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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.
21

Development of Split-protein Systems for Interrogating Biomacromolecules

Shen, Shengyi January 2013 (has links)
The specific interactions of macromolecules along with the activity of enzymes are central to all aspects of biology. It is well recognized that when the relative concentration or activity of macromolecules is perturbed, it can lead to human diseases. Thus, the development of simple methods for the detection of macromolecules and the activity of enzymes in complex environments is important for understanding biology. Moreover, the development of methods for measuring interactions allows for the testing of inhibitors that can be used as tools or drugs for improving human health. Towards this goal, a promising new method has been developed, which is the focus of this thesis, called split-protein reassembly or protein fragment complementation. In this method, a protein reporter, such as the green fluorescent protein or firefly luciferase, is dissected into two fragments, which are attached to designed adaptor proteins. The designed split-protein systems only produce a measurable signal, either fluorescence or luminescence, when a specific macromolecular interaction or activity is present. In this thesis, I have extended previous research on the direct detection of DNA using split-protein sensors utilizing a red fluorescent protein, dsRED from Discosoma that allows for multiplexed DNA detection. I have designed a new split-luciferase based sensor for detection of poly (ADP-ribose) or PAR, which plays a key role in the response to DNA damage and have applied it for monitoring the activity of poly (ADP-ribose) glycohydrolase that controls PAR levels in the cell. Furthermore, I have significantly expanded upon a three-hybrid split-luciferase system for identifying protein kinase inhibitors. I have designed and tested two orthogonal peptide based chemical inducers of dimerization based on BAD and p53mt conjugates. I have studied these chemically induced dimerization systems in detail in order to begin to provide a theoretical basis for the observed experimental results. Finally, in a less related area, I have developed methods for producing water soluble semiconductor nanoparticles called Quantum Dots (QDs), with potential application in biological imaging. I have developed methods for functionalizing the QDs with orthogonal peptides, which can be potentially used for the assembly of high affinity non-covalent QD targeted proteins.
22

Cyclosporin A-induced gingival overgrowth in renal transplant patients : a clinical, histological and experimental study /

Wondimu, Biniyam, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
23

Estudo dos efeitos da geléia real e da proteína MRJP3 em modelos de colite induzida por TNBS e DSS / Study of the effects of royal jelly and protein MRJP3 models of colitis induced by TNBS and DSS

Manzo, Luis Paulo Bognoni, 1981- 21 August 2018 (has links)
Orientadores: Alba Regina Monteiro Souza Brito, Anderson Luiz Ferreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T14:15:42Z (GMT). No. of bitstreams: 1 Manzo_LuisPauloBognoni_M.pdf: 4711838 bytes, checksum: 0267d7f30b132c874529cd6a03786252 (MD5) Previous issue date: 2012 / Resumo: A retocolite Ulcerativa Inespecífica e a Doença de Chron são as principais doenças inflamatórias intestinais. Apesar dos crescentes esforços, não se sabe ainda suas causas. Os tratamentos ainda não são eficazes, as drogas atuais são eficazes na indução da remissão mas não determinam sua cura. Os efeitos colaterais são severos, o que acarreta em baixa adesão ao tratamento. Os produtos naturais tem sido fonte de compostos usados por todo o mundo em diferentes áreas da medicina e ciência. O tratamento oral com geléia real na dose de 100 mg/Kg mostrou-se capaz de aumentar os níveis de grupamentos sulfídrica (GSH) e também a atividade da enzima glutationa peroxidase (GSH-Px) em camundongos com colite induzida por TNBS. A expressão de COX-2 e NF-kB também foram diminuídos, tais resultados demonstram efeitos antioxidantes e antiinflamatórios da geléia real nesta dose neste modelo de colite experimental. O Tratamento intrarretal com a proteína MRJP3 (50 ?g/animal) foi capaz de diminuir os níveis de IL-1? no cólon dos camundongos Balb/c submetidos a colite induzida por DSS. Uma vez que os níveis de IL-6 e IL-10 não foram alterados pelo tratamento intrarretal com MRJP3 50 ?g/animal, podemos afirmar que a proteína não atua pela via da IL-10. Estes efeitos antioxidantes e anti-inflamatórios observados durante o desenvolvimento da colite induzida por TNBS e por DSS em camundongos, podem ser de significativa importância pois abrem portas e encorajam novas pesquisas com a geléia real e sua respectiva proteína MRJP3, motivando novos estudos acerca de outos agentes antioxidantes e outros mediadores anti-inflamatórios envolvidos nestes modelos de colite experimental / Abstract: Ulcerative Colitis and Chron's Disease are the two major forms of IBD. Despite all efforts, these complications of the GTI are still lacking an effective therapy for their cure. Side effects, high cost and low adhesion to treatment are among the negative aspects. Natural products have been a source of widely used compounds in distinct areas of medicine and research. Royal Jelly (RJ) 100 mg/Kg was capable of augmenting the levels of glutathione (GSH) and the activity of glutathione peroxidase (GSH-Px) in mice undergoing TNBS-induced colitis. Furthermore, COX-2 and NF-kB had their expression decreased by the oral administration of RJ 100 mg/Kg. Intra-rectal MRJP3 treatment (50 ?g/animal) was capable of decreasing the levels of IL-1? in mice undergoing DSS-induced colitis, whereas the levels of IL-10 and IL-6 were not altered by MRJP3 50 ?g instillation, what indicates that this decrease is not IL-10-induced. The antioxidant and anti-inflammatory effects observed during the development of DSS and TNBS-induced colitis in mice, may be of crucial importance, since they open and encourage new studies focused on this nourishing substance, especially in experimental models of colitis / Mestrado / Farmacologia / Mestre em Farmacologia
24

