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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.
311

Studies of p63 and p63 related proteins in patients diagnosed with oral lichen planus

Ebrahimi, Majid January 2007 (has links)
Oral lichen planus (OLP) is a chronic inflammatory disease of the oral mucosa and also one of the more common mucosal conditions mostly affecting middle aged individuals. Even though OLP is well investigated the etiology of this disease is still unknown, even if autoimmunity as a possible etiologic factor has been suggested. WHO classifies OLP as a pre malignant condition but malignant transformation of OLP is a matter of great controversy. The p53 protein is a tumour suppressor with the potential to induce apoptosis or cell cycle arrest of DNA damaged cells. Another member of the p53 family, p63, comprises six different isoforms, and plays a crucial role in the formation of oral mucosa, salivary glands, teeth and skin. p63 has also been suggested to be involved in development of squamous cell carcinoma of the head and neck (SCCHN). β-catenin, E-cadherin and epidermal growth factor receptor (EGFR) are p63 related proteins and abnormalities in their expression are suggested to be involved in development of SCCHN. Methods. Using immunohistochemistry and antibodies directed against p53 and those distinguishing between the p63 isoforms we analysed biopsies of OLP, SCCHN and normal oral tissue. We also mapped levels of p63 and p53 isoforms using RT-PCR technique. Furthermore expression of the p63 related proteins β-catenin, E-cadherin and EGFR was studied using immunoblot analysis. In an attempt to investigate autoimmunity as a causative factor of OLP we analysed sera from patients diagnosed with OLP and matched control individuals in order to see if there were autoantibodies directed against the p53 family. Results. When mapping p53 and p63 protein status decreased expression of p63 and increased expression of p53 was seen in OLP compared to normal tissue. In accordance with these results, levels of p63 RNA were also lower in OLP lesions compared with normal tissue. Concerning p53 isoforms, the “original” p53 isoform was expressed in all OLP lesions and normal control tissue. Of the other isoforms, p53β and Δ133p53 were expressed in the majority of samples. Our results regarding p63 related proteins showed a generally lower expression of these proteins in OLP lesions compared to normal control tissue. When studying sera from patients with OLP we found circulating autoantibodies against all six p63 and four p73 isoforms in two patients. Conclusions. The potential for malignant transformation of OLP is still a subject of discussion and rather controversial. While some of our results regarding status of p53 and p63 both at protein and RNA levels support this theory, other results concerning for example p63 related proteins point in the opposite direction. Based on our studies it is thus not possible to either support nor contradict the statement that OLP is a clear-cut premalignant condition. In our effort to understand the etiology of OLP we were the first to demonstrate autoantibodies against p63 and p73 in what could be a subgroup of OLP patients. OLP could thus be suggested to be not one distinct disease, but based on our data a disease comprising different subgroups.
312

The role of interleukin-8 as a neutrophil chemoattractant In bovine <i>pneumonic pasteurellosis</i>

Caswell, Jeffrey Llewellyn 01 January 1999 (has links)
The role of interleukin-8 (IL-8) as a neutrophil chemoattractant in bovine pneumonic pasteurellosis was investigated by characterizing: (1) the expression of IL-8 in the lesions of pneumonic pasteurellosis, (2) the ' in vitro' and 'in vivo' effects of recombinant bovine IL-8 on neutrophil chemotaxis, and (3) the importance of IL-8 as a neutrophil chemoattractant in this disease. The expression of IL-8 in bovine pneumonic pasteurellosis was assessed by Northern analysis, 'in situ' hybridization and enzyme-linked immunosorbent assay. The expression of IL-8 mRNA was elevated dramatically in lesional lung compared to non-lesional lung, viral pneumonia, and normal lung. 'In situ' hybridization revealed intense IL-8 mRNA expression in alveolar macrophages and neutrophils, and milder expression in several other cell types. Bronchoalveolar lavage (BAL) fluid from lesional lung contained 16.06 ± 4.00 ng/ml IL-8, but lower levels were present in non-lesional lung, viral pneumonia, and normal lung (mean ± SEM). Recombinant bovine IL-8 (rbIL-8) was produced using a pGEX expression system. The rbIL-8 induced <i>in vitro</i> chemotaxis and shape change of bovine neutrophils at doses as low as 6.3 ng/ml. After injection of 1.0 ng to 3.3 <math> <f> <g>m</g></f> </math>g of rbIL-8 into bovine skin, neutrophils marginated in vessels within 15 minutes and infiltrated the dermis by 1 hour after injection. These results demonstrate that bovine IL-8 is a neutrophil chemoattractant 'in vitro ' and 'in vivo', at levels equivalent to those present in pneumonic pasteurellosis. An ovine model of pneumonic pasteurellosis was developed to ascertain the effects of <i> in vivo</i> neutralization of IL-8 on the development of disease. At 0, 3, 8 and 20 hours after bacterial infection (p.i.), BAL fluid samples contained 6.5 ± 2.4, 110 ± 48, 554 ± 118, and 507 ± 70 ng/ml IL-8, respectively. Neutrophil infiltration was mild at 3 hours p.i. but progressively more intense at 8 and 20 hours p.i. Lambs were treated intravenously with up to 80 mg of an IL-8-neutralizing antibody prior to bacterial challenge. The antibody treatment failed to completely neutralize IL-8 activity, probably because the levels of IL-8 in the lung were unexpectedly high. The contribution of IL-8 to the neutrophil chemotactic activity of BAL fluid from cattle and lambs with pneumonic pasteurellosis was assessed. Pre-treatment of pneumonic BAL fluid samples with a neutralizing antibody to IL-8, compared to pretreatment with a control antibody, reduced the 'in vitro' neutrophil chemotactic activity significantly, by 15-63% in 9/10 samples. An extract of pneumonic bovine lung induced vigorous neutrophil infiltration following injection into bovine skin, and depletion of IL-8 from the extract reduced this neutrophil influx by 60%. These data indicate that IL-8 is an important neutrophil chemoattractant in both early and well-developed lesions of pneumonic pasteurellosis, but that mediators with actions redundant to those of IL-8 must also be present at these times.
313

