Purpose: To determine whether reduced serum levels of AHSG and elevated levels of BMP-2, 4, 7 are associated with post-arthroplasty HO. Patients: Thirty arthroplasty patients were included, 15 with evidence of peri-articular HO and 15 without (NHO). Methods: Blood samples were collected from all patients ≥ 8 weeks after arthroplasty. Analytes were measured using ELISAs. Mann-Whitney U tests were performed to compare serum analyte concentrations between HO and NHO groups, and between arthroplasty patients and healthy humans. Results: There is no difference in serum concentrations of AHSG, BMP-2, 4, 7 between HO and NHO patients. Arthroplasty patients showed significantly higher BMP-2 and BMP-4 and lower AHSG serum levels compared to healthy humans (p < 0.01). Conclusion: Baseline BMP-2, 4, 7 and AHSG serum levels are not markers of acquired HO. However, elevated baseline levels of BMP- 2, 4 and reduced levels of AHSG appear to be markers of severe inflammatory arthritis.

Purpose: To determine whether reduced serum levels of AHSG and elevated levels of BMP-2, 4, 7 are associated with post-arthroplasty HO. Patients: Thirty arthroplasty patients were included, 15 with evidence of peri-articular HO and 15 without (NHO). Methods: Blood samples were collected from all patients ≥ 8 weeks after arthroplasty. Analytes were measured using ELISAs. Mann-Whitney U tests were performed to compare serum analyte concentrations between HO and NHO groups, and between arthroplasty patients and healthy humans. Results: There is no difference in serum concentrations of AHSG, BMP-2, 4, 7 between HO and NHO patients. Arthroplasty patients showed significantly higher BMP-2 and BMP-4 and lower AHSG serum levels compared to healthy humans (p < 0.01). Conclusion: Baseline BMP-2, 4, 7 and AHSG serum levels are not markers of acquired HO. However, elevated baseline levels of BMP- 2, 4 and reduced levels of AHSG appear to be markers of severe inflammatory arthritis.

Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed Feb. 18, 2009). Includes bibliographical references.

Alpha 2 agonists are frequently used in equine medicine. This study focused primarily on α2 agonist-induced changes in PCV and TSP. A secondary aim of this study was to investigate the effects of α2 agonist on selected serum biochemical parameters and splenic size in order to identify potential causes for the changes seen in PCV and TSP. Four healthy adult mares were treated in a blinded, randomized, cross-over design with a single dose of xylazine (0.5 mg/kg), romifidine (0.04 mg/kg) or detomidine (0.01 mg/kg) intravenously, or detomidine (0.02 mg/kg) intramuscularly. A 1-week washout period was allowed between treatments. Haematology, TSP, COP, plasma osmolality, glucose, BUN, serum lactate, electrolytes, venous blood pH, ultrasonographic splenic size and degree of clinical sedation were evaluated at different time points post-injection and compared to baseline values. All treatments induced similar clinical sedation in the mares. A significant change over time in PCV and TSP following each treatment was identified, with overall median (range) maximal reductions compared to baseline of 20.9% (12.9 - 27.3%) and 5.8% (3.0 - 10.3%), respectively. Additionally, changes over time were significant for RBC count, BUN, COP and Ca2+, which decreased; and glucose, plasma osmolality, Na+ and splenic size, which increased, when compared to baseline. There was no significant main effect of treatment on PCV, TSP or any other parameters measured except for glucose. This study concluded that changes in PCV, TSP and other biochemical parameters induced by α2 agonists should be taken into consideration when assessing critically ill horses that received these drugs. There was evidence of splenic RBC sequestration as well as fluid shifts; therefore, the results suggest a multifactorial cause for the changes in PCV and TSP. / Dissertation (MSc)--University of Pretoria, 2011. / Companion Animal Clinical Studies / unrestricted

