Note: / Clinical chemistry is a medical discipline whose aim is to diagnose and assess disease by analysis of biological specimens. Modem laboratories can perform several hundred different tests using many different methods developed over the last century. The classical, more traditional assays are typically labour-intensive, not multiplexed (only measure one analyte or disorder per assay), expensive, require a long turnaround time, and may not provide adequate sensitivity and specificity. Developments in mass spectrometry (MS) and related technologies over the last two decades have provided solutions for many if not all of these shortcomings. While MS based applications have not yet been widely implemented in clinical chemistry laboratories, current developments will encourage the replacement of traditional methods as well as the expansion of clinically diagnostic endpoints. Indeed, modem MS can be used to simultaneously analyze and quantitate multiple biomarkers in a single analysis. Currently, no other technique exists that can provide a comparable multiplexed analysis. In this thesis, current MS and related technologies were developed and applied to several important but distinct clinical chemistry applications. [...] / La chimie clinique est une discipline medicale qui a pour but de diagnostiquer la presence et la progression d'une maladie par l'analyse d'echantillons biologiques. Les laboratoires modemes peuvent executer des centaines d'analyses en utilisant plusieurs methodes developpees au courrant des cent demieres annees. Les essaisc1assiques, et plus traditionnels, sont souvent laborieux, non multiplexe (mesurent seulement un analyte par essai), cher, exige un long temps de rotation et risque de ne pas fournir une specificite adequate. Pendant les deux dernieres decennies, les developpements dans Ie domaine de la spectrometrie de masse (MS) et les technologies rattachees ont foumi des solutions a plusieurs, pour ne pas dire tous, manques retrouves dans les methodes d'analyse traditionnelles.

Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur.

Diss. (sammanfattning) Umeå : Univ., 2008. / Härtill 4 uppsatser.

Orientador: Sergio de Toledo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-22T13:10:45Z (GMT). No. of bitstreams: 1 Pereira_SergioLuisdaSilva_M.pdf: 4372724 bytes, checksum: d849d535308306a4ec155f540c1f5542 (MD5) Previous issue date: 1997 / Resumo: O objetivo deste trabalho foi avaliar, histológica e radiograficamente, o efeito da calcitonina de salmão sobre a cicatrização de defeitos ósseos circunscritos, criados cirurgicamente em fêmur de coelhos saudáveis. Estes foram divididos aleatoriamente em dois grupos: controle (n=12) e tratado (n=12). O grupo controle não recebeu qualquer substância durante o experimento, enquanto que no grupo tratado foi aplicada dose diária de 2 UI/kg de calcitonina por via intramuscular. Os animais foram sacrificados nos períodos de 7, 14, 21 ou 28 dias após a criação dos defeitos ósseos. As áreas radiolúcidas destes foram medidas, em mm2, através de um programa de computador denominado Auto-Cad, demonstrando que estas, em média, foram menores no grupo tratado, mas estatisticamente significantes apenas nos períodos intermediários de 14 e 21 dias. Histologicamente, aos 7 dias, os defeitos ósseos do grupo tratado apresentaram uma maior neoformação óssea. Aos 28 dias, houve a formação de um osso menos compacto no -grupo controle. No entanto, aos 14 e 21 dias, os resultados foram semelhantes entre os dois grupos. Os resultados obtidos neste trabalho possibilitaram inferir que a calcitonina de salmão acelerou o processo de cicatrização óssea em defeitos circunscritos, baseados nas análises radiográficas e histológicas realizadas / Abstract: The purpose of this study was to evaluate, in healthy animals, the role of salmon calcitonin in the bone healing process of circumscribed bone defects, surgica1ly created, in the twenty-four (24) young adults rabbits femur. Twelve (12) animals were randomized to be the control and test groups (salmon calcitonin - 2 IU/kg during 21 days). The rabbits were sacrificed 7, 14, 21 and 28 days after the surgical procedures. The radiolucids areas of the bone defects was measured, in mm2, by Auto-Cad software. The results showed statistical differences (p<0,05) at 14 and 21 days, favoring the test group. At 7-day, the bone defects of the test group showed more bone regeneration. Nevertheless, at 14 and 21-days, the results was similar among two groups, with the new bone more compact in the test group than control group at 28 days. Thus, this study did demonstrate the positive role of salmon calcitonin in the bone healing process of circumscribed bone defects in healthy rabbits, considering the radioagraphic and histological analysis / Mestrado / Periodontia / Mestre em Clínica Odontológica

Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur.

While much is known about the influence of ventricular afferent neurons on cardiovascular function in the dog, identification of the neurochemicals transmitting cardiac afferent signals to central neurons is lacking. Accordingly, we identified ventricular afferent neurons in canine dorsal root ganglia (DRG) and nodose ganglia by retrograde labeling after injecting horseradish peroxidase (HRP) into the anterior right and left ventricles. Primary antibodies from three host species were used in immunohistochemical experiments to simultaneously evaluate afferent somata for the presence of HRP and markers for two neurotransmitters. Only a small percentage (2%) of afferent somata were labeled with HRP. About half of the HRP-identified ventricular afferent neurons in T3 DRG also stained for substance P (SP), calcitonin gene-related peptide (CGRP), or neuronal nitric oxide synthase (nNOS), either alone or with two markers colocalized. Ventricular afferent neurons and the general population of T3 DRG neurons showed the same labeling profiles; CGRP (alone or colocalized with SP) being the most common (30-40% of ventricular afferent somata in T3 DRG). About 30% of the ventricular afferent neurons in T2 DRG displayed CGRP immunoreactivity and binding of the putative nociceptive marker IB4. Ventricular afferent neurons of the nodose ganglia were distinct from those in the DRG by having smaller size and lacking immunoreactivity for SP, CGRP, and nNOS. These findings suggest that ventricular sensory information is transferred to the central nervous system by relatively small populations of vagal and spinal afferent neurons and that spinal afferents use a variety of neurotransmitters.

