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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.
31

Imaging Chronic Pain and Inflammation : Positron Emission Tomography Studies of Whiplash Associated Disorder

Linnman, Clas January 2008 (has links)
This thesis is on chronic neck pain after a rear impact car injury, so called whiplash associated disorder (WAD). Three empirical studies using positron emission tomography (PET) with different radioligands have been performed. The first study evaluated resting state regional cerebral blood flow (rCBF) in WAD patients and in healthy, pain-free controls, by use of oxygen-15 labeled water. Patients had heightened resting rCBF bilaterally in the posterior parahippocampal and the posterior cingulate gyri, in the right thalamus and in the right medial prefrontal gyrus. Attenuated tempero-occipital blood flow was also observed in the patient group as compared to healthy controls. Alterations in rCBF were related to patients’ neck disability ratings. Study I suggests an involvement of the posterior cingulate, the parahippocampal and the medial prefrontal gyri in WAD. This altered resting state neural activity may be linked to an increased self-relevant evaluation of pain and stress. The second study evaluated central expression of the neurokinin-1 (NK1) receptor in WAD patients and healthy controls. Using a carbon-11 labeled specific NK1 antagonist, the receptor availability was measured. Patients displayed lowered NK1 receptor availability in the insula, anterior cingulate, frontal lobe, hippocampus, amygdala and in the periaqueductal gray matter, consistent with results from animal models of chronic pain. NK1 receptor availability was most reduced in the ventromedial orbitofrontal cortex, where attenuations were linearly related to patients fear and avoidance of movement. Thirdly, carbon-11 labeled D-deprenyl was used to investigate the presence of locally inflamed soft tissue in the cervical neck in WAD patients. Although the retention mechanism of [11C]D-deprenyl is not known, the results suggest that WAD patients have chronic inflammatory processes in the neck, most commonly in the adipose tissue at the spineous process of the second vertebra. In summary, this thesis provides evidence for altered central blood flow and receptor characteristics in WAD patients. Further, WAD patients may also have signs of persistent peripheral tissue damage. Both central and peripheral pain mechanisms have been demonstrated and visualized in patients with whiplash associated disorder.
32

PART I. DESIGN AND SYNTHESIS OF BICYCLIC INTERNAL BETA-TURN MIMETICS AND THEIR INCORPORATION INTO BIOLOGICALLY ACTIVE LIGANDS; PART II. SYNTHESIS OF CYCLIC PEPTIDES BY RING

Min, Byoung Joon January 2010 (has links)
beta-Turns in many biologically active peptides are important secondary structural elements which are critical for their biological activities. Hence, it is not surprising that beta-turn based pharmacophore design including beta-turn mimetics has become a central topic in medicinal chemistry in addition to alpha-helix or helical peptides. One of the advantages of such beta-turn mimetics is that they can better control torsion angles of the backbone of peptides and to some degree dihedral angles chi (X). These beta-turn mimicking scaffolds are designed to have a higher avidity for the acceptor by overcoming what otherwise is the inherent entropic cost paid for beta-turn formation upon binding to the acceptor. Among different synthetic strategies to bicyclic structures as beta-turn mimetics, consecutive formation of bicyclic structures using tandem acid-catalyzed N-acyliminium ion cyclization is attractive since this methodology was well established in the synthesis of natural product alkaloids. 1,3,6,8-Substituted tetrahydro-2H-pyrazino[1,2-a]pyrimidine-4,7-diones were designed and synthesized as internal beta-turn mimetics through an acid-catalyzed tandem acyliminium ion cyclization. Its development and synthesis are decribed in Chapter 2 to Chapter 4. Its application toward the development and synthesis of a small molecule ligand for melanocortin receptors is described in Chapter 5. In addition, the development of peptidomimetics for opioid receptors is explained in Chapter 6. On the other hand, a dicarba analogue having opioid receptor agonist, and dicarba analogues for MCRs were synthesized through solid phase synthesis including a ring closing metathesis reaction using Grubbs' catalyst (I) in Chapter 8.
33

Understanding the Role of Predictive, Diagnostic and Pathogenic Autoantibodies in Systemic Lupus Erythematosus and its Central Nervous System (CNS) Involvement