Runx1 is a master regulator of hematopoiesis, required for the initiation of definitive hematopoiesis in the embryo and essential for appropriate differentiation of many hematopoietic lineages in the adult. The roles of Runx1 in normal hematopoiesis are juxtaposed with the high frequency of Runx1 mutations and translocations in leukemia. Leukemia associated Runx1 mutations that retain DNA-binding ability have truncations or frame shifts that lose C-terminal domains. These domains are important for subnuclear localization of Runx1 and protein interactions with co-factors. The majority of leukemia associated Runx1 translocations also replace the C-terminus of Runx1 with chimeric fusion proteins. The common loss of Runx1 C-terminal domains in hematopoietic diseases suggests a possible common mechanism. We developed a panel of mutations to test the functions of these domains in vitro, and then developed mouse models to examine the consequences of losing Runx1 C-terminal domains on hematopoietic development and leukemogenesis in vivo. We previously observed that overexpression of a subnuclear targeting defective mutant of Runx1 in a myeloid progenitor cell line blocks differentiation. Gene expression analysis before differentiation was initiated revealed that the mutant Runx1 was already deregulating genes important for maturation. Furthermore, promoters of the suppressed genes were enriched for binding sites of known Runx1 co-factors, indicating a non-DNA-binding role for the mutant Runx1. To investigate the in vivo function of Runx1 C-terminal domains, we generated two knock-in mouse models; a C-terminal truncation, Runx1Q307X, and a point mutant in the subnuclear targeting domain, Runx1 HTY350-352AAA . Embryos homozygous for Runx1 Q307X phenocopy a complete Runx1 null and die in utero from central nervous system hemorrhage and lack of definitive hematopoiesis. Embryos homozygous for the point mutation Runx1HTY350-352AAA bypass embryonic lethality, but have hypomorphic Runx1 function. Runx1HTY350-352AAA results in defective growth control of hematopoietic progenitors, deregulation of B-lymphoid and myeloid lineages, as well as maturation delays in megakaryocytic and erythroid development. Runx1 localizes to subnuclear domains to scaffold regulatory machinery for control of gene expression. This work supports the role of transcription factors interacting with nuclear architecture for greater biological control, and shows how even subtle alterations in that ability could have profound effects on normal biological function and gene regulation.

No description available.