Level crossing analysis of chemically induced dynamic nuclear polarization: Towards a common description of liquid-state and solid-state cases

Sosnovsky, Denis V., Jeschke, Gunnar, Matysik, Jörg, Vieth, Hans-Martin, Ivanov, Konstantin L. 08 August 2018 (has links)
Chemically Induced Dynamic Nuclear Polarization (CIDNP) is an efficient method of creating non-equilibrium polarization of nuclear spins by using chemical reactions, which have radical pairs as intermediates. The CIDNP effect originates from (i) electron spin-selective recombination of radical pairs and (ii) the dependence of the inter-system crossing rate in radical pairs on the state of magnetic nuclei. The CIDNP effect can be investigated by using Nuclear Magnetic Resonance (NMR) methods. The gain from CIDNP is then two-fold: it allows one to obtain considerable amplification of NMR signals; in addition, it provides a very useful tool for investigating elusive radicals and radical pairs. While the mechanisms of the CIDNP effect in liquids are well established and understood, detailed analysis of solid-state CIDNP mechanisms still remains challenging; likewise a common theoretical frame for the description of CIDNP in both solids and liquids is missing. Difficulties in understanding the spin dynamics that lead to the CIDNP effect in the solid-state case are caused by the anisotropy of spin interactions, which increase the complexity of spin evolution. In this work, we propose to analyze CIDNP in terms of level crossing phenomena, namely, to attribute features in the CIDNP magnetic field dependence to Level Crossings (LCs) and Level Anti-Crossings (LACs) in a radical pair. This approach allows one to describe liquid-state CIDNP; the same holds for the solid-state case where anisotropic interactions play a significant role in CIDNP formation. In solids, features arise predominantly from LACs, since in most cases anisotropic couplings result in perturbations, which turn LCs into LACs. We have interpreted the CIDNP mechanisms in terms of the LC/LAC concept. This consideration allows one to find analytical expressions for a wide magnetic field range, where several different mechanisms are operative; furthermore, the LAC description gives a way to determine CIDNP sign rules. Thus, LCs/LACs provide a consistent description of CIDNP in both liquids and solids with the prospect of exploiting it for the analysis of short-lived radicals and for optimizing the polarization level.
25

The genetic susceptibility/resistance to fluorosis among different inbred mouse strains