January 2011 (has links)
abstract: Systemic lupus erytematosus (SLE) is an autoimmune disease where the immune system is reactive to self antigens resulting in manifestations like glomerulonephritis and arthritis. The immune system also affects the central nervous system (known as CNS-SLE) leading to neuropsychiatric manifestations such as depression, cognitive impairment, psychosis and seizures. A subset of pathogenic brain-reactive autoantibodies (BRAA) is hypothesized to bind to integral membrane brain proteins, affecting their function, leading to CNS-SLE. I have tested this BRAA hypothesis, using our lupus-mouse model the MRL/lpr mice, and have found it to be a reasonable explanation for some of the manifestations of CNS-SLE. Even when the MRL/lpr had a reduced autoimmune phenotype, their low BRAA sera levels correlated with CNS involvement. The correlation existed between BRAA levels to integral membrane protein and depressive-like behavior. These results were the first to show a correlation between behavioral changes and BRAA levels from brain membrane antigen as oppose to cultured neuronal cells. More accurate means of predicting and diagnosing lupus and CNS-SLE is necessary. Using microarray technology I was able to determine peptide sets that could be predictive and diagnostic of lupus and each specific CNS manifestation. To knowledge no test currently exists that can effectively diagnose lupus and distinguish between each CNS manifestations. Using the peptide sets, I was able to determine possible natural protein biomarkers for each set as well as for five monoclonal BRAA from one MRL/lpr. These biomarkers can provide specific targets for therapy depending on the manifestation. It was necessary to investigate how these BRAA enter the brain. I hypothesized that substance P plays a role in altering the blood-brain barrier (BBB) allowing these BRAA to enter and affect brain function, when bound to its neurokinin-1 receptor (NK-1R). Western blotting results revealed an increase in the levels of NK-1R in the brain of the MRL/lpr compared to the MRL/mp. These MRL/lpr with increased levels of both NK-1R and BRAA displayed CNS dysfunction. Together, these results demonstrate that NK-1R may play a role in CNS manifestations. Overall, the research conducted here, add to the role that BRAA are playing in CNS-lupus. / Dissertation/Thesis / Ph.D. Molecular and Cellular Biology 2011
34

Modulation par le récepteur neurokinine-1du mécanisme d’action des immunosuppresseurs chez les cellules T.

