), retroauricular areas (71%), the axilla (65%) and paranasal areas (58%) were the sites more commonly affected. Nasal crusting was not a significant feature in this series. Bacteriology Culture was positive for Staphylococcus aureus (S. aureus) in 90%, with streptococcal group of organisms found in 68% of the skin swabs taken from the lesional skin. Haematological Our patients were mildly anaemic as has been shown in previous studies. They had a mean Hb of 11.5g/dl. In 12 of the 14 patients tested, the erythrocyte sedimentation rate (ESR) was elevated. Serum protein electrophoresis and levels of Immunoglobulin A, G and M were raised. The mean CD4 count in the entire group was elevated at 1730 cells/fil, CD8 was 1299 cells/ul Histopathology The major histological findings were as follows: 38% demonstrated a superficial and deep perivascular inflammatory infiltrate, 28% had a superficial and deep perivascular inflammatory infiltrate together with a lichenoid dermatitis, 12.9% had features of superficial and deep inflammatory infiltrate with an interface dermatitis, 6.4% revealed features of seborrhoeic dermatitis. Genotyping Our patients were infected with the strains belonging to the Cosmopolitan, A Subtype (HTLV-Ia). Complications Complications were low in this series with the commonest being scabies in 6(18.1%), corneal opacities in 3(8.6%), 2(6 %) with HAM/TSP. No parasitic worm infestations were isolated. HIV/HTLV-I co-infection Of the 33 patients, 9 (30 %) were co-infected with HIV. The mean viral load in this group was 52 000 copies/ml. Their mean CD4 count was also elevated at 1505cells/^il with a CD8 of 1704 cells/Mi and a CD4/CD8 ratio of 1.15. Discussion Thirty three of the 60 patients enrolled met the diagnosis for HAID according to the established criteria. The mean age in this series was 17 years (range: 8 months-46 years)however; almost a third (30.3%) were children under 12 years, reinforcing the entity as a childhood infective condition. There was an equal male female distribution in the childhood group and a female predominance in the adult group. Clinically patients presented with infected erythematous, scaly lesions mainly on the scalp, neck and post- auricular area. The clinical features were in keeping with other series worldwide. The complication rate was low in our cohort. S. aureus was the predominant organism in both anterior nares and lesional skin. The most common histological pattern was superficial and deep perivascular inflammatory infiltrate. The subtype in our series was the Cosmopolitan Subtype A (HTLV-Ia) as opposed to subtype B in Japan. We share with Brazil a common subtype. A subset of our patients (30%) was co-infected with HIV. The CD4 cell count in this subgroup was lower than the entire group but this was not statistically significant. The histological patterns found in this subgroup infected with HIV were similar to the rest of the group except for a more intense eosinophilic infiltrate in these skin biopsy specimens. Conclusion HTLV-I associated infective dermatitis is distinct entity which affects the African population of KwaZulu Natal, South Africa. It is predominantly a disease of childhood with an equal female to male ratio in children. The clinical features are an exudative, erythematous scaly rash most commonly found involving the scalp, axillae, paranasal and retroauricular areas. HTLV-I positivity is essential for the diagnosis; the Cosmopolitan Subtype A is commonest in South Africa. The commonest histological pattern is a superficial and deep perivascular infiltrate in 38%. A subset, 30%, was co-infected with HIV. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2008.
6

The FYN-TRAF3IP2 gene fusion drives oncogenic NF-κB signaling in peripheral T cell lymphoma

Kim, Christine Sheila January 2020 (has links)
Angioimmunoblastic T cell lymphoma (AITL) and peripheral T cell lymphoma not-otherwise-specified (PTCL, NOS) have poor prognosis and lack actionable targets for directed therapies in most cases. Here we report the identification of FYN-TRAF3IP2 as a novel highly recurrent oncogenic gene fusion in AITL and PTCL, NOS tumors. Mechanistically, FYN-TRAF3IP2 triggers aberrant NF-κB activity by engaging TRAF6 downstream of T cell receptor signaling. Moreover, FYN-TRAF3IP2 expression in hematopoietic progenitors induces NF-κB-driven T cell transformation in mice and cooperates with loss of the Tet2 tumor suppressor in PTCL development. Therapeutically, abrogation of NF-κB signaling in FYN-TRAF3IP2-induced tumors via IκB kinase inhibitors delivers strong anti-lymphoma effects in vitro and in vivo. These results formally demonstrate an oncogenic role for FYN-TRAF3IP2 and NF-κB signaling in the pathogenesis of PTCL.
7

Seroepidemiology of Plasmodium falciparum, human immunodeficiency virus and human T-cell leukemia virus infections in mothers and their infants in Zimbabwe

Mutambu, Susan L January 1995 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 108-129). / Microfiche. / xi, 129 leaves, bound ill., maps, photos. 29 cm
8