Non-Target Effect of Imidacloprid on the Predatory Arthropod Guild on Eastern Hemlock, Tsuga canadensis (L.) Carriere, in the Southern Appalachians

Hakeem, Abdul 01 May 2008 (has links)
Imidacloprid, a neonicotinoid insecticide, is commonly applied on eastern hemlock to reduce populations of Hemlock woolly adelgid (HWA). A large number of other herbivorous and transient insects also are associated with eastern hemlock. These herbivorous insects may acquire imidacloprid through feeding on treated plants. Predatory insects may acquire imidacloprid when they feed on insecticide-contaminated prey. To investigate this phenomenon, a study was conducted at Indian Boundary Campground, Cherokee National Forest, 2005-2007. This study was conducted to: 1) ascertain the effect of imidacloprid used against HWA on the predatory guild associated with eastern hemlock, 2) determine seasonal abundance of the predatory guild on eastern hemlock, and 3) assess influence of vertical stratification on spiders and other predators.During this study, 4,917 predators representing 75 families and 10 orders were collected. Spiders were the most dominant predator group, and the most abundant spider families were Mimetidae (1,038), Salticidae (736), Araneidae (733), Gnaphosidae (517), Philodromidae (330), Theridiidae (168), Tetragnathidae (161) and Thomisidae (142). The most abundant insect predator families were Vespidae (132), Ichneumonidae (50), Braconidae (31), Pentatomidae (25), Reduviidae (24), Coccinellidae (15), and Elateridae (15). Predator densities were not significantly different between pesticide application times (Fall and Spring). In both years, predator densities in control treatments and horticultural oil treatments were significantly (p<0.05) greater than those in imidacloprid treatments. However, predator densities were not significantly (p<0.05) different among soil drench, soil injection, and tree injection treatments or between control and horticultural oil treatments. Predator densities were at least 1.5-3X greater in the imidacloprid-treated plots in 2007 than in 2006, possibly suggesting a rebound in predator densities 1-1½ years after treatment.Predator densities were significantly (p<0.05) greater in the top and middle canopy than in the lower canopy. Imidacloprid concentration level declined progressively from the bottom stratum to the top stratum of the tree canopy. Highest levels were observed in the bottom stratum which shows that higher concentrations of imidacloprid lead to lower numbers of predators and lower concentrations of imidacloprid lead to higher numbers of predators.
314

Protein based methods for the identification and classification of mitochondrial disorders /

Hanson, Bonnie Jean, January 2001 (has links)
Thesis (Ph. D.)--University of Oregon, 2001. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 96-103). Also available for download via the World Wide Web; free to University of Oregon users.
315

Personalbibliographie von Professoren und Dozenten der Pathologie und Pädiatrie an der Universität Erlangen-Nürnberg im ungefähren Zeitraum von 1928-1967; mit kurzen biographischen Angaben und Überblick über die Hauptarbeitsgebiete

Reichel, Magdalena, January 1900 (has links)
Inaug.-Diss.--Universität Erlangen-Nürnberg, Erlangen. / Vita.
316

Diet, nutrition, and activity at Khirbat al-Mudayna inferring health in an historical Bedouin sample /

