Dissertations / Theses on the topic 'Shell disease'

The current study investigates the levels of shell disease in Cancer pagurus from various sites on the Gower Peninsula. Generally, it was found that (i) male crabs displayed higher levels of the disease then females, (ii) the proportion of lesioned carapace increased with crab size, (iii) exoskeletal areas subjected to abrasion were most commonly infected and (iv) male crabs from Rhossili were less severely affected than their Langland counterparts. The observed sexual differences in shell disease were attributed largely to behavioural difference whereas, regional (site) differences were explained by variations in substratum type and chitinolytic bacterial populations. Histologically, diseased crabs showed indications of systemic bacterial infections. The thin cuticular lining over the gills appeared to be particularly vulnerable to microbial degradation and penetration. Extensive hepatopancreatic atrophy in severely diseased crabs suggested shell disease is a significant source of crab mortality. Chitinolytic bacteria were isolated from both lesioned and non-lesioned areas of crab exoskeleton. Nine isolates (I1-I9) were partially identified and used for future investigations into the causative agents of the disease. In liquid culture, their extracellular chitinase production/activity was found to vary with chitinous substrate, with C. pagurus shell pieces found to be the strongest inducers of chitinase activity. Zinc and mercury were found to inhibit chitinase activity, whilst iron and copper had the potential to enhance activity. Injections of the bacterial isolates (I4 and I7) into healthy crabs, revealed differential pathogenicities suggesting that shell disease mortalities are highly dependent on the virulence of the exoskeletal penetrator.

>Magister Scientiae - MSc
Tuberculosis (TB) is a disease that results from infection by Mycobacterium tuberculosis, which is regarded the most common infecting organism. TB has killed countless numbers of people particularly in underdeveloped countries. TB bacteria can remain inactive or in dormant state for years without causing symptoms or spreading to other subjects, but as soon as the immune system of the host becomes weakened, the bacteria become active and infect mainly the lungs along with other parts of body. TB cases are further aggravated by other illnesses that affect the immune system, such as human immune virus (HIV), which is very prevalent in resource-poor countries. Interferon-gamma (IFN-γ) is a TB biomarker that has found to have all the qualities that are needed to help and cure Tuberculosis disease. Early diagnosis and treatment are essential measures for effectively controlling the disease. Traditional microbial culture-based tests are the most common methodologies currently used. Usually, these methods involve cell culture, cell counts, and cell enrichment, but this process is time-consuming and laborious, especially for the slow-growing bacteria like M. tuberculosis. Sputum smear is one of the methods currently used to detect acid fast bacilli (AFB) in clinical specimens or fluorescent staining. It is a cost-effective tool for diagnosing patients with TB and to monitor the progress of treatment especially in developing countries. The traditional method of inoculating solid medium such as Lowerstein-Jensen (L-J) or 7H10/7H11 media is also used currently it is slow and takes 6-8 weeks of incubation to diagnose the infection and further more time to determine the susceptibility patterns. The microscopic observation drug susceptibility (MODS) assay they are also used currently they rely on light microscopy to visualize the characteristic cording morphology of M. tuberculosis in liquid culture. MODS has shorter time to culture positivity (average 8 days) compared with LJ medium (average ~26 days), they are very expensive. The Gen-Probe assay specific for M. tuberculosis complex is a rapid detection that is also used, nucleic acid amplification (NAA) test results can be obtained as fast as in two hours (provided if a positive culture is present); it also has a high sensitivity of 99% and specificity of 99.2%. It holds the disadvantage of needing of positive culture that can take several days. Enzyme-linked immunosorbent assay (ELISA), is a test that uses antibodies and colour change to identify a substance. ELISA is an assay that uses a solid-phase enzyme immunoassay (EIA) to detect the presence of a substance, usually an antigen, in a liquid sample or wet sample. It can be used to detection of Mycobacterium antibodies in tuberculosis. The Amplified Mycobacterium Tuberculosis Direct Test (AMTDT) is used for the detection of M. tuberculosis it enables the amplification and detection of M. tuberculosis rRNA directly from respiratory specimens. The diagnostic methods employing genetechnology based on the amplification of DNA or RNA are expected to improve the speed, sensitivity, and specificity of Mycobacterium tuberculosis detection. TB rapid cultivation detection technique, such as MB/BacT system, BactecMGIT 960 system and flow cytometry. The BACTEC MGIT960 system (Becton Dickinson, Sparks, MD) performs incubation and reading of the tubes continuously inside the machine using