Pulmonary circulation is a high flow, low resistance, and low pressure system. Several pathologies, including mitral stenosis, may elevate the impedance of this blood circuit and lead to a pulmonary arterial hypertension. Such syndrome is usually related to a high morbity and patient s death may occur because of the ischemic failure of right ventricle. The use of systemic vasodilating drugs to treat this syndrome is limited by the simultaneous systemic arterial hypotension they often produce. More selective agents to the pulmonary vasculature, such as synthetic analogs of prostacyclin, endothelin receptor inhibitors, and phosphodiesterase III inhibitors, have been choosen for medium and long-term treatment. Unfortunately, the most selective pulmonary hypotensive agent, the inhaled nitric oxide, which is used for short-term treatment, requires special and costly equipment for its administration, making it inaccessible to many hospitals. Furthermore, some degree of toxicity was associated with that substance. The lack of an ideal substance that simultaneously shows pulmonary selectivity, atoxicity, easy handling, accessibility and low cost, motivated the present study to test the effects of clonidine on pulmonary circulation. Clonidine is an alfa-2 adrenergic agonist. It promotes a systemic cardiocirculatory balance by modulating the adrenergic discharge at both central and peripheral levels. When used in clinical doses it presents no toxicity. Furthermore, it is easy to handle, accessible, and inexpensive. However, little has been reported about its pulmonary effect. Therefore, this work aimed to evaluate the effects of clonidine on the pulmonary arterial pressure, on the hemodynamics parameters concerned to the pulmonary circulatory system, as well as on the right ventricular function. At the same time, the action of clonidine on the systemic hemodynamics, cardiac rate, cardiac index and stroke index was also evaluated. This investigation took into account the degree of selectivity of this agent to the pulmonary vessels as well as the presence of a biphasic effect on the pulmonary arterial pressure. This effect has been largely reported on the vascular periferal system. The present research was performed as a prospective clinical trial developed on a group of 16 patients with pulmonary hypertension caused by mitral stenosis of rheumatic origin. Data were obtained before the anesthetic induction, but under the patient sedation. During the control phase, the variations of hemodynamic parameters under the action of a placebo were evaluated. During the test phase, the behavior of these parameters was evaluated under the clonidine effect. The time schedule for data measurements was the following: T0 (initial control); T1 (10 minutes after placebo administration); T2 (20 minutes after placebo administration); T3 (10 minutes after clonidine administration); T4 (20 minutes after clonidine administration). T2 was used as the control time to study the clonidine effects. Statistical analysis showed that during the control phase the variables remained unchanged, but under the effect of clonidine there was a significant reduction of the mean values concerned to the following parameters: pulmonary arterial mean pressure (27.1%) and systemic arterial mean pressure (20%), pulmonary vascular resistance index (34%) and systemic vascular resistance index (14.6%), right and left ventricular systolic work indexes (19.9% and 10%, respectively), right atrium pressure (11.5%), pulmonary arterial wedge pressure (21.5%), heart rate and cardiac index (15.8% and 7.9%, respectively). Besides that, a significant increase of the stroke index (10.2%) occured. The biphasic effect on the sistemic arterial pressure occured in 50% of the studied patients, whereas the same effect on the pulmonary arterial pressure was observed in 20% of the same sample. Clonidine also exerted a moderately selective action on the pulmonary circulation, demonstrated through the reduction of the relationship between mean value of the pulmonary vascular resistance index and mean value of the systemic vascular resistance index evaluated at the times T2 and T3. / A circulação pulmonar é um sistema de alto fluxo, baixa resistência e baixa pressão. Patologias diversas, dentre elas a estenose mitral, podem elevar a impedância desse circuito, desencadeando a síndrome de hipertensão arterial pulmonar. Esta cursa com elevada morbidade, podendo levar ao óbito pela falência isquêmica do ventrículo direito. A utilização de drogas vasodilatadoras periféricas no tratamento dessa síndrome ficou limitada pela simultânea hipotensão arterial sistêmica que provoca. Agentes mais seletivos sobre a vasculatura pulmonar, como os análogos sintéticos da prostaciclina, os inibidores dos receptores de endotelina e os inibidores da fosfodiesterase III, têm sido as drogas de eleição para o tratamento de médio e de longo prazo. O mais seletivo dos agentes hipotensores pulmonares, o óxido nítrico inalado, aplicado ao tratamento de curto prazo, exige equipamento especial e oneroso para a sua administração, tornando-o inacessível a muitos nosocômios. Paralelamente, possui potencial toxicidade. A inexistência de um fármaco ideal que apresente, simultaneamente, seletividade sobre a pequena circulação, atoxicidade, fácil manuseio e disponibilidade, além de ser pouco oneroso, conduziu ao estudo da clonidina sobre a árvore circulatória pulmonar. Este agente terapêutico é um agonista alfa-2 adrenérgico, com efeitos favoráveis reconhecidos sobre o equilíbrio circulatório sistêmico por modular a descarga adrenérgica em níveis central e periférico. É atóxico quando utilizado em doses clínicas. Além disso, oferece fácil manuseio, boa acessibilidade e baixo custo. Os estudos a respeito da sua ação pulmonar são escassos. Assim, a presente investigação teve como objetivo avaliar os efeitos da clonidina sobre a pressão arterial pulmonar, sobre os demais parâmetros hemodinâmicos da pequena circulação e sobre a função ventricular direita. Paralelamente, analisou as ações sobre a hemodinâmica sistêmica, a freqüência cardíaca, o índice cardíaco e o índice de ejeção. Foi também investigado o grau de seletividade pulmonar desse agente, bem como a presença de um efeito bifásico sobre a pressão arterial pulmonar, pois este efeito tem sido amplamente relatado no sistema vascular periférico. Para a execução dos objetivos propostos, um ensaio clínico prospectivo, realizado antes da indução anestésica, mas sob sedação, foi desenvolvido num grupo de 16 pacientes, todos portadores de hipertensão pulmonar resultante de estenose mitral de origem reumática. Durante a fase controle foram analisadas as variações dos parâmetros hemodinâmicos sob a ação de um placebo. Durante a fase teste foi avaliado o comportamento dos mesmos parâmetros sob a ação da clonidina. A padronização dos tempos nos quais se fez a coleta de dados foi a seguinte: T0 (controle inicial); T1 (10 min após a administração do placebo); T2 (20 min após o placebo); T3 (10 min após a administração da clonidina); T4 (20 min após a clonidina). A análise estatística dos resultados demonstrou não haver alteração das variáveis estudadas durante a fase controle. Todavia, sob o efeito da clonidina houve variações estatisticamente significantes dos mesmos parâmetros nos seus valores médios: redução da pressão arterial pulmonar média (27,1%) e da pressão arterial sistêmica média (20%), dos índices de resistência vascular pulmonar (34%) e sistêmica (14,6%), dos índices de trabalho sistólico dos ventrículos direito (19,9%) e esquerdo (10%), da pressão do átrio direito (11,5%), da pressão de oclusão da artéria pulmonar (21,5%), da freqüência cardíaca (15,8%) e do índice cardíaco (7,9%), ao lado de uma elevação significante do índice de ejeção (10,2%). O efeito bifásico sobre a pressão arterial sistêmica ficou evidente em 50% dos pacientes estudados, enquanto que o mesmo efeito sobre a pressão arterial pulmonar ocorreu em 20% da amostra estudada. A clonidina também exerceu uma ação moderadamente seletiva sobre a circulação pulmonar, demonstrada através da diminuição do quociente obtido entre o valor médio do índice de resistência vascular pulmonar e valor médio do índice de resistência vascular sistêmica, ambos avaliados nos tempos T2 e T3.