McHenry, Melissa A.K., 1971- January 2003 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Fluoridation of community water supplies for the purpose of preventing dental caries remains one of the top 10 public health interventions of the last century. However, exposure (ingestion) of greater than optimal amounts of fluoride from a variety of sources has led to an increase in the prevalence of dental fluorosis. We propose that dental fluorosis represents a complex condition caused by environmental and genetic factors. Purpose: To assess the role of genetics in the pathogenesis of dental fluorosis using genetically separate inbred strains of mice. Methods: Twelve genealogically disparate strains of mice were treated with 0 ppm, 25 ppm, and 50 ppm of fluoride in their drinking water. Each mouse was given weekly dental fluorosis evaluations. After 60 days of treatment, femurs were collected for fluoride analysis. Mandibular incisors were isolated for quantitative light induced fluorescence (QLF) studies and fluoride analysis. Digital and 35 mm images were taken of all mouse incisors in order to apply and compare the Dean's Index and the modified Thylstrup and Fejerskov Index (TFI), both indices of dental fluorosis. Skeletal radiographs were taken on the euthanized mice and later examined for extra skeletal calcifications and other gross bony deformities. Results: Differences in dental fluorosis susceptibility/resistance were identified between the strains, ranging from mild, moderate, to severe dental fluorosis. Furthermore, we found clustering of strains into distinct phenotypic groups. The A/J mouse strain was highly susceptible, with a rapid onset and severe development of dental fluorosis compared with the other strains tested. The 129P3/J mouse strain was least affected with negligible dental fluorosis. From the skeletal radiographs, no gross skeletal lesions or evidence of bone dysplasia were noted. Similar body burden of fluoride, as judged from analysis of mineralized tissues, was seen in all strains despite differences in their predispositions to develop dental fluorosis. Both the Dean's and TF indices are useful for classifying the stage or severity of fluorosis in mice, and there are advantages to the use of digital images over conventional 35 mm slide images. Both indices correlate well with the amount of fluoride exposure during amelogenesis; however, these indices are not promising indicators of fluoride burden during amelogenesis. Conclusions: QLF proved to be an innovative and useful tool for the quantification of dental fluorosis. Furthermore, these observations support the role of a genetic component in the pathogenesis of fluorosis.
26

Pathologic Quiz Case: A 30-Year-Old Man With a White Plaque in the Oral Mucosa. Smokeless Tobacco Keratosis

Sheth, Pragna D., Youngberg, George A. 01 January 2004 (has links)
No description available.
27

Jaundice and Hepatorenal Syndrome Associated With Cytosine Arabinoside

Kirtley, D W., Votaw, M L., Thomas, E 01 March 1990 (has links)
A young man receiving high dose cytosine arabinoside (3g/m2 every 12 hours) for promyelocytic leukemia developed rapidly increasing hyperbilirubinemia and hepatorenal syndrome. The patient had been treated previously with courses of standard dose cytosine arabinoside without hepatic or renal complications. His condition rapidly deteriorated, and he required hemodialysis. The total bilirubin increased to 45.4 mg/dL, but alkaline phosphatase remained normal. Twelve days after starting chemotherapy, the patient died of hepatorenal failure. Liver necropsy revealed mild bile stasis and microvesicular steatosis. We suspect high dose cytosine arabinoside played a major role in causing impairment of bilirubin transport within the hepatocyte in this patient.
28

Topical Absorption of Isopropyl Alcohol Induced Cardiac and Neurologic Deficits in an Adult Female With Intact Skin

Leeper, S C., Almatari, A L., Ingram, J D., Ferslew, K. E. 01 February 2000 (has links)
Topical exposure to isopropyl alcohol has been reported in the literature to be toxic if sufficient isopropyl alcohol is absorbed (1-5). A clinical case is reported where a 48-y-old female presented with multiple unexplained cardiac and neurological deficits. The woman had developed the deficits over a 6-mo period in which she had been soaking towels with isopropyl alcohol and applying then to her skin overnight to ease arm pain she was experiencing. Cessation of the isopropyl alcohol exposure resolved her deficits within 3 d. A controlled repeat dermal exposure to isopropyl alcohol under clinical observation reproduced the deficits noted with corresponding serum and urine concentrations of isopropyl alcohol and acetone. Cessation of topical isopropyl alcohol exposure lead to subsequent resolution of all toxicities.
29

"Análise morfológica e bioquímica da sinóvia de coelhos imunizados com colágeno do tipo V" / Morphological and biochemical analysis of the synovia of rabbits immunized with type V collagen