Functional characterization and multi-factor analysis of exhaustion in chronic lymphocytic leukemia T cells

Lee, Joanne Haeun January 2021 (has links)
Adequate cell production for adoptive cell transfer therapies such as Chimeric Antigen Receptor (CAR)-T cell therapy remains a critical barrier to treatment for indications that fail to achieve clinical success. One such disease is Chronic Lymphocytic Leukemia (CLL), a B-cell lymphoma with their characteristically exhausted T cells, marked by a progressive loss of the ability to secrete cytokines and proliferate, as well as an increase in the expression of checkpoint inhibitor molecules such as PD-1. The goal of this thesis is to characterize the functional differences or specific biomarkers within the CLL patient population that is indicative of the proliferation outcomes. Conventional clinical markers such as Rai stage or PD-1 expression alone were inadequate to describe the complex variability among patients. In order to better characterize exhaustion using microscopy-based cell function assays, we developed a sample sparing microscopy chamber that requires as little as 1000 cells per sample. The microscopy chambers were mass produced via injection molding, and made compatible with the antibody microcontact printing technique developed in the Kam lab. The chambers typically reduced cell usage per experiment by 20-fold. This reduction allowed us to measure IL-2 secretion, T cell arrest response to activating antibody patterns (pattern alignment), and motility of scarce human samples simultaneously from a single experiment. Results from these functional readouts along with other clinical markers were used as inputs for a multifactor exploratory analysis to cluster patients according to their functional similarities from the combination of responses in an unbiased manner. The resulting clusters based on the combination of the top 3 parameters IL-2, pattern alignment, and PD-1 resulted in better separation of patient groups and provided a basis for predicting max doubling outcomes from these inputs. We further used motility measurements as a way to understand initial T cell response to activation before the stop response, which was measured as pattern alignment previously. The time it takes for cells to come to a stop at the signal was most informative for translating T cell activation response to a stop response, and eventually to downstream effector functions of cytokine secretion and proliferation. The results of this work provide a powerful framework to describe different donors, and can be applied to cells from additional donors to guide future cell expansion studies.
9

Investigation on the risk of viral infection in musculoskeletal grafts

Yao, Felix Caspar January 2010 (has links)
[Truncated abstract] Around 50,000 hip and knee replacements are performed every year in Australia and this number has been increasing by around 13% annually since 1998 (Transplantation Society 2006). The incidence and number of revision surgery has increased by a similar proportion. Autogenous bone or allograft is still the gold standard grafting material and is currently used in a variety of reconstructive surgical procedures. The use of any allograft material carries with it the risk of transfer of disease from donor to recipient. These tissues can transmit the same viral and bacterial infections as blood, and the products of a single donation may be transplanted to several recipients. In contrast to blood, musculoskeletal tissues may come from surgical and cadaveric donation. Overall, the prevention of infection relies on the maintenance of rigid protocols for procurement, donor and allograft testing, secondary sterilisation, and the adherence to internal safety standards within the tissue banks. This thesis aims to determine the risk of viral infection among musculoskeletal tissue donors in Australia. We retrieved and analysed data retrospectively from three large tissue banks in Australia (Perth, Queensland, Victoria). This includes 12,415 musculoskeletal tissue donors, 10,937 of which are surgical donors and 1,478 of which are deceased donors, for the period of 1993 -2004. This data was analysed to determine the prevalence and incidence of viral infections such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and human T-lymphotropic virus (HTLV) in musculoskeletal allografts. The results indicate that the risk of viral infection from musculoskeletal tissue transplantation in Australia is low. ... The results indicate that the overall prevalence of screened transfusion-transmitted viral infections did not vary significantly for musculoskeletal donors over the study period, despite falling in the general population and first-time blood donors. In tissue donors, HIV incidence significantly decreased over time, and HBV decreased significantly during 1999-2001; however, there was an apparent increase in the estimated incidence of HCV in 2002-2004 compared with earlier years. Furthermore the residual risk estimate of HIV in the period 2002-2004 has declined 5-fold compared to estimates in the period 1993-1995. This is perhaps due to greater awareness of high risk behaviours among donors, improvement in donor recruitment and an overall decrease in infection levels in the general population. Musculoskeletal tissue is second only to blood as the most frequent transplanted human tissue. Viral infection is a potential complication of tissue transplantation. In this thesis the rates of HIV, HBV, HCV and HTV infection in musculoskeletal donors in Australia were identified and then compared with results in published data from Canada, Scotland and the United States. The study also compared that result with first-time blood donors because they have satisfied similar donor selection criteria (Galea et al. 2006). The results indicate that prevalence and incidence estimates for viral infection in Australian tissue donors are higher than those in blood donors. This was also reported in studies from other countries. Accordingly, it is crucial that viral prevalence and incidence be monitored to evaluate the safety of tissue supply and to improve donor selection processes.
10

