Developing a plant virus-based expression system for the expression of vaccines against Porcine Reproductive and Respiratory Syndrome Virus

Virus-based expression systems have been widely exploited for the production of recombinant proteins in plants during the last three decades. Advances in technology have boosted scale-up manufacturing of plant-made pharmaceuticals to high levels, via the complementation of transient expression and viral vectors. This combination allows proteins of interest to be produced in plants within a matter of days and thus, is well suited for the development of plant-made vaccines or therapeutics against emerging infectious diseases and potential bioterrorism agents. Several plant-based products are currently in varying stages of clinical development. To investigate the viability of virus-based expression systems for plant-made subunit vaccines against Porcine reproductive and respiratory syndrome virus (PRRSV), I have developed several viral vectors which express partial PRRSV glycoprotein 5 (GP5). In this thesis, I demonstrated that viral vectors can increase the expression of proteins for vaccine development in a variety of host plants. Green fluorescent protein (GFP) and the C-terminus of GP5 fused with GFP (GP5C-GFP) were expressed at up to 37.29 mg/kg and 4.36 mg/kg fresh weight of leaf tissue, respectively, in soybean plants via biolistic bombardment, using viral vectors derived from Bean pod mottle virus (BPMV). A Cucumber green mottle mosaic virus (CGMMV)-based vector was employed to display chimeric virus particles, presenting the neutralizing epitope (NE) of GP5, at levels as high as 35.84 mg/kg of cucumber leaf fresh weight, via agroinfiltration. In addition, GFP and the ectodomain of GP5 fused with GFP (GP5e-GFP) were successfully produced at up to 2.03 g/kg and 36.53 mg/kg fresh weight of leaf tissue, respectively, in Nicotiana benthamiana using transient expression of Pepino mosaic virus (PepMV)-based vectors. Co-infiltration of viral vectors with p19, a silencing suppressor, can help to mitigate the toxicity of GP5e to plant tissue and enhance the accumulation of this protein. These plant-made products may be tested as oral subunit vaccines against PRRSV in pigs during future experimental trials. Overall, the results demonstrate that viral systems can produce low-cost, versatile and robust vaccines that have a great impact in the fight against viral diseases, especially in developing countries

すり身加工品で感知される塩味強度とテクスチャーの関係に関する研究

東京海洋大学博士学位論文 平成29年度(2017) 応用生命科学 課程博士 甲第447号指導教員: 岡﨑惠美子東京海洋大学201

An Unconventional Pathway: A Qualitative Inquiry Into the Experience of Racial Minority Transfer Students

Transfer students’ success is increasingly being discussed in higher education. A large population of transfer students includes racial minority, low-income, and first-generation college students. Due to the multiple layers of students’ identities, it has been difficult for educational leaders in institutions to grasp the essential elements needed to serve these students. As a result, this qualitative study contributes to this discussion and efforts to support the transfer student’s success. In this study, qualitative methods, including interviews with 14 students from 4-year universities and community colleges and a survey, were used to identify the steps and resources associated with supporting transfer students. The critical race theory framework served as the central lens to determine how racial factors played a vital key in the students’ post-transfer experience. The goal of this study was to ensure that the transfer students receive the essential resources and guidance from their institutions to have a successful transfer pathway to earning their degree

Towards improved detection, prevention and integrated control of scrub typhus in Central Vietnam