Jizi, Khadije 08 1900 (has links)
Le récepteur neurokinine 1 (NK1R) est impliqué dans la régulation des réponses immunitaires innées et adaptatives. Cependant, les mécanismes par lesquels le NK1R modulerait ces réponses ne sont pas connus. Chez les cellules T, les voies de la calcineurine et de la mTOR constituent les cibles d’immunosuppresseurs, comme la cyclosporine A (CsA), le tacrolimus et la rapamycine. Ainsi, nous avons voulu déterminer si le NK1R pourrait agir sur ces voies et si le blocage pharmacologique du NK1R avec des antagonistes sélectifs, pourrait augmenter l’action de ces immunosuppresseurs sur l’activation des cellules T. Tout d’abord, nos résultats ont montré que les cellules Jurkat (celules T humaines) exprimaient à la fois le gène du NK1R et de son ligand (les endokinines). Ceci suggère l'existence d'une régulation autocrine tachykinergique de la fonction des cellules T. Cette hypothèse est appuyée par nos données, où nous avons observé que le blocage du NK1R avec des antagonistes spécifiques (L-733,060 et L-703,606) chez les cellules Jurkat, inhibe la production d'IL-2 et diminue l'activation du NFAT (substrat de la calcineurine). De façon intéressante, nous avons montré un effet de combinaison entre les antagonistes du NK1R et les inhibiteurs de la calcineurine (CsA et tacrolimus) sur la production d’IL-2 et l’activation du NFAT. En revanche, le blocage du NK1R n'a pas d'effet inhibiteur sur l’activation de la mTOR et la p70S6K, mais réduit la phosphorylation de S6R (Ser235/236) et Akt (Ser473). Enfin, nous n’avons observé aucun effet de combinaison avec la rapamycine et l’antagoniste NK1R sur l’activation de mTOR et de sa voie de signalisation. L’ensemble de nos résultats, démontrent la présence d'un nouveau mécanisme de régulation de NFAT impliquant le système tachykinergique NK1R/endokinines chez les cellules T. Par conséquent, nous suggérons que la combinaison des antagonistes NK1R avec les inhibiteurs de la calcineurine pourrait être une alternative thérapeutique intéressante afin de réduire les doses de CsA et le FK506 dans les protocoles de prévention de rejet de greffes. / There are increasing evidences for a role of the neurokinin 1 receptor (NK1R) in the regulation of innate and adaptive immune systems. However, whether NK1R regulates calcineurin/nuclear factor of activated T cell (NFAT) and mTOR pathways in T cells is unknown. These signalling pathways being targets of the immunosuppressive drugs cyclosporine A (CsA), FK506 and rapamycin respectively. We also examined whether pharmacological blockade of NK1R may be combined to those immunosuppressors to repress T cell activation. In this article, we first show that Jurkat T cells express both genes for NK1R and its ligands endokinins which suggests the existence of an autocrine tachykinergic regulation of T cells function. This hypothesis is supported by our data showing that blockade of this receptor with specific NK1R antagonists inhibits IL-2 production in Jurkat T cells which is associated with the reduction of NFAT activation. Interestingly, we show interplay between NK1R antagonists and calcineurin inhibitors to repress IL-2 production and NFAT activation. In contrast, blockade of NK1R has no inhibitory effect on mTOR and p70S6K activation but reduce S6R (Ser235/236) and Akt (Ser473) phosphorylation. However, combining rapamycin with NK1R antagonist has no enhancing effect on rapamycin-reduced mTOR activation and its signalling pathway. Our findings provide the evidence of a novel mechanism of regulation of NFAT activation-induced IL-2 production in T cells involving the tachykinergic system NK1R/endokinins. These observations may offer new application for NK1R antagonists in transplantation immunotherapy in combination with immunosuppressors.
35

Vasomotor symptoms in postmenopausal women : the role of acupuncture and calcitonin gene-related peptide /

Wyon, Yvonne January 2002 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2002. / Härtill 4 uppsatser.
36

Modulation par le récepteur neurokinine-1du mécanisme d’action des immunosuppresseurs chez les cellules T

Jizi, Khadije 08 1900 (has links)
No description available.
37

Substance P affects exclusively on prototypic neurons in mouse globus pallidus / 淡蒼球外節におけるニューロンタイプに依存したサブスタンスP応答 / タンソウキュウ ガイセツ ニオケル ニューロン タイプ ニ イゾン シタ サブスタンス P オウトウ

水谷 和子, Kazuko Mizutani 20 September 2017 (has links)
本研究は、先行研究で示唆されていた淡蒼球外節(GP)におけるニューロキニン1型受容体(NK-1R)の局在を、免疫染色と投射パターン、電気生理学の観点から示した。形態学的には、NK-1Rを持つ細胞がLhx6やPVを共発現し、線条体と視床下核の両方に投射するものの、FoxP2を発現する細胞とは共存しなかった。さらに、パッチクランプを用いてGP細胞の電気的性質を調べた後、NK-1Rアゴニストへの応答を観察した結果を合わせたところ、NK-1R細胞がPrototypicタイプに含まれる特定の集団であることが明らかになった。 / 博士(理学) / Doctor of Philosophy in Science / 同志社大学 / Doshisha University
38

Aprepitanto em estratégia antiemética profilática com dexametasona, ondansetrona e propofol  em pacientes de alto risco para náuseas e vômitos pós-operatórios: estudo duplo-encoberto e aleatorizado / Aprepitant as a fourth antiemetic prophylactic strategy in high-risk patients: a double-blind, randomized trial