a predefined algorithm to interpret the fluorescent signal and giving the results as positive or negative. When performing DST, the BACTEC MGIT960 interprets the results as susceptible or resistant to the antibiotic under study. Results are available within 8 days. A recent meta-analysis of the published studies found high accuracy and high predictive values associated with the use of BACTEC MGIT960. These methods are more sensitive and rapid than the traditional microbial culture-based methods. However, they cannot provide the detection results in real-time and most of these methods are centralized in large stationary laboratories because complex instrumentation and highly qualified technical staff are required. Recently, Food and Drug Administration (FDA) approved two new assays that were introduced. These two assays detect in vitro a specific immune response to M. tuberculosis. These tests are the QuantiFERON-TB Gold In-Tube (Cellestis/Qiagen, Carnegie, Australia) and the T-SPOT.TB assay (Oxford Immunotec, Abingdon, United Kingdom). Both assays use whole blood from the patient and measure the production of interferon gamma after the whole blood is exposed to specific antigens from M. tuberculosis. These tests are based on the knowledge that IFN-γ is a product of an active cell-mediated immune response induced by M. tuberculosis. However, TB detection remains a major obstacle due to several drawbacks of these methods. To date, the number of diagnosis approaches for TB has increased as the disease continues to be a major public health problem worldwide and most conventional detection technologies present difficulties in recognizing the presence of M. tuberculosis, since they are time consuming, do not provide clinically reliable results and significantly lack of sensitivity. This thesis focusedon developing two binary and one ternary-electrochemically quantum dots, all synthesised at room temperature in aqueous media for detecting (IFN-γ). Copper telluride (CuTe) and Zinc telluride (ZnTe) was prepared to check how does the two quantum dot behave individual and also to check on how they behave when they are combined and formed ternary quantum dots (CuZnTe). The electrochemical studies of the binary CuTe quantum dots, ZnTe quantum dots and the ternary CuZnTe core-shell quantum dots reveal that ternary quantum dots were stable and showed a significant enhancement in the conductivity of CuZnTe core-shell solution compared to that of CuTe and ZnTe, all studied in solution. The three different quantum dots were capped with three different capping reagents which are tetraethyl orthosilicate (TEOS), thioglycolic acid (TGA), (3-mercaptopropyl) trimethoxysilane (MPS). In the study, a label-free electrochemical immunosensor for the detection of interferon gamma (IFN-γ) was prepared for the first time using ternary quantum dots. The biosensor consists of water-soluble silica coated Copper Zinc telluride (CuZnTe core-shell) quantum dots conjugated to a gold electrode. The antibody-antigen were then conjugated on the CuZnTe core-shell QD modified gold electrode. Results from synthesis of two different binary quantum dots are also presented in the study and compared to the results of the CuZnTe core-shell QDs. The CuTe quantum dots had a small average size which was confirmed through HRTEM, SAXS and XRD analysis

Bacterial shell disease syndrome, which is characterised by the appearance of black spot lesions on the carapace of affected crustacean species, has been found to affect wild populations of the edible crab, Cancer pagurus, in the Gower region, in South Wales. A previous study isolated nine bacterial isolates (11-19) from lesions of diseased edible crabs. The current study further characterises these isolates and possible modes of action. Pathogenicity studies were performed for all isolates by injection into disease-free crabs and from the initial screening of the nine isolates, two (14 and 17) were studied in further detail due to their high pathogenicity towards edible crabs. These isolates were identified as Stenotrophomonas maltophilia (14) and Pseudoalteromonas atlantica (17). Both caused high mortalities upon injection but with distinct modes of action. S. maltophilia appeared to kill crabs by septicaemia, with bacteria being rapidly removed from the haemocoel, only to reappear close to time of death. Studies with P. atlantica showed that this isolate caused crab mortality as a result of the action of toxic extracellular products (ECP). When injected into crabs these were found to produce the same symptoms as live bacteria (e.g. limb tremors followed by paralysis). Due to the nature of the symptoms, which suggested a neurotoxic action, and due to the heat-stability that the ECP showed, LPS was isolated from live P. atlantica bacteria and from ECP. Such preparations when injected into crabs caused high mortalities and similar symptoms as observed following the challenge with live bacteria or ECP. Overall it was concluded that the main virulence factor of P. atlantica for edible crabs is LPS either alone or in combination with other heat-stable factors. Despite these studies, the potential synergistic roles of these and other bacterial isolates in shell disease syndrome is unresolved.