Ogido, Luciana Tsuzuki Ichicawa 24 June 2005 (has links)
Descrevemos modelo original de sinovite experimental em coelhos imunizados com colágeno V com escasso processo inflamatório, intenso remodelamento matricial e vasculite. Analise morfológica e bioquímica foi realizada em coelhas Nova Zelândia (N=20) imunizadas com colágeno do tipo V, comparadas com controles. Foi observado o aumento dos colágenos I, III e V, oclusão do lúmen vascular e escasso processo inflamatório. A análise bioquímica confirmou a fibrose com aumento da síntese de colágeno. Nós postulamos que as alterações sinoviais descritas neste modelo foram conseqüência das particularidades do colágeno V, que promove manifestações imunológicas e clínicas semelhantes à esclerodermia / We described an original model of experimental synovitis in rabbits immunized with collagen V with scant cellular infiltration, intense matrix remodeling and vasculitis. Morphological and biochemical analysis were realized in New Zealand female rabbits (N=20) immunization with type V collagen, compared with control rabbits. It was observed increase of collagen I, III and V, vascular lumen occlusion and scant inflammatory process. Biochemical analysis confirmed the fibrosis with increased synthesis of collagen. We postulate that synovial changes described in this model are consequence of collagen V particularities, which promotes immunologic and clinical manifestations similar to scleroderma
30

Role of 5-HT₃ and tachykinin NK₁ receptors in drug-induced emesis and associated behaviours in the ferret and suncus murinus.