Morais, Luciana Chaves de 25 May 2018 (has links)
Introdução: Apesar da abordagem farmacológica multimodal profilática, as náuseas e os vômitos pós-operatórios (NVPO) correspondem a uma das principais queixas dos pacientes após procedimentos laparoscópicos. Em pacientes considerados de alto risco pelo critério de Apfel, a incidência de tais eventos pode chegar a 80%. Neste contexto, os antagonistas dos receptores de NK-1 têm sido recomendados para adultos em adição a outras estratégias antieméticas na tentativa de reduzir essa incidência. Entretanto, o efeito da associação do aprepitanto ao regime dexametasona, ondansetrona e propofol permanece indefinido. Nesta pesquisa, como desfecho principal, estudou-se o efeito da associação do aprepitanto em regime antiemético profilático multimodal para redução de risco de NVPO nas primeiras 24 horas do período pós-operatório em pacientes de alto risco pelo critério de Apfel. Como desfechos secundários, foram estudadas intensidade dos eventos de náuseas, incidência dos eventos de vômitos intensos e ocorrência de consumo de antieméticos de resgate nas primeiras 24 horas do período pós-operatório. Métodos: pacientes adultos, estratificados como alto risco pelo critério de Apfel, submetidos a procedimentos laparoscópicos oncológicos, foram alocados aleatoriamente para receber profilaticamente aprepitanto 80 mg (grupo de tratamento) ou amido (grupo controle) associados à dexametasona (4 mg ou 8 mg), ondansetrona (4 mg ou 8 mg) e anestesia venosa alvo-controlada com propofol. A análise estatística do desfecho principal foi realizada utilizando o Teste Exato de Fisher, e a hipótese nula foi descartada se p < 0,05. Resultados: Sessenta e seis pacientes concluíram o estudo. NVPO ocorreram em 13 (40,6%) pacientes nas primeiras 24 horas após emergência da anestesia no grupo controle. No grupo tratamento, ocorreram náusea em 5 pacientes (14,7%, p = 0,03) e vômito em 1 paciente (2,9%, p = 0,0002). A redução de risco relativo foi de 63,8% (IC 95% 9,9% - 86%) para náusea e de 92,7% (IC 95% 61,2% - 98,8%) para vômito. Episódios de náusea intensa ocorreram em 2 (6,3%) pacientes e de vômitos intensos, em 4 (12,5%) pacientes, no grupo controle. Um paciente apresentou vômito intenso no grupo tratamento. Em relação ao consumo de antieméticos, 9 (28,1%) pacientes solicitaram medicamentos antieméticos de resgate no grupo controle e 3 (8,8%) pacientes, no grupo tratamento, nas primeiras 24 horas pós-operatórias (p = 0,02). Conclusão: O aprepitanto (80 mg), como uma quarta estratégia antiemética profilática, pode contribuir para a redução significativa de NVPO e de consumo de antieméticos de resgate em pacientes de alto risco / Background: Despite the use of multimodal pharmacological approach, postoperative nausea and vomiting (PONV) is one of the most important causes of patients discomfort after laparoscopic surgeries. NK-1 receptor antagonists have recently being recommended for prophylaxis of PONV in adults, but the combination with serotonin (5-HT3) receptor antagonists such as ondansetron, corticosteroids such as dexamethasone and propofol, are not yet well established. The primary aim of this randomized and double-blind study was to assess whether the addition of aprepitant to a multimodal management strategy for PONV prophylaxis in a high-risk patient population would further decrease the incidence of PONV in the first 24 postoperative hours. The secondary aims were the quantification of nausea intensity, number of episodes of vomiting and rescue antiemetic consumption in the same period. Methods: patients classified as Apfel Score 3 or 4, scheduled to laparoscopic surgeries to treat cancer, were randomized to receive either oral aprepitant 80mg (treatment group) or matching placebo (control group) before induction of anesthesia. All patients received intravenous dexamethasone 4 mg or 8 mg at induction of anesthesia, ondansetron 4 mg or 8 mg at the end of the surgery and a standardized total intravenous anesthesia (TIVA) technique. Statistical analysis was performed using Fisher\'s Exact Test and the null hypothesis was ruled out if p < 0.05. Results: Sixty-six patients completed the study. Nausea and vomiting occurred in 13 (40.6%) patients during the first 24 hours in the control group (all patients who presented nausea also vomited). In the treatment group, nausea occurred in 5 patients (14.7%, P = 0.03) and vomiting occurred in 1 patient (2.9%, P = 0.0002). The reduction in the relative risk was 63.8% (95%CI 9.9% - 86%) for nausea and 92.7% (95%CI 61.2% - 98.8%) for vomiting. Severe nausea occurred in 2 (6.3%) patients, and severe vomiting occurred in 4 (12.5%) patients in the control group. One patient presented with severe vomiting in the treatment group in the first 24 postoperative hours. The administration of rescue antiemetics occurred in 9 (28.1%) patients in the control group and in 3 (8.8%) patients in the treatment group in the first 24 postoperative hours (P = 0.02). Conclusion: Eighty milligrams of aprepitant added to a three-drug multimodal prophylaxis strategy can bring benefits to a high-risk population by reducing PONV episodes and rescue antiemetic requirements
39