Leukemia is a hematopoietic cancer that is characterized by the abnormal differentiation and proliferation of hematopoietic cells. It is ranked 7th by death rate among cancer types in USA, even though it is not one of the top 10 cancers by incidence (USCS, 2010). This indicates an urgent need for more effective treatment strategies. In order to design the new ways of prevention and treatment of leukemia, it is important to understand the molecular mechanisms involved in development of the disease. In this study, we investigated mechanisms involved in the development of acute myeloid leukemia (AML) that is associated with CBF fusion genes. The RUNX1 and CBFB genes that encode subunits of a transcriptional regulator complex CBF, are mutated in a subset (20 – 25%) of AML cases. As a result of these mutations, fusion genes called CBFB-MYH11 and RUNX1-ETO arise. The chimeric proteins encoded by the fusion genes provide block in proliferation for myeloid progenitors, but are not sufficient for AML development. Genetic studies have indicated that activation of cytokine receptor signaling is a major oncogenic pathway that cooperates in leukemia development. The main goal of my work was to determine a role of two factors that regulate cytokine signaling activity, the microRNA cluster miR-17-92 and the thrombopoietin receptor MPL, in their potential cooperation with the CBF fusions in AML development. We determined that the miR-17-92 miRNA cluster cooperates with Cbfb-MYH11 in AML development in a mouse model of human CBFB-MYH11 AML. We found that the miR-17-92 cluster downregulates Pten and activates the PI3K/Akt pathway in the leukemic blasts. We also demonstrated that miR-17-92 provides an anti-apoptotic effect in the leukemic cells, but does not seem to affect proliferation. The anti-apoptotic effect was mainly due to activity of miR-17 and miR-20a, but not miR-19a and miR-19b. Our second study demonstrated that wild type Mpl cooperated with RUNX1-ETO fusion in development of AML in mice. Mpl induced PI3K/Akt, Ras/Raf/Erk and Jak2/Stat5 signaling pathways in the AML cells. We showed that PIK3/Akt pathway plays a role in AML development both in vitro and in vivo by increasing survival of leukemic cells. The levels of MPL transcript in the AML samples correlated with their response to thrombopoietin (THPO). Moreover, we demonstrated that MPL provides pro-proliferative effect for the leukemic cells, and that the effect can be abrogated with inhibitors of PI3K/AKT and MEK/ERK pathways. Taken together, these data confirm important roles for the PI3K/AKT and RAS/RAF/MEK pathways in the pathogenesis of AML, identifies two novel genes that can serve as secondary mutations in CBF fusions-associated AML, and in general expands our knowledge of mechanisms of leukemogenesis.

