The Institute of Medicine identified that 98,000 deaths occur in hospitals each year due to poor decision-making. The need for better understanding of decision-making in patient care is evident. The purpose of this study is to explore nurses' perceptions of clinical decision-making for a patient who experienced a clinical event. The overarching framework for this research is the Effective Nurse to Nurse Communication framework which uses clinical events, or sudden changes in patient condition, to explore nurse communication between nurses who respond to a clinical event and nurses who receive report from the responding nurse about the clinical event. Naturalistic Decision Making is the framework used to explore the decision-making factors used by experienced decision makers in real world conditions. These frameworks provided the basis for data collection, interview question development, and facilitated data analysis. Twenty nurses in an urban acute care hospital were interviewed at their workplace about a patient who had experienced a sudden change in condition in the previous 24 hours. These interviews were transcribed and analyzed using content analysis. Categories that emerged were: Awareness of Patient Status, Nursing Roles (outside of specific patient care), Goals, Education / Certification / Hospital Training to support decision-making, Experience and Decision-Making, Time Pressure, Teamwork / Support from Staff, Resources, Following Established Routine. Patient Education, and Consideration of Options to Meet Goals. Further analysis indicates that elements of decision-making differ between responding and receiving nurses and based on experience level of the nurse. Strengths, limitations, and suggestions for future research are presented.

Pneumonia and sepsis are distinct but linked public health concerns. Each condition is the leading cause of the other; however, the responses controlling the susceptibility between the two disease processes remain speculative. The acute phase response (APR) is an important component of the host immune response during pneumonia and sepsis, and primarily driven by the activation of hepatocyte transcription factors NF-κB RelA and STAT3. While the NF-κB pathway is essential for inflammation and hepatocyte function, its inactivation has been associated with hepatotoxicity. Liver injury is an independent risk factor for sepsis morbidity and mortality, suggesting that pathways promoting liver homeostasis may limit the systemic consequences of pneumonia. To identify conditions in which NF-κB RelA is required for liver resilience, we challenged mice lacking hepatocyte RelA (hepRelAΔ/Δ) and wildtype (WT) controls with E. coli, K. pneumoniae, S. pneumoniae, LPS, or αGalCer to induce pneumonia, sepsis, and/or NKT cell activation. Severe hepatotoxicity was observed in hepRelAΔ/Δ mice in all conditions examined in association with apoptosis, which could be prevented by neutralization of TNFα. Lastly, these changes were associated with remodeling of the hepatic transcriptome, likely reflecting both the cause and consequence of hepatoxicity. We have previously shown that activation of STAT3 in hepatocytes limits pneumonia susceptibility during endotoxemia, but the mechanisms whereby this liver APR provides protection are unknown. Iron sequestration is a defense mechanism against bacterial infections, which require iron for growth. Based on previous observations that alveolar lining fluid is favorable for bacteria in the absence of liver STAT3, we investigated whether liver APR limits pneumonia susceptibility during sepsis by withholding iron to prevent bacterial outgrowth. WT mice or mice lacking hepatocyte STAT3 (hepSTAT3Δ/Δ) mice were challenged with endotoxemia followed by E. coli pneumonia, or cecal ligation and puncture (CLP). Induction of mRNA encoding several essential iron-regulating factors was ablated in hepSTAT3Δ/Δ mice after endotoxemia and pneumonia, and post CLP. Additionally, liver STAT3 activation significantly remodeled the pulmonary transcriptome during endotoxemia, which potentially represents other protective mechanisms. Taken together, these results suggest that hepatic APR is an important immunological interface modulating pneumonia and sepsis interaction and susceptibility.