Aprepitanto em estratégia antiemética profilática com dexametasona, ondansetrona e propofol  em pacientes de alto risco para náuseas e vômitos pós-operatórios: estudo duplo-encoberto e aleatorizado / Aprepitant as a fourth antiemetic prophylactic strategy in high-risk patients: a double-blind, randomized trial

Luciana Chaves de Morais 25 May 2018 (has links)
Introdução: Apesar da abordagem farmacológica multimodal profilática, as náuseas e os vômitos pós-operatórios (NVPO) correspondem a uma das principais queixas dos pacientes após procedimentos laparoscópicos. Em pacientes considerados de alto risco pelo critério de Apfel, a incidência de tais eventos pode chegar a 80%. Neste contexto, os antagonistas dos receptores de NK-1 têm sido recomendados para adultos em adição a outras estratégias antieméticas na tentativa de reduzir essa incidência. Entretanto, o efeito da associação do aprepitanto ao regime dexametasona, ondansetrona e propofol permanece indefinido. Nesta pesquisa, como desfecho principal, estudou-se o efeito da associação do aprepitanto em regime antiemético profilático multimodal para redução de risco de NVPO nas primeiras 24 horas do período pós-operatório em pacientes de alto risco pelo critério de Apfel. Como desfechos secundários, foram estudadas intensidade dos eventos de náuseas, incidência dos eventos de vômitos intensos e ocorrência de consumo de antieméticos de resgate nas primeiras 24 horas do período pós-operatório. Métodos: pacientes adultos, estratificados como alto risco pelo critério de Apfel, submetidos a procedimentos laparoscópicos oncológicos, foram alocados aleatoriamente para receber profilaticamente aprepitanto 80 mg (grupo de tratamento) ou amido (grupo controle) associados à dexametasona (4 mg ou 8 mg), ondansetrona (4 mg ou 8 mg) e anestesia venosa alvo-controlada com propofol. A análise estatística do desfecho principal foi realizada utilizando o Teste Exato de Fisher, e a hipótese nula foi descartada se p < 0,05. Resultados: Sessenta e seis pacientes concluíram o estudo. NVPO ocorreram em 13 (40,6%) pacientes nas primeiras 24 horas após emergência da anestesia no grupo controle. No grupo tratamento, ocorreram náusea em 5 pacientes (14,7%, p = 0,03) e vômito em 1 paciente (2,9%, p = 0,0002). A redução de risco relativo foi de 63,8% (IC 95% 9,9% - 86%) para náusea e de 92,7% (IC 95% 61,2% - 98,8%) para vômito. Episódios de náusea intensa ocorreram em 2 (6,3%) pacientes e de vômitos intensos, em 4 (12,5%) pacientes, no grupo controle. Um paciente apresentou vômito intenso no grupo tratamento. Em relação ao consumo de antieméticos, 9 (28,1%) pacientes solicitaram medicamentos antieméticos de resgate no grupo controle e 3 (8,8%) pacientes, no grupo tratamento, nas primeiras 24 horas pós-operatórias (p = 0,02). Conclusão: O aprepitanto (80 mg), como uma quarta estratégia antiemética profilática, pode contribuir para a redução significativa de NVPO e de consumo de antieméticos de resgate em pacientes de alto risco / Background: Despite the use of multimodal pharmacological approach, postoperative nausea and vomiting (PONV) is one of the most important causes of patients discomfort after laparoscopic surgeries. NK-1 receptor antagonists have recently being recommended for prophylaxis of PONV in adults, but the combination with serotonin (5-HT3) receptor antagonists such as ondansetron, corticosteroids such as dexamethasone and propofol, are not yet well established. The primary aim of this randomized and double-blind study was to assess whether the addition of aprepitant to a multimodal management strategy for PONV prophylaxis in a high-risk patient population would further decrease the incidence of PONV in the first 24 postoperative hours. The secondary aims were the quantification of nausea intensity, number of episodes of vomiting and rescue antiemetic consumption in the same period. Methods: patients classified as Apfel Score 3 or 4, scheduled to laparoscopic surgeries to treat cancer, were randomized to receive either oral aprepitant 80mg (treatment group) or matching placebo (control group) before induction of anesthesia. All patients received intravenous dexamethasone 4 mg or 8 mg at induction of anesthesia, ondansetron 4 mg or 8 mg at the end of the surgery and a standardized total intravenous anesthesia (TIVA) technique. Statistical analysis was performed using Fisher\'s Exact Test and the null hypothesis was ruled out if p < 0.05. Results: Sixty-six patients completed the study. Nausea and vomiting occurred in 13 (40.6%) patients during the first 24 hours in the control group (all patients who presented nausea also vomited). In the treatment group, nausea occurred in 5 patients (14.7%, P = 0.03) and vomiting occurred in 1 patient (2.9%, P = 0.0002). The reduction in the relative risk was 63.8% (95%CI 9.9% - 86%) for nausea and 92.7% (95%CI 61.2% - 98.8%) for vomiting. Severe nausea occurred in 2 (6.3%) patients, and severe vomiting occurred in 4 (12.5%) patients in the control group. One patient presented with severe vomiting in the treatment group in the first 24 postoperative hours. The administration of rescue antiemetics occurred in 9 (28.1%) patients in the control group and in 3 (8.8%) patients in the treatment group in the first 24 postoperative hours (P = 0.02). Conclusion: Eighty milligrams of aprepitant added to a three-drug multimodal prophylaxis strategy can bring benefits to a high-risk population by reducing PONV episodes and rescue antiemetic requirements
40