Indiana University-Purdue University Indianapolis (IUPUI) / The glial cell line-derived neurotrophic factor (GDNF) family ligands (GFLs) are peptides implicated in the inflammatory response. They are released in increased amounts during inflammation and induce thermal hyperalgesia. Whether these molecules directly affect the sensitivity of primary nociceptive sensory neurons is unknown. This information could provide a link between increased inflammation-induced release of GFLs and their ability to promote inflammatory hyperalgesia. These molecules bind to one of four GFRα receptor subtypes, and this GFL-GFRα complex often translocates to the receptor tyrosine kinase, Ret. The focus of this dissertation was to determine whether GFLs modulate the stimulated-release of calcitonin gene-related peptide (CGRP). Isolated sensory neurons and freshly dissociated spinal cord tissue were used to examine the enhancement in stimulated-release of CGRP, a measure of sensitization. Exposure of isolated sensory neurons to GDNF, neurturin, and artemin, enhanced the capsaicin stimulated-release of immunoreactive CGRP (iCGRP). Sensitization by GFLs occurred in freshly dissociated spinal cord tissue. Persephin, another member of the GFL family, did not enhance stimulated-release of iCGRP. These results demonstrate that specific GFLs are mediators of neuronal sensitivity. The intracellular signaling pathways responsible for this sensitization were also evaluated. Inhibition of the mitogen activated protein kinase (MAPK)/extracellular signal-related kinase 1/2 (Erk 1/2) pathway selectively abolished the enhancement of CGRP release by GDNF. NTN-induced sensitization was abolished by inhibition of the phosphatidylinositol-3-kinase (PI-3K) pathway. Reduction in Ret abolished the GDNF-induced sensitization, but did not fully inhibit NTN or ART-induced sensitization. Inhibition of other cell surface receptors (neural cell adhesion molecule (NCAM), and Integrin β-1) had distinct effects on the sensitization capability of each of the GFLs. Ret and NCAM inhibition in combination abolished ART-induced sensitization. It was necessary to inhibit Ret, NCAM, and Integrin β-1 to prevent the NTN-induced sensitization. These data demonstrate that the GFLs use distinct signaling mechanisms to induce the sensitization of nociceptive sensory neurons. The work presented in this thesis provides the first evidence for these novel and distinct Ret-independent pathways for GFL-induced actions and provides insight into the mechanism of sensory neuronal sensitization in general.

Small cell variant of medullary thyroid carcinoma is an extremely rare histologic entity with a paucity of data. As such, there is a lack of literature and clinical experience regarding this disease. In this report, we examine a case of small cell variant of medullary thyroid carcinoma that presented with intractable nausea, vomiting and diarrhea. While these symptoms were essentially refractory to the standard symptomatic treatment, further laboratory analysis revealed dramatically elevated calcitonin levels and mildly raised thyroid-stimulating hormone levels. Interestingly, repletion of thyroid hormone and treatment with lanreotide resulted in an abatement of our patient's symptoms. This temporal clinical improvement highly suggests a potential role involving thyroid-stimulating hormone and calcitonin levels in the pathogenesis of this disease, and consequently suggests a role for thyroxine in treating the associated gastrointestinal symptoms.

Migraines are a type of headache that specifically act on only one side of the head, although about 30% of patients with migraine may experience a bilateral headache. Migraine is a brain disorders that typically involve issues of the typical sensory processing that takes place in the brainstem. Possible causation has been linked to issues in blood vessels, blood flow, and oxygen levels in the brain. Migraine can be described in three phases, and common throughout the three phases is the importance of the neuropeptide CGRP and its role in migraine pathogenesis. CGRP increases in plasma have been linked to migraine headaches, and specific treatment plans have been tailored to account for this. CGRP is a vasodilator that causes dilation of cranial blood vessels and can lead to possible neurogenic inflammation in the periphery of its release while activating the pain pathway in the brainstem. The primary treatment for migraines is currently drugs from the triptan family and NSAIDs, as well as prophylactic drugs including antiepileptic drugs, beta-blockers, and Ca2+ channel blockers. The experiment conducted for this project aimed to determine the effects of a specific CGRP polyclonal antibody and CGRP receptor antagonist when it is with capsaicin, which stimulates sensory nerves. In an ex-vivo experiment using cell culture medium, the dura mater of mice is given either rabbit polyclonal antibody or a CGRP receptor antagonist or both, and then is challenged with capsaicin. CGRP positive (expressing) fibers and nerve terminals are examined under a fluorescent microscope in the dura mater of the mice.

No description available.