Stress can have influence on pain sensitivity, but the direction of its effects remains unclear. Previous research has reported both increased and decreased pain sensitivities under stress with different sensory tasks. The aim of the current study was to investigate the effect of stress on pain sensitivity using multiple psychological stressors in a relatively large sample of young men and women. Sixty-two participants were included, and pain thresholds, tolerance, and temporal summation were tested using thermal, mechanical, and dynamic tasks before and after stress. A condition of stress was induced by the Stroop task and a mental arithmetic task. On average, there were no significant differences between stress and no stress conditions. Although not significant, pressure thresholds and tolerance had a tendency to decrease under stress conditions, and thermal thresholds and tolerance had a tendency to increase under stress conditions. Temporal summation did not change regardless of condition. These findings suggest that individual differences in response to stress and type of task being completed may play a role in how stress affects pain sensitivity. / 2021-06-17T00:00:00Z

Orientador: Marcos Antônio de Oliveira / Resumo: L-asparaginases (ASNases) bacterianas são importantes biofármacos utilizados no tratamento de leucemia linfoide aguda (LLA), uma vez que este tipo tumoral é dependente da disponibilidade de asparagina (Asn) extracelular. As ASNases bacterianas são capazes de hidrolisar eficientemente Asn em ácido aspártico (Asp) e amônia (NH3), diminuindo a disponibilidade de Asn para células tumorais e induzindo apoptose. Comercialmente, indústrias farmacêuticas internacionais produzem ASNases de Escherichia coli e Erwinia chrysanthemi, entretanto, ASNase de nenhuma origem é produzida pelas indústrias farmacêuticas brasileiras. Adicionalmente, o tratamento com estas enzimas produz efeitos colaterais, entre eles imunogênicos, que estão relacionados com a alta massa molecular da enzima (140kDa) e neurológicos, atribuídos a atividade secundária de glutaminase (GLNase). Neste contexto, fontes alternativas destas enzimas e também a auto-suficiência em suas produções são importantes para mitigar os efeitos colaterais e evitar falhas no tratamento devido a flutuações internacionais de sua fabricação. Neste trabalho, realizamos a caracterização de uma ASNase de levedura, denominada de ASNaseM que compartilha elevada homologia (maior que 30% de identidade e 40% de similaridade) com as enzimas bacterianas utilizadas no tratamento da LLA e que possui todos os aminoácidos envolvidos na catálise conservados, sugerindo uma fonte alternativa potencial para o tratamento da LLA. Experimentos de cromatografia... (Resumo completo, clicar acesso eletrônico abaixo) / Bacterial L-asparaginases (ASNases) are important biopharmaceuticals used in the treatment of acute lymphoid leukemia (ALL), since this tumor type is dependent on the availability of extracellular asparagine (Asn). Bacterial ASNases are able to efficiently hydrolyze Asn in aspartic acid (Asp) and ammonia (NH3), decreasing the availability of Asn to tumor cells and inducing apoptosis. Commercially, international pharmaceutical industries produce ASNases from Escherichia coli and Erwinia chrysanthemi, however none ASNase is produced by the Brazilian pharmaceutical companies. Additionally, the treatment with these enzymes can produce side effects, among them immunogenic ones, that are related to the high molecular weight of the enzyme (140kDa) and neurological, attributed to the glutaminase secondary activity (GLNase), being glutamine (Gln) the most abundant amino acid in the bloodstream. In this context, alternative sources of these enzymes as also the self-sufficiency of the production are important to mitigate side effects and avoid treatment failures due to international fluctuations in their manufacture. In this work, we performed the characterization of a yeast ASNase, called ASNaseM, which shares high homology (higher than 30% identity and 40% similarity) with the bacterial enzymes used in the treatment of ALL, and which has all the amino acids involved in the catalysis conserved, suggesting a potential alternative source for the treatment of ALL. Molecular exclusion chro / Doutor