Evaluation of adherence to antiretroviral therapy using efarivenz as a marker

Tambe, Lisa Arrah Mbang 20 September 2019 (has links)
MSc (Microbiology) / Department of Microbiology / Background: Patients on antiretroviral (ART) are expected to be at least 95% adherent to their treatment, as this will increase their chances of achieving treatment success (maximum and durable suppression of HIV-1 viral load); non-adherence may lead to the development of HIV drug resistance, which may lead to virologic failure and treatment failure. Therapeutic drug monitoring (TDM) has been reported to be the most efficient method to assess treatment adherence in HIV individuals, since it quantifies the concentration of ARTs in biological matrices. This is very effective when using a robust technique such as liquid chromatography tandem mass spectrometry (LCMS/MS), which has played a significant role in the evaluation and interpretation of bioavailability, bioequivalence and pharmacokinetic data. Even with patient adherence, various intra-individual factors have an influence on the expression and function of the genes responsible for the transport (MDR1) and metabolism (CYP2B6) of Efavirenz (EFV). This may lead to single nucleotide polymorphisms (SNPs) in these genes, and this may affect the way antiretrovirals (ARVs) are metabolized. The aim of this study was to evaluate the EFV concentration in plasma to assess patient adherence to treatment and correlate this with genomic occurrences in human and viral genes. Hypothesis: The concentration of ARVs in patient plasma can be used to estimate adherence to treatment; while ARVs’ transport and metabolism can affect bioavailability in a patient’s system. Research Question: Can EFV concentration in plasma be used to estimate patient adherence to treatment? Can transport and metabolism of EFV affect their bioavailability in the patient’s system? Objectives: To determine EFV concentration in plasma to assess patient adherence to treatment and correlate this with genomic occurrences in human genes and viral genes. Methodology: Twenty blood samples were collected from HIV positive individuals before treatment initiation (baseline) and between six to twelve months following treatment initiation (follow-up). The concentration of EFV in patient plasma was measured by LC-MS/MS technique. To infer other factors influencing patient pharmacokinetics output, drug resistance and human genetic characteristics were analyzed. A 1.65kb fragment of the HIV-1 Pol gene was amplified and sequenced to determine drug resistant mutations; while 363bp and 289bp of the MDR-1 and CYP2B6 human genes respectively, were also amplified and sequenced to determine polymorphisms in the transport and metabolism genes. Obtained sequences were manually edited and analyzed using Geneious Version 11.1.5 software. The Stanford HIV Drug Resistance database was used for drug resistant mutation (DRMs) analysis and MDR1 and CYP2B6 test sequences were compared with variant reference sequences to detect the presence of any SNPs. Results: The plasma EFV concentration at baseline and follow-up range was as follows: 0 – 1183ng/ml and below limits of quantification (BLQ) to 15,670ng/ml, respectively. At baseline, 0ng/ml is the expected plasma EFV concentration for patients about to commence treatment; however, two out of twenty patients had 769.9 and 1,183ng/ml drug levels in their system. Post treatment, plasma EFV levels in patients are expected to range from 1,000 – 4,000ng/ml, however, of the twenty patients, two had <1,000ng/ml, and three patients had >4,000ng/ml in their plasma. For Pol amplification, 35% (7/20) were positively amplified at baseline and 25% (5/20) were positively amplified from the follow-ups; 100% (20/20) samples were amplified for both CYP2B6 and MDR1 genes. Detection of drug resistance in the baseline Pol sequences revealed the absence of major mutations in both NRTI and NNRTI drug classes. The G516T polymorphism was present in 15% of the study participants while the homozygous GG and heterozygous GT genotype was present in 25% and 40% of the study participants, respectively. Allele determination was impossible in 20% of the samples, due to the poor nature of the sequence. The homozygous TT variant polymorphism at position 3435 was absent in the entire population, however, the CC and CT genotype was present in 15% and 85% of the study participants respectively. Analysis of EFV concentration in close proximity with the human genetic characteristics reveals that the presence of a Single Nucleotide Polymorphism affects the pharmacokinetic output observed. Discussion and Conclusion: Post treatment, 90% of the study participants indicate adherence to treatment, with only 10% of them having lower than expected EFV concentrations, implying they were non-adherent to their treatment. However, because plasma drug concentrations only reflect a patient’s adherence pattern for a few hours to at most two days, the adherence patterns of these individuals cannot be concluded with certainty. Using plasma EFV as a biomarker to evaluate adherence to treatment in HIV seropositive individuals is a feasible technique, however, its application in non-research settings is still a drawback due to the cost of the method. Characterizing patient inter-individual differences should be taken into consideration, especially since any polymorphism in their transporter and metabolizing genes may influence their overall treatment success. / NRF

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