Background: Respiratory diseases are common worldwide, which are caused by various respiratory viruses. As symptoms caused by these viruses are similar, laboratory diagnosis is essential to distinguish the virus. Conventionally, respiratory viruses are isolated by cell culture with a panel of cell lines. However, handling of several cell lines is labour intensive, and the turnaround time of conventional culture is long. In previous study, the use of human colon adeno-carcinoma (Caco-2) in conventional culture was investigated. The study has proven that Caco-2 is generally susceptible to the eight common respiratory viruses, i.e. Adenovirus, Influenza A and B, Respiratory Syncytial virus, Parainfluenza virus 1, 2,3 and 4. As turnaround time of conventional culture is long; therefore, in this study, rapid shell vial culture using Caco-2 cells were evaluated. Moreover, the application of Caco-2 shell vial culture on recovering human metapneumovirus (hMPV) was also investigated. Materials and methods: This study consisted of four stages. First, recovery of viruses by conventional culture and shell vial culture of Caco-2 were compared. Specimens were added to conventional culture and shell vial simultaneously. For conventional culture, formation of CPE was examined daily and IF staining was performed when CPE was indicated; meanwhile, shell vial culture were incubated for seven days and stained with IF to detect infected cells. In stage two, the effect of incubating shell vial culture in rolling drum was investigated. Shell vials inoculated with the same specimen in duplicate were incubated in rolling drum and without rolling drum simultaneously. IF staining was performed in day 2, and results were obtained. For those which are IF negative in day 2, second shell vial was further incubated to seven days before harvest. In the next stage, a large batch of samples was used to evaluate on the use of Caco-2 shell vial culture in day 2 and day 7. Lastly, Caco-2 shell vial and conventional culture and LLC-MK2 conventional culture were tested for isolation of hMPV. Results: Compared to Caco-2 conventional culture, recovery rate of shell vial culture was elevated slightly. When experimenting on the effect of incubation in rolling drum, results showed that recovery rate was raised in shell vial with rolling drum in day 2, moreover, the percentage of positive cells were increased significantly (p value < 0.05). Furthermore, in the evaluation of Caco-2 shell vial in day 2 and day 7, 75% of samples were isolated in day 2 while 85% were recovered in day 7. Lastly, in the investigation on recovery of hMPV, 53%, 42% and 17% hMPV positive cases were isolated by Caco-2 shell vial, Caco-2 conventional culture and LLC-MK2 conventional culture respectively. Conclusion: First, although recovery rate by shell vial and conventional culture were similar, turnaround time was reduced from a week to a few days by shell vial culture. Therefore, Caco-2 shell vial culture is a more efficient than Caco-2 conventional culture in isolating respiratory viruses. The study also showed that incubation of shell vial in rolling drum able to increase the number of positive cells. Furthermore, in this study, Caco-2 cells were also shown to be more efficient in isolating hMPV when compare to LLC-MK2 cells.
published_or_final_version
Microbiology
Master
Master of Medical Sciences

Curcumin, a natural spice of Indian origin is the active principle present in the yellow spice turmeric. However, this molecule is under-utilized due to its poor peroral bioavailability. Very recently, we have demonstrated that encapsulation of curcumin in biodegradable nanoparticles improve oral bioavailability of curcumin. This study reports scale-up and shelf-stability of curcumin encapsulated poly (lactic acid-coglycolic acid) (PLGA) nanoparticles (nCUR). The nCUR were prepared by emulsification solvent evaporation/diffusion method and by varying the process parameters such as homogenisation duration we could successfully prepare large quantities nCUR. The particle size decreased as the homogenisation duration increased from 5 min to 30 min and the particles were spherical. The particle characteristics of large scale preparation (particle size 288.7 ± 3.4 nm and curcumin entrapment efficiency of 52.5 ± 4.3%) were similar to those obtained by lab-scale preparation. The freeze dried nCUR were subjected to six-month ICH shelf-stability conditions suitable for room temperature and refrigerated storage. The nCUR were found to retain the stability over test period as determined by particle characteristics and curcumin integrity using AFM, zeta sizer and XRD analysis. Curcumin has been shown to exhibit various pharmacological actions