SUMMARY Background Scrub typhus is a zoonotic infectious disease caused by obligate intracellular bacteria Orientia spp, transmitted to humans by the bites of infected larval-stage trombiculid mites, which are found mainly on rodents of forests and rice fields across the Asia-Pacific region. Scrub typhus is a severe public health problem, with one billion people at risk globally, causes illness in an estimated one million people every year, and became a leading cause of treatable non-malarial febrile illness. Case fatality reports vary widely around a median mortality of 6.0% (range 0-70%) for untreated and 1.4% (range 0-33%) for treated scrub typhus patients. In Vietnam, after 40 years of neglect, scrub typhus (ST) is re-emerging as evidenced by expanding geographical distribution and increase in new cases. Unfortunately, both the clinical and laboratory diagnoses of ST remain challenging, even at the national hospital. Due to late diagnosis and late treatment effects, a severe case complication rate of 17% and a mortality rate of 1.2% among 251 infected and diagnosed patients was reported at the national hospital in 2003. Epidemiological and ecological information on scrub typhus is very scant in Vietnam, and there is no updated evidence on practical preventive measures and fostered case-detection. Dengue fever (DF) has made a substantial impact over the two past decades in Vietnam and is unequivocally the leading cause of febrile illness throughout the country. Dengue incidence per 100,000 population has steadily increased from 32.5 in the year 2000 (24,434 cases) to 149.9 in 2018 (141,927 cases), at the third rank among the 28 most common communicable diseases. Because of non-specific symptoms such as high fever, headache, skin rash or myalgia are common to both ST and DF, differential diagnosis is required to decide on the treatment strategies. The overall aim of the present PhD research was to contribute to a better understanding and improving case detection and practical prevention of scrub typhus in Vietnam. Specifically, the work aimed to i) differentiate scrub typhus from dengue fever using admission clinical manifestations and routine blood tests; ii) investigate behavioural and environmental related risk factors of scrub typhus; iii) evaluate temporal dynamics of DNA and serology-based assays and its efficacy in early diagnosis of scrub typhus in Vietnam. Methods First, a study including 221 and 387 confirmed acute cases of ST and DF, respectively, and use of multivariable logistic regression and classification and regression trees (CART), identified clinical and laboratory parameters differentiating ST from DF. Then in 2018/2020, a clinical hospital-based active surveillance study, and a retrospective residence-enrolment date-age-matched case-control study were conducted to investigate the risk factors of ST in Khanh Hoa, Vietnam. Finally, were used data of two hospital active surveillances of suspected ST patients that were done in Khanh Hoa in the periods of 2013-2014 and 2018-2020. The PCR, IgM ELISA, IgM rapid test (RDT) results and days of fever on admission of these patients were used to evaluate temporal dynamics of DNA and serology-based assays and their efficacies in early diagnosis of scrub typhus in Vietnam. Results The main variables to distinguish scrub typhus from dengue included i) the eschar; ii) regional lymphadenopathy; iii) an occupation in nature; iv) increased days of fever on admission; v) increased neutrophil count; vi) decreased ratio of neutrophils/lymphocytes; vii) increased platelet count; and viii) the higher age of patients. Sensitivity and specificity of predictions for scrub typhus based on these seven factors reached 93.7% and 99.5%, respectively, in multi. When excluding the “eschar” variable, the values dropped to 76.3% and 92.3%, respectively. Using the CART model, the corresponding values for the alternative decision tree model were 95.0% and 96.9% when including the variable “eschar” and 77.4% and 90.7% without eschar. Several factors were significantly associated with acquisition of scrub typhus, including sitting/laying directly on the household floor (adjusted OR=4.9, 95%CI:1.6–15.1), household with poor sanitation/conditions (aOR=7.9, 95%CI:1.9–32.9), workplace environment with risk (aOR=3.0, 95%CI:1.2–7.6), observation of mice around the home always (aOR=3.7, 95%CI:1.4–9.9), and use of personal protective equipment in the field (aOR=0.4, 95%CI:0.1–1.1). PCR buffy coat performed best from day 1 to day 6, compared to ELISA and RDT, with an overall positivity rate of 73% during this early phase. ELISA IgM and RDTs performed better after day 7 of fever, with positivity rates of 90% and 81%, respectively, in the later phase – but contributed to diagnosis from day 3 of fever. The combination of PCR buffy coat with an RDT detected 93% to 100% of all positive cases during the first 14 days of fever. Conclusions This work provides evidence for better understanding on fostered case-detection and practical preventive measures of scrub typhus in Vietnam. A combined package with clinical training, risk factors training, and RDTs should be implemented at primary health care level to promote accurate diagnostic for scrub typhus in the hotspot area. The findings from this study are useful for training courses at the community level, support the establishment of preventive measures, create better awareness among the public and inform regional surveillance, and promote much-needed effective public health responses against scrub typhus - this after many decades of neglect in Vietnam

Coordinated failure? a cross-country bank failure prediction model

This paper empirically investigates the causes of bank failures in Japan and Indonesia. Using logistic regression analysis of financial ratios, we explore the usefulness of domestic bank failure prediction models with a cross-country model that allows for cross-correlation of the error terms. Our results suggest that loans, both as a ratio to total assets, deposits and in some cases the ratio of non-performing loans, are the most significant predictors of bank failure in both Japan and Indonesia. Regulatory capital ratios, on the contrary, do not seem to be significant indicators of failure. In addition to the domestic models, we explore the usefulness of a cross-country model of bank failure prediction and find that this model outperforms the domestic models on several diagnostic tests.Bankruptcy; logistic regression; early warning; logit; bank failure; bank crisis

BRAND EXPERIENCE FOR LUXURY CARS: A CASE STUDY OF VIETNAMESE CONSUMERS

This dissertation would not have been possible without the guidance and the help of several individuals who in one way or another contributed and extended their valuable assistance in the preparation and completion of this study. First and foremost, I would like to express my very great appreciation to Dr Sally McKechnie, my research supervisor, for her patient guidance, enthusiastic encouragement, useful critiques and offering suggestions for improvement of this research work. Secondly, I am deeply indebted to the Department of Marketing for providing the valuable knowledge during my study and giving me permission to commence this dissertation. I have furthermore to extend my thanks to the University of Nottingham for their outstanding study environment. Finally, I wish to thank my dearest parents, siblings and friends for their support and encouragement

Towards a Rule-level Verification Framework for Property-Preserving Graph Transformations

International audienceWe report in this paper a method for proving that a graph transformation is property-preserving. Our approach uses a relational representation for graph grammar and a logical representation for graph properties with first-order logic formulas. The presented work consists in identifying the general conditions for a graph grammar to preserve graph properties, in particular structural properties. We aim to implement all the relevant notions of graph grammar in the Isabelle/HOL proof assistant in order to allow a (semi) automatic verification of graph transformation with a reasonable complexity. Given an input graph and a set of graph transformation rules, we can use mathematical induction strategies to verify statically if the transformation preserves a particular property of the initial graph. The main highlight of our approach is that such a verification is done without calculating the resulting graph and thus without using a transformation engine