Runt related transcription factors (Runx) play an important role in mammalian development by regulating the expression of key genes involved in cell proliferation, differentiation and growth. The work described in this thesis details the mechanisms by which the activity of two members of this family are regulated in human cells. Chapter One provides a brief introduction of Runx transcription factors. Chapter Two describes the regulation of Runx2 protein by the PI3 kinase/Akt pathway in human breast cancer cells. The PI3 kinase/Akt pathway is one of the major signal transduction pathways through which growth factors influence cell proliferation and survival. It is also one of the most frequently dysregulated pathways in human cancers. We identify Runx2 protein, a key regulator of breast cancer invasion as a novel substrate of Akt kinase and map residues of Runx2 that are phosphorylated by Akt in breast cancer cells. Our results show that phosphorylation by Akt increases the binding of Runx2 protein to its target gene promoters and we identify the phosphorylation events that enhance DNA binding of Runx2. Our work establishes Runx2 protein as a critical effecter downstream of Akt that regulates breast cancer invasion. In Chapter Three we describe the subnuclear localization of the tumor suppressor protein Runx3 during interphase and mitosis. We find that similar to other Runx family members, Runx3 protein resides in nuclear matrix associated foci during interphase. We delineate a subnuclear targeting signal that directs Runx3 to these nuclear matrix associated foci. Our work establishes that this association of Runx3 protein with the nuclear matrix plays a vital role in regulating its transcriptional activity. Chromatin immunoprecipitation results show that Runx3 occupies rRNA promoters during interphase. We also find that Runx3 remains associated with chromosomes during mitosis and localizes with nucleolar organizing regions (NORs), reflecting an interaction with epigenetic potential. This thesis provides novel insights into various mechanisms by which cells regulate the activity of Runx proteins.

Yes / Background: Prescribing drugs for psychosis (antipsychotics) is challenging due to high rates of poor treatment outcomes, which are in part explained by an individual’s genetics. Pharmacogenomic (PGx) testing can help clinicians tailor the choice or dose of psychosis drugs to an individual’s genetics, particularly psychosis drugs with known variable response due to CYP2D6 gene variants (‘CYP2D6-PGx antipsychotics’). Aims: This study aims to investigate differences between demographic groups prescribed ‘CYP2D6-PGx antipsychotics’ and estimate the proportion of patients eligible for PGx testing based on current pharmacogenomics guidance. Methods: A cross-sectional study took place extracting data from 243 patients’ medical records to explore psychosis drug prescribing, including drug transitions. Demographic data such as age, sex, ethnicity, and clinical sub-team were collected and summarised. Descriptive statistics explored the proportion of ‘CYP2D6-PGx antipsychotic’ prescribing and the nature of transitions. We used logistic regression analysis to investigate associations between demographic variables and prescription of ‘CYP2D6-PGx antipsychotic’ versus ‘non-CYP2D6-PGx antipsychotic’. Results: Two-thirds (164) of patients had been prescribed a ‘CYP2D6-PGx antipsychotic’ (aripiprazole, risperidone, haloperidol or zuclopenthixol). Over a fifth (23%) of patients would have met the suggested criteria for PGx testing, following two psychosis drug trials. There were no statistically significant differences between age, sex, or ethnicity in the likelihood of being prescribed a ‘CYP2D6-PGx antipsychotic’. Conclusions: This study demonstrated high rates of prescribing ‘CYP2D6-PGx-antipsychotics’ in an EIP cohort, providing / This research was supported by the National Institute for Health and Care Research (NIHR) Yorkshire and Humber Patient Safety Translational Research Centre (NIHR Yorkshire and Humber PSTRC). This research has been funded through a scholarship from the Bradford District Care NHS Foundation Trust in partnership with the University of Bradford.