such as antioxidant, anti-inflammatory, antimicrobial, and anti-carcinogenic activities. Therefore, attempts were made to evaluate the potential of nCUR in models of diabetic cataract, stroke and cancer. In diabetic cataract model, oral administration of 2 mg/day nCUR was significantly more effective than curcumin in delaying cataract progression independent of its glucose lowering ability but with significant effect on aldose reductase pathway reducing sorbitol levels and osmotic pressure. The nCUR was found to be very effective in acute ischemic stroke and the activity was mediated via prevention of oxidative stress, inflammation and MMPs over expression. However, nCUR was not as effective as reported in the literature in ovarian cancer xenograft, but a slight reduction towards 18-19 days post implantion but was not significant. On the other hand, nCUR was ineffective in B16 F0 orthotopic xenograft lung tumour model. Together, this data indicate the potential of curcumin in treating a variety of diseases and nCUR was superior due to its ability to improve peroral bioavailability.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
VÃrios trabalhos tÃm investigado o possÃvel papel protetor da infecÃÃo pelo H. pylori na doenÃa inflamatÃria intestinal (DoenÃa de Crohn e Retocolite ulcerativa), contudo os resultados sÃo controversos. Esse estudo prospectivo, transversal e de carÃter observacional foi realizado entre agosto/2014 e novembro/2016, teve como objetivo avaliar a prevalÃncia do H. pylori e do gene de virulÃncia cagA, nos pacientes portadores de DII e em controles atendidos no ambulatÃrio de Gastrenterologia do Hospital UniversitÃrio da Universidade Federal do Cearà - Fortaleza. Foram analisados 182 pacientes, sendo 41 pacientes com DII nos quais 31,7% (13/41) eram homens e 68,3% (28/41) eram mulheres com idade variando entre 18-72 anos e com 39,84  14,76 (mÃdia  SD) anos; e 141 pacientes dispÃpticos nÃo portadores de DII sendo 39,9% (55/141) homens e 60,1% (86/141) mulheres com idade variando entre 18-70 anos e com 40,1Â14,20 (mÃdiaÂSD) anos, pareados para a idade, os quais assinaram um termo de consentimento livre e esclarecido (TCLE). Todos os pacientes foram submetidos à endoscopia digestiva alta (EDA), sendo coletadas biÃpsias (antro, corpo e incisura). A detecÃÃo de H. pylori foi feita por meio do teste da urease, da anÃlise histolÃgica e da ReaÃÃo em Cadeia da Polimerase (PCR) para o gene ureA. AlÃm disso foi realizado PCR para o gene de virulÃncia cagA. Dos 41 pacientes com DII, 36,5% (15/41) eram portadores da DoenÃa de Crohn e 63,5% (26/41) Retocolite ulcerativa. Sobre os achados endoscÃpicos, os pacientes com DII apresentaram erosÃo gÃstrica em 41,5% (17/41), associada a pangastrite crÃnica encontrada em 64,3,% (9/14) dos pacientes com DoenÃa de Crohn; e 56,5% (13/23) nos pacientes com Retocolite ulcerativa, a inflamaÃÃo ativa e leve foram os achados histopatolÃgicos mais encontrados sendo visualizados em 71,4% (10/14) e 73,9% (17/23); 64,3% (9/14) e 56,5% (13/23) na DoenÃa de Crohn e Retocolite Ulcerativa respectivamente. A bactÃria foi encontrada em 73,2% (30/41) no grupo DII, no grupo controle essa prevalÃncia foi de 75,1% (106/141). Entre os grupos DC e RCU as prevalÃncias do H. pylori foram de 73,3% (11/15) e 73,1% (19/26) respectivamente. O gene cagA foi positivo em 43,9% (15/26) do grupo DII e em 76,3% (80/103) do controle, (p=0.038). A prevalÃncia de H. pylori nos pacientes portadores de DII e controles foi similiar. As cepas cagA foram significantemente menos prevalentes nos pacientes com DII.
VÃrios trabalhos tÃm investigado o possÃvel papel protetor da infecÃÃo pelo H. pylori na doenÃa inflamatÃria intestinal (DoenÃa de Crohn e Retocolite ulcerativa), contudo os resultados sÃo controversos. Esse estudo prospectivo, transversal e de carÃter observacional foi realizado entre agosto/2014 e novembro/2016, teve como objetivo avaliar a prevalÃncia do H. pylori e do gene de virulÃncia cagA, nos pacientes portadores de DII e em controles atendidos no ambulatÃrio de Gastrenterologia do Hospital UniversitÃrio da Universidade Federal do Cearà - Fortaleza. Foram analisados 182 pacientes, sendo 41 pacientes com DII nos quais 31,7% (13/41) eram homens e 68,3% (28/41) eram mulheres com idade variando entre 18-72 anos e com 39,84  14,76 (mÃdia  SD) anos; e 141 pacientes dispÃpticos nÃo portadores de DII sendo 39,9% (55/141) homens e 60,1% (86/141) mulheres com idade variando entre 18-70 anos e com 40,1Â14,20 (mÃdiaÂSD) anos, pareados para a idade, os quais assinaram um termo de consentimento livre e esclarecido (TCLE). Todos os pacientes foram submetidos à endoscopia digestiva alta (EDA), sendo coletadas biÃpsias (antro, corpo e incisura). A detecÃÃo