Positron Emission Tomography (PET) Studies in Anxiety Disorders

Michelgård Palmquist, Åsa January 2010 (has links)
Anxiety disorders are very common and the primary feature is abnormal or inappropriate anxiety. Fear and anxiety is often mediated by the amygdala, a brain structure rich in substance P (SP) and neurokinin 1 (NK1) receptors. To learn more about how the human amygdala is modulated by fear and anxiety in event-triggered anxiety disorders and to investigate if the SP/NK1 receptor system is affected, regional cerebral blood flow (rCBF) ([15O]-water; Study I and II) and the SP/NK1 receptor system ([11C]GR205171; Study III and IV) were studied with positron emission tomography (PET). In Study I we investigated the neural correlates of affective startle modulation in persons with specific phobia by measuring rCBF during exposure to fearful and non-fearful pictures, paired and unpaired with acoustic startle stimuli. Fear-potentiated startle was associated with activation of the affective part of the anterior cingulate cortex and the left amygdaloid–hippocampal area. In Study II short-term drug treatment effects on rCBF in patients diagnosed with social phobia was evaluated, comparing the NK1 receptor antagonist GR205171 to the selective serotonin reuptake inhibitor citalopram and placebo. Social anxiety and neural activity in the medial temporal lobe including the amygdala was significantly reduced by both drugs but not placebo. In Study III we investigated if activity in the SP/NK1 receptor system in the amygdala would be affected by fear provocation in individuals with specific snake or spider phobia. Fear provocation was associated with a decreased uptake of the NK1 antagonist [11C]GR205171 in the amygdala, possibly explained by an increase in endogenous SP release occupying the NK1 receptors. Study IV was conducted to explore the resting state NK1 receptor availability in PTSD patients as compared to healthy controls. Increased resting state binding of the tracer [11C]GR205171 in the amygdala of patients with PTSD suggested an increased amount of available receptors. In summary, fear and fear-potentiated startle modulates the human amygdala, possibly through the SP/NK1 receptor system.

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