January 2003 (has links)
Lau Hoi Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 134-157). / Abstracts in English and Chinese. / PUBLICATIONS BASED ON WORK IN THIS THESIS --- p.I / ABSTRACT --- p.II / ACKNOWLEDGEMENTS --- p.VI / TABLE OF CONTENTS --- p.VIII / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- General Introduction --- p.1 / Chapter 1.2 --- Emesis --- p.3 / Chapter 1.2.1 --- Introduction --- p.3 / Chapter 1.2.2 --- Retching & Vomiting --- p.3 / Chapter 1.2.3 --- Nausea --- p.4 / Chapter 1.2.4 --- Motor Components of Emetic Reflex --- p.5 / Chapter 1.2.4.1 --- Pre-ejection Phase --- p.5 / Chapter 1.2.4.2 --- Ejection Phase --- p.5 / Chapter 1.2.4.3 --- Post-ejection Phase --- p.6 / Chapter 1.2.5 --- Components of Emetic Reflex --- p.6 / Chapter 1.2.5.1 --- Area Postrema (AP) --- p.6 / Chapter 1.2.5.2 --- Nucleus Tractus Solitarius (NTS) --- p.7 / Chapter 1.2.5.3 --- Vomiting Centre --- p.8 / Chapter 1.2.5.4 --- Vestibular System --- p.10 / Chapter 1.2.5.5 --- Abdominal Visceral Afferents --- p.10 / Chapter 1.2.5.6 --- Forebrain --- p.11 / Chapter 1.2.6 --- Neurotransmitters & Receptors --- p.12 / Chapter 1.2.7 --- Anti-emetics --- p.13 / Chapter 1.3 --- Models of Nausea --- p.16 / Chapter 1.3.1 --- Introduction --- p.16 / Chapter 1.3.2 --- Conditioned Taste Aversion --- p.18 / Chapter 1.3.3 --- Pica Behaviour --- p.20 / Chapter 1.3.4 --- Studies of the Involvement of Vasopressin --- p.21 / Chapter 1.3.5 --- Tachygastria --- p.24 / Chapter 1.3.6 --- Locomotor Activity --- p.26 / Chapter 1.4 --- Markers of Neuronal Activity --- p.27 / Chapter 1.4.1 --- General Comments --- p.27 / Chapter 1.4.2 --- c-fos Expression as a Marker of Neuronal Activity --- p.28 / Chapter 1.4.2.1 --- What is c-fos? --- p.28 / Chapter 1.4.2.2 --- Regulation of c-fos Expression --- p.30 / Chapter 1.4.2.2.1 --- Calcium Response Element --- p.31 / Chapter 1.4.2.2.2 --- Serum Response Element --- p.32 / Chapter 1.4.2.3 --- Types of Receptors Involved in c-fos Expression --- p.32 / Chapter 1.4.2.4 --- Feasibility of Using c-fos Expression as Marker of Cellular Activity --- p.36 / Chapter 1.4.2.5 --- Identification of Emetic Pathway by c-fos Immunohistochemistry --- p.36 / Chapter 1.5 --- Aims & Objectives --- p.37 / Chapter CHAPTER 2 --- METHODS --- p.42 / Chapter 2.1 --- Animals --- p.42 / Chapter 2.1.1 --- Ferrets --- p.42 / Chapter 2.1.2 --- Suncus murinus --- p.42 / Chapter 2.2 --- Measurement of Animal Behaviour --- p.43 / Chapter 2.2.1 --- Experiment Design --- p.43 / Chapter 2.2.2 --- Recording of Animal Behaviour --- p.43 / Chapter 2.2.3 --- Calibration of Equipment Used to Record Spontaneous Locomotor Activity --- p.44 / Chapter 2.2.4 --- Behaviour Recorded by the Observer --- p.45 / Chapter 2.3 --- Administration of Drugs --- p.46 / Chapter 2.3.1 --- Ferrets --- p.46 / Chapter 2.3.1.1 --- General Comments --- p.46 / Chapter 2.3.1.2 --- Drug Antagonism Studies --- p.47 / Chapter 2.3.2 --- Suncus murinus --- p.47 / Chapter 2.3.2.1 --- General Comments --- p.47 / Chapter 2.3.2.2 --- Dose-Response Studies --- p.48 / Chapter 2.3.2.3 --- Drug Antagonism Studies --- p.48 / Chapter 2.4 --- c-fos Expression Studies in Ferret Brainstems --- p.50 / Chapter 2.4.1 --- Animals and Anaesthesia --- p.50 / Chapter 2.4.2 --- Perfusion and fixation --- p.50 / Chapter 2.4.3 --- Dehydration of brains --- p.51 / Chapter 2.4.4 --- Embedding of tissue --- p.52 / Chapter 2.4.5 --- Sectioning --- p.52 / Chapter 2.4.6 --- Staining --- p.52 / Chapter 2.4.7 --- Antibodies used --- p.55 / Chapter 2.4.8 --- Positive Control Slides --- p.55 / Chapter 2.5 --- Experimental Design and Statistics --- p.56 / Chapter 2.5.1 --- Randomization of Treatments --- p.56 / Chapter 2.5.2 --- Statistics --- p.57 / Chapter 2.5.2.1 --- Ferrets --- p.57 / Chapter 2.5.2.2 --- Suncus murinus --- p.59 / Chapter 2.6 --- Drugs and Chemicals Used --- p.60 / Chapter 2.6.1 --- Drugs Used --- p.60 / Chapter 2.6.2 --- Chemicals Used --- p.62 / Chapter CHAPTER 3 --- RESULTS --- p.63 / Chapter 3.1 --- Ferret --- p.63 / Chapter 3.1.1 --- "The Effect of Ondansetron and CP-99,994 on Emesis and Locomotor Activity Changes Induced by Cisplatin in the Ferret" --- p.63 / Chapter 3.1.2 --- The Effect of Domperidone on Emesis and Locomotor Activity Changes Induced by Apomorphine in the Ferret --- p.69 / Chapter 3.1.3 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Apomorphine in the Ferret" --- p.74 / Chapter 3.1.4 --- c-fos Expression Studies in Ferret Brainstems --- p.79 / Chapter 3.1.4.1 --- Cisplatin-treated Ferrets --- p.79 / Chapter 3.1.4.2 --- Positive Control Slides --- p.84 / Chapter 3.2 --- Suncus murinus --- p.88 / Chapter 3.2.1 --- The Emetic Potential of Nicotine and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.88 / Chapter 3.2.2 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Nicotine in Suncus murinus" --- p.92 / Chapter 3.2.3 --- The Emetic Potential of Copper Sulphate and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.95 / Chapter 3.2.4 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Copper Sulphate in Suncus murinus" --- p.98 / Chapter 3.2.5 --- The Emetic Potential of Cisplatin and its Effects on the Spontaneous Locomotor Activity of Suncus murinus --- p.101 / Chapter 3.2.6 --- The Effect of Ondansetron on Emesis and Locomotor Activity Changes Induced by Cisplatin in Suncus murinus --- p.104 / Chapter 3.2.7 --- "The Effect of CP-99,994 on Emesis and Locomotor Activity Changes Induced by Cisplatin in Suncus murinus" --- p.107 / Chapter 3.2.8 --- "The Effects of Ondansetron and CP-99,994 on Locomotor Activity in Suncus murinus" --- p.110 / Chapter CHAPTER 4 --- DISCUSSION --- p.113 / Chapter CHAPTER 5 --- GENERAL SUMMARY --- p.130 / REFERENCES --- p.134

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