de H. pylori foi feita por meio do teste da urease, da anÃlise histolÃgica e da ReaÃÃo em Cadeia da Polimerase (PCR) para o gene ureA. AlÃm disso foi realizado PCR para o gene de virulÃncia cagA. Dos 41 pacientes com DII, 36,5% (15/41) eram portadores da DoenÃa de Crohn e 63,5% (26/41) Retocolite ulcerativa. Sobre os achados endoscÃpicos, os pacientes com DII apresentaram erosÃo gÃstrica em 41,5% (17/41), associada a pangastrite crÃnica encontrada em 64,3,% (9/14) dos pacientes com DoenÃa de Crohn; e 56,5% (13/23) nos pacientes com Retocolite ulcerativa, a inflamaÃÃo ativa e leve foram os achados histopatolÃgicos mais encontrados sendo visualizados em 71,4% (10/14) e 73,9% (17/23); 64,3% (9/14) e 56,5% (13/23) na DoenÃa de Crohn e Retocolite Ulcerativa respectivamente. A bactÃria foi encontrada em 73,2% (30/41) no grupo DII, no grupo controle essa prevalÃncia foi de 75,1% (106/141). Entre os grupos DC e RCU as prevalÃncias do H. pylori foram de 73,3% (11/15) e 73,1% (19/26) respectivamente. O gene cagA foi positivo em 43,9% (15/26) do grupo DII e em 76,3% (80/103) do controle, (p=0.038). A prevalÃncia de H. pylori nos pacientes portadores de DII e controles foi similiar. As cepas cagA foram significantemente menos prevalentes nos pacientes com DII.

Shell Shock, described as the ‘emblematic psychiatric disorder’ of the First World War has long been synonymous with its soldiers. Its association with close proximity to exploding shells and thus the front lines, leading to the various symptoms of ‘shock’, has both facilitated and ensured its existence throughout the twentieth and twenty first centuries as a masculine affliction. Of the many shell shock studies that have been produced over the last few decades all have focused purely on the experience of the male combatant, predominantly because of this long held preoccupation with ‘front-line’ warfare and its consequences apparently being the preserve of men. Despite the prolonged interest and analysis of shell shock by medical and social historians along with a significant amount of work by feminist and, more recently, revisionist historians, detailing the involvement of women in the First World War, there is stHl no comprehensive study of the psychological problems encountered and suffered by the women who served alongside the British Expeditionary Forces (BEE). However, this study of the roles and duties of a specific group of women, namely nurses, voluntary aid detachments, and ambulance drivers, reveals they frequently endured a variety of traumatic experiences, involving injuries and fatalities, through the vicarious witnessing and dealing with horrific sights and sounds, all compounded by extremes of conditions and privations. Many, if not all, of these factors were given as antecedents for war neurosis in soldiers. Yet, while the nurse has been idolised for her role in the Great War, her experience of psychological ‘breakdown’ has not been examined. This thesis, through the analysis of professional medical literature, of medical case notes, personal testimonies, diaries and autobiographies, is a contribution to the areas of women’s history, medical history and, more specifically, to the history of psychological war trauma. Following a review of the literature in chapter one, chapter two is a re-examination of the proximity of nurses to the fighting zones and therefore of their exposure to danger. Chapter three analyses the nurses’ experience and subsequent symptoms of war trauma, including, importantly, how contemporary medical authorities understood the disorder, and then cared for and managed their female sufferers. These two chapters fundamentally argue that the notion of war-induced traumatic neurosis being the preserve of men is essentially pretence, and that this ‘focus’ on male sufferers means the history of the condition is incomplete. Chapter four essentially examines the issues of repatriation faced by these nurses, specifically examining the evolution of war disability pensions process of which they were excluded until 1920. It also looks at how the nurse, as female war veteran, coped with the consequences of her war experience. In conclusion, this thesis asserts that these nurses did indeed suffer psychologically for their involvement in this war and not because their symptoms and disorders ‘resembled’ those experienced by men, but were in fact, indistinguishable to the extent that some nurses were classed as ‘shellshocked’

Thesis (Ph. D.)--Florida State University, 2004.
Advisor: Dr. Robert H. Reeves, Florida State University, College of Arts and Sciences, Dept. of Biological Science. Title and description from dissertation home page (viewed Sept. 23, 2004). Includes bibliographical references.