Sadvari, Joshua W., January 2009 (has links)
Thesis (M.A.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 54-58).
317

Study of the (+)-Pisatin Biosynthetic Pathway by RNAi and Development of a Novel Method to Elicit the Production of Plant Secondary Metabolites

Kaimoyo, Evans January 2005 (has links)
(+)-Pisatin, ([+]-[6aR,11aR]-6a-hydroxy-3-methoxy-8,9-methylenedioxypterocarpan) is the major phytoalexin of the garden pea (Pisum sativum L.). Despite being the first phytoalexin to be chemically characterized, its biosynthesis remains to be fully elucidated. RNA-mediated genetic interference (RNAi) was used to gain further insights into the (+)-pisatin biosynthetic pathway. The expression of three genes, isoflavone reductase (IFR) catalyzing the reduction of 7,2'-dihydroxy-4',5'-methylenedioxyisoflavone to (-)-sophorol, sophorol reductase (SOR) involved in reducing (-)-sophorol to (-)-7,2'-dihydroxy-4',5'-methylenedioxyisoflavanol and hydroxymaackiain-3-O methyltransferase (HMM) involved in methylation of (+)-6a-hydroxymaackiain to (+)-pisatin was silenced. The genes are transcriptionally co-regulated during (+)-pisatin biosynthesis, with the IFR and SOR proposed to function upstream of the HMM gene.Hairy roots expressing the HMM RNAi construct, deficient in (+)-pisatin biosynthesis were identified. However, these did not accumulate (+)-6a-hydroxymaackiain, precursor to (+)-pisatin. Instead they accumulated 2,7,4'-trihydroxyisoflavanone, daidzein, liquiritigenin and isoformononetin. The amino acid sequence of HMM is very similar to that of another methyltransferase, hydroxyisoflavanone-4'-O-methyltransferase (HI4MOT), found in most legumes. HI4?MOT catalyzes the methylation of 2,7,4'-trihydroxyisoflavanone (THI) to 2,7-dihydroxy-4'-methoxyisoflavanone, one of the earliest enzymatic steps in isoflavonoid biosynthesis. In pea, HI4OMT may be the same enzyme as "HMM" catalyzing the methylation of both THI and (+)-6a-hydroxymaackiain. Preventing the methylation of THI could divert pea intermediates to the production of daidzein and isoformononetin instead of (+)-pisatin.None of the transgenic hairy roots expressing the IFR RNAi construct were totally deficient in (+)-pisatin biosynthesis. However, all produced reduced amounts of (+)-pisatin, with one culture accumulating 7,2'-dihydroxy-4',5'-methylenedioxyisoflavone, the substrate for IFR. Hairy roots expressing the SOR RNAi construct deficient in (+)-pisatin biosynthesis were identified. These accumulated (-)-sophorol, the substrate for SOR. These data provide evidence for the involvement of these genes and the intermediates with (-)-optical activity in (+)-pisatin biosynthesis.The elicitation of the biosynthesis of secondary metabolites in plant cell and tissue cultures by electric current was explored. Electric current was demonstrated to elicit the biosynthesis of secondary metabolites in pea hairy and intact roots, seedling, root and cell suspension cultures of various plant species. Electric current has potential for use as an elicitor of secondary metabolites in basic and commercial research ventures.
318

the Nature of Plant Resistance to Obligate Parasites.

Samborski, D.J. January 1955 (has links)
The nature of host susceptibility to phytopathogenic parasites, especially the obligates, remains one of the major problems in plant pathology even though it has been investigated extensively from the early part of the present century until the late thirties. Studies on the genetics of the pathogens and breeding for resistant varieties have predominated since that time. There is at present a revival of interest in the physiology of disease resistance. [...]
319

the Physiology of Verticillium Wilt of Tomato and Potato.

Campbell, J. Ewen. January 1961 (has links)
Verticillium wilt is often the cause of serious losses in potatoes in Eastern Canada and Northern United States. It is of minor importance in field tomatoes except in California and Utah. The disease is not uncommon in greenhouse tomatoes in North America and in Europe. [...]
320

Studies on verticillium wilt of forage legumes.

Aubé, Claude. January 1963 (has links)
Hay is the most important crop in Quebec. According to the annual report of the Quebec Bureau of Statistics for 1961, of a total cultivated area of 7,864,176 acres in Quebec, 3,458,000 acres were in hay. The value of the hay crop in 1961 was 55.8 percent of the value of all field crops in the province. Since alfalfa, birdsfoot trefoil, red, alsike, and ladino clovers are cominant in this hay crop, their agricultural importance is apparent. This, together with the fact that some of these forage legumes, mainly red clover and alfalfa, are the most common rotation crops, led to the choice of these plants for study.

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