An outbreak of a previously unrecorded shell disease in the Portunid mud crab Scylla serrata from Gladstone Harbour, Port Curtis, Queensland, was investigated. The shell lesions called 'rust spots' appeared as orange coloured areas on the dorsal carapace, which in severe cases would ulcerate to expose underlying soft tissues. Through the examination of over 3000 mud crabs the disease prevalence in Port Curtis compared to a number of other locations in Queensland, was determined. Although the prevalence varied over the three successive sampling periods, the average prevalence (14.3%) in Gladstone Harbour was higher than the normal background prevalence of 5% reported for shell disease in other crustacean populations. The lesion pathology of rust spot lesions was determined to be unique compared to the described pathology of other shell diseases, where there is an external erosion of the shell primarily due to pathogenic organisms. In non-perforated rust spot lesions, however, the external shell layers remain intact, with the lesions being restricted to the endocuticle layer and adjacent muscle attachments. As this layer is fonned in the postmoult period, it is likely the lesions are due to a defect in the manufacturing of this layer rather than one of pathogenic degeneration. The histopathology was supported by observations of diseased mud crabs held over a moulting period, in which lesions were also observed to form in the postmoult phase. Although chitinoclastic bacteria are considered to be the primary causative agents of shell disease in other crustaceans, there was no evidence of an infectious or parasitic agent being associated with the internal organs or carapace lesions of the diseased mud crabs examined. Furthermore, water and inoculation transmission experiments failed to reproduce the disease in juvenile mud crabs, sand crabs (Portunus pelagicus) or prawns (Penaeus japonicus). Although the nature of transmission experiments is that failure to reproduce the disease does not necessarily mean definitively a noninfectious cause, in combination with the pathology results they suggest that the cause of rust spot shell lesions is likely to be non-infectious. Haemolympl1. assays were undertaken in an endeavour to measure the health status of diseased mud crabs. Results indicated elevated biochemical factors (two immune factors; antibacterial and phenoloxidase and one cellular enzyme; glutamate dehydrogenase) in both diseased and non-diseased crabs from Gladstone compared to the crabs from Ayr, a non-impacted site where no shell disease had been recorded. Levels in the diseased group of crabs were, however, depressed in comparison to their non-diseased cohorts from the same location, indicating a possible suppression of immune responses in diseased crabs. As shell disease had been associated with polluted environments, the metal analyses of diseased and non-diseased mud crab tissues from Gladstone were also compared with those from Ayr. Copper and zinc were elevated in mud crab hepatopancreas from Gladstone compared to Ayr in two consecutive years. Mean copper concentrations of Gladstone crabs were two to three times greater than for mud crabs sampled from other locations in Queensland. Total metal burdens were also elevated in the Gladstone mud crabs, with a high variation in the diseased mud crabs suggesting that this group may be unable to regulate metal levels. As copper and other metals have been demonstrated to cause inhibition of calcium uptake in other crustaceans, copper exposure experiments were conducted to test the hypothesis that copper could cause rust spot shell lesions by inhibiting calcium uptake in the developing postmoult cuticle. The experiment confirmed that calcium uptake into the carapace of softshelled juvenile, mud crabs was inhibited by sublethal copper exposure. The copper exposure experiments supported the pathology findings that rust spot shell lesions are likely to be caused by a defect in the manufacturing process of the endocuticle. The source of elevated copper accumulations in mud crabs, whether water or sediment borne or dietary was investigated. Water and sediments collected from mud crab burrows and analysed for metals determined that very low concentrations of metals exist in the burrows. A comparison was made between the diets of Gladstone mud crabs and those from Ayr to determine whether diet could be implicated as a source of elevated copper in the Gladstone mud crabs. Stable isotope analyses (carbon and nitrogen) of mud crab muscle was undertaken as an alternative to gut content analysis to determine the dietary sources of carbon and trophic position of crabs from the two areas. Although Gladstone and Ayr crabs had a similar trophic position the disparate delta carbon results suggests the diets of the crabs are different with a correlation established between delta carbon and copper concentration in the tissues. It is possible that diet may be a source of copper in Gladstone mud crabs through biomagnification along the food chain. Although results are preliminary, research into this poorly defined area of ecosystem health in Port Curtis should be continued.

The seeming lack of barriers to gene flow in the northwest Atlantic ocean has led to the general assumption that the population of the American lobster (Homarus americanus) is largely panmictic. However, morphological and genetic data presented in this dissertation suggest that lobster populations are less homogenous than once believed with potential for behavioral barriers to mating and selection of locally adaptive traits. Additionally, both long-term fishing pressures and the recent spread of a destructive epizootic shell disease may have impacted population structure. We developed a novel photographic technique to rapidly collect accurate morphological data with the ability to maintain a database of images for the purposes of re-sampling and testing additional hypotheses. During this study, we found significant morphometric differences between samples of lobsters from collection sites as close as 25km apart. Morphological differences may have originated due to differential selection or plastic responses to environmental variation. To analyze population genetic structure, I surveyed genetic variation using RADseq. Analysis of 1614 putatively neutral SNPs found little genetic difference (Average F¬ST=0.00137) between sample sites suggesting a high level of gene flow between regions. Several additional markers appeared to be under divergent selection between sample sites. A genome scan analysis of both neutral SNPs and SNPs under selection found several selected SNPs associated with principal components of morphological characters. A subsequent BLAST analysis identified a number of the selected SNPs lying in the H. americanus transcriptome, suggesting functional importance. Further experimentation is required to quantify the impacts of plasticity or local adaption in the origin of morphological differences between lobster populations, although the significant differences identified in this research are likely due to a combination of the two. The overarching conclusion is that lobster populations are, in fact, more differentiated than previously predicted and, as such, the findings presented here may have significant management implications.

Disseminated neoplasia (DN) is a proliferative cell disorder that occurs in the circulatory system of bivalves. The condition is progressive and lethal. At least 15 species of bivalves over a wide range of geographic locations have been reported to contract DN. Prevalence levels of disseminated neoplasia can reach up to 90% in some populations. In the laboratory, the condition can be transferred to healthy individuals by injection of hemolymph from animals of the same species with high intensity levels of DN. Studies were conducted to investigate transmission of disseminated neoplasia in the soft shell clam, Mya arenaria. It was determined that soft shell clams from two Oregon bays were susceptible to DN by injection, and that the lack of DN in these west coast populations of soft shell clams was not due to disease resistance in these animals. Additionally, it was demonstrated that onset, development of DN, and survival were directly correlated to the number of neoplastic cells injected into the animal. Experiments investigating water-borne transmission showed that the disease is infectious, and an exposure to DN cell in the hemolymph of highly affected clams was sufficient to cause disease. In a cohabitation study, transmission of DN from one DN positive animal to healthy animals was observed, with specific information collected on the length of exposure and DN intensity of the animals involved. Finally, transmission of disseminated neoplasia was not found to be successful using cell-free filtrates prepared from DN cells and DN positive soft shell clam tissue. A PCR enhanced reverse transcriptase assay was employed, and reverse transcriptase activity was detected in samples prepared from DN positive materials.
Graduation date: 1998

碩士
國立中興大學
獸醫學系
91
Disease is one potential factor of turtle population declining. In this study, our objectives were to understand the causes of diseases, including both infectious and noninfectious diseases, of the pet turtles in the middle of Taiwan. We collected 441 cases from 244 turtles representing eighteen species. A total of 441 clinical and necropsy cases of turtle recorded from October 2001 to April 2003, 18 species were studied in the experiment. Among theses cases, 244 cases with known pathogenic causes and 197 cases of none pathogenic causes. In the first category, the highest isolation is upper respiratory diseases. In the secondary category, the highest isolation is stress syndrown diseases. Most of 441 clinical cases were caused of nutritional imbalance, environmental changing, and stresses. The results showed the diseases of turtles caused with unsuitable of feeding by human. In 1999, the research workers at Endemic Species Research Institute captured 33 turtles, Ocadia sinensis and Trachemys scripta, from the Sun-Moon Lake. All turtles died with shell diseases. Another part of experiment, our objectives were to understand how many turtle with shell diseases in Taiwan and what kind of bacterium from shell lesions. We captured 136 turtles and examined 42 turtles. The incidence of shell lesions was highest in Trachemys scripta with 59 %. Ocadia sinensis had the next frequency of lesions with 41 %. The highest isolation bactera of lesions was Bacillus cereus. The secondary and third were Enterococcus spp. and Vibrio spp.. All of bacterium would make people to fall ill. It is an important problem to be care about the pathogens in the wild turtles.

Title page, summary and table of contents only. The complete thesis in print form is available from the University of Adelaide Library.
"This study examined how the efficacy of 1-MCP varies throughout the year; the effect of concentration, duration and timing of ethylene application; the effect of hand position on the bunch; the timing of 1-MCP application in relation to ripening and harvest time; and the effect of ripening storage temperatures and chilling storage .. The findings of this study allow 1-MCP to be used in a more commercially reliable manner" -- from Abstract.
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Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2006

Human norovirus (HuNoVs) are the most common enteric pathogen around the world that cause ~50% of foodborne illness of disease outbreaks annually. HuNoVs are the member of the Caliciviridae family, which consist of small (38 nm), unenveloped, single stranded RNA (ssRNA) viruses. Norovirus are divided into 5 genogroup (GI, GII, GIII, GIV, GV, GVI and GVII). The GI, GII, and GIV cause human illness, in addition, GII.4 genotype cause the most human disease. Due to HuNoVs are difficult cultured in vitro, the cultivable HuNoVs surrogates have been widely studied. Recently, some studies have been conducted with HuNoVs surrogates, for example bacteriophage MS2. MS2 is conservative surrogate for nonenveloped viruses which there is a close relationship to the behavior of HuNoVs, thus we can examine the infection control measures for HuNoVs. Despite plenty of treatment method been done on testing antiviral effect on bacteriophage MS2, for example UV inactivation, steam ultrasound and antimicrobial etc., plant-based nanoemulsion treatment has yet to be explored. Carvacrol is a major component of oregano essential oil and is responsible for their antimicrobial activity on the growth of various microorganism. In this study, carvacrol nanoemulsions were formed by using the spontaneous emulsification for testing the nanoemulsion stability (14 days shelf life study on its droplet size and particle charge) and antimicrobial activity. In carvacrol nanoemulsion 14 days shelf life test, the droplet size and particle charge stay stable at three different treatment environments (4°C, 20°C and 37°C). The results proved that nanoemulsion (was formed with surfactant agents and medium-chain triglycerides) is stable system that gives consistent droplet size and charge. Although, the low antimicrobial activity was investigated at carvacrol nanoemulsion, the strong antimicrobial effects have been found when carvacrol or carvacrol combined with ionic surfactant of treatment on MS2 and Escherichia coli. Taken together, in the wake of growing consumer demand for different “natural” products in a number of industries, our study broadly informs the development and study of functionalized carvacrol active compound that can not only provide beneficial health for human but can also examine antimicrobial efficacy of control measures for public health.

Σκοπός της παρούσας εργασίας ήταν η δημιουργία ενός ευφυούς συστήματος για τη διάγνωση νοσημάτων του προστάτη αδένα με βάση σημεία και συμπτώματα που διαπιστώνονται σε έναν ασθενή όπως καταγράφονται κατά την κλινική του εξέταση. Τα βασικά σημεία της εργασίας είναι τα εξής: αρχικά παράγεται το μοντέλο της διαγνωστικής στρατηγικής που ακολουθείται για τη διάγνωση των συγκεκριμένων παθήσεων και στη συνέχεια γίνεται εκμαίευση της διαγνωστικής γνώσης από ειδικούς ή/και από εμπειρικά δεδομένα. Η διαδικασία και η γνώση αναπαρίστανται με χρήση υβριδικών μεθόδων αναπαράστασης και με τη χρήση ασάφειας ή/και αβεβαιότητας, η οποία είναι εγγενής σε τέτοια διαγνωστικά συστήματα. Το σύστημα αναπτύχθηκε με τέτοια εργαλεία που δίνουν την δυνατότητα στέγασής του σε ιστότοπο ώστε να χρησιμοποιηθεί ως ειδικός συμβουλευτικός οδηγός από ενδιαφερομένους μη ειδικούς ιατρούς & από ασθενείς καθώς και από φοιτητές υγειονομικών σχολών για εκπαιδευτική χρήση. Το σύστημα περιέχει γνώση εμπειρογνωμόνων σε συνδυασμό με στοιχεία πλούσιας βιβλιογραφικής αναζήτησης και μελέτης. Τέλος πραγματοποιήθηκε επικύρωση των αποτελεσμάτων μέσα από μια τυχαιοποιημένη κλινική έρευνα. Η υλοποίηση του συστήματος μας στηρίζεται σε ένα ειδικό κέλυφος δημιουργίας ευφυών συστημάτων και σε εργαλεία μεθόδων μηχανικής μάθησης. Επίσης, υλοποιούνται δύο εκδοχές (Hirofilos Ι & ΙΙ) και γίνεται σύγκριση των απο-τελεσμάτων. Αναγνωρίστηκε η σαφής υπεροχή του Hirofilos ΙΙ που αναπτυχθηκε με σύστημα μηχανικής εκμάθησης και με δυνατότητα διαχρονικής αναβάθμισης.
During making this project our concern was the creation of a new expert system for diagnosis prostate disease depending on the clinical status of a patient as these are identified during medical examination. The main points were as follows: First has been constructed a diagnosis process model which was followed by the diagnosis for the most common prostate diseases. Secondly was implemented extracting of the medical knowledge based on specialists or/and experimental data. The whole process and the medical Knowledge will be developed using hybrid methods of representation and having the partcipation of such saying fuzziness or inaccuracy, that is innate in that kind of intelligent decision-support. The new intelligent system is already accommodated on a hospital server and is used as a decision-support system, as well as an e-learning platform for medical students. For the implementation of the new system have been used an expert system shell and knowledge engineering tools.