Background: Acute kidney injury (AKI) is a highly prevalent clinical disorder with significant mortality and no current treatment. The Burns Lab has previously shown that endothelial colony forming cells (ECFCs) release exosomes highly enriched in pro-survival micro-RNA-486-5p. In our mouse model of AKI, intravenous (i.v.) injection of ECFCs or their exosomes protects against kidney ischemic injury, associated with reduction in PTEN, a target of miR-486-5p. Mechanisms mediating recruitment and retention of exosomes are unclear. The interaction of CXC chemokine receptor type 4 (CXCR4) with stromal cell-derived factor (SDF)-1α promotes ECFC adhesion and migration in hypoxic endothelial cells. Whether exosomal miR-486-5p is critical to the prevention of ischemic injury is unclear. The current study aimed to investigate biodistribution and targeting mechanisms of ECFC-derived exosomes, to investigate the delivery and therapeutic potential of miR-486-5p alone, and to determine whether sex differences alter the treatment efficacy. Methods: ECFC-derived exosomes were isolated from cultured media by differential centrifugation and characterized using nanoparticle tracking analysis and immunoblot. Kidney ischemic injury was induced in male and female FVB mice by bilateral renal vascular clamping (30 min). Exosomes (20 µg) or Invivofectamine-mimic complex containing miR-486-5p (1mg/kg) were injected at the start of kidney reperfusion via tail vein. Organs were removed and assays were performed to identify structure and function. In vitro cell studies were also used when necessary. Results: ECFC-derived exosomes preferentially target the ischemic kidney, its endothelium and tubular epithelium, which correlates with increases in miR-486-5p. The transfer of exosomes may be mediated by macropinocytosis by target cells. The SDF-1α/CXCR4 axis plays a role in targeting exosomes to the site of injury. miR-486-5p alone has a similar therapeutic efficacy in preventing ischemia/reperfusion injury as ECFC-exosomes in the mouse model of AKI. Both male and female mice respond to both therapies, however female mice are protected against ischemia reperfusion injury. Conclusions: These results suggest that the protective effects of ECFCs or their exosomes in ischemic AKI may be largely mediated by pro-survival miR-486-5p. These data provide further support for the promising therapeutic potential of ECFC-derived exosomes and miR-486-5p in human AKI.

Introdução: As doenças cardiovasculares constituem a principal causa de morbimortalidade nacional e apresentam-se principalmente na forma de doença arterial coronariana, cujas principais manifestações se caracterizam pelas síndromes coronarianas agudas: angina instável e infarto agudo do miocárdio. Nesse sentido, realizou-se um estudo com o objetivo de caracterizar o perfil bio-psico-social dos pacientes após síndromes coronarianas agudas, identificando os fatores que possam interferir na adesão ao tratamento no que diz respeito ao não comparecimento às consultas, interrupção do tratamento e controle de pressão arterial, além de associar o perfil bio-psico-social dos pacientes com fatores relacionados à adesão. Casuística e Método: Estudo descritivo e exploratório, realizado em um hospital universitário da cidade de São Paulo, analisou 85 pacientes com diagnóstico de síndromes coronarianas agudas. Após receberem alta, os pacientes foram entrevistados em ambulatórios para obtenção de dados estruturais, socioeconômicos, hábitos de vida, conhecimento da doença e do tratamento. Com o intuito de avaliar o bem estar psicológico dos pacientes, o questionário de saúde geral de Goldberg foi aplicado. Os dados foram processados no sistema SPSS v.7.5. O nível de significância adotado foi 0,05. Resultados: Foram estudados 85 pacientes, 56% homens, 69% com companheiro, 59±9,6 anos, 85% pertencentes à etnia branca, 52% com ensino fundamental, 54% com renda entre 2 e 5 salários, 79% com antecedentes de hipertensão arterial, 62% com dislipidemia e 40% para infarto agudo do miocárdio. Cerca de 35% relataram o não comparecimento às consultas e a interrupção do tratamento. Em relação à atitude frente à necessidade de tomar medicamentos, 63% dos pacientes relatou esquecimento esporádico ou constante dos remédios. A análise de regressão logística indicou a associação independente para as seguintes variáveis (OD Odds ratio, IC intervalo de confiança a 95%): 1- não comparecimento às consultas, etnia branca (OR=0,27 IC 95% 0,08-0,86) e hábitos alimentares inadequados (OR=1,07 IC 1,00-1,45); 2- interrupção do tratamento associado com faltas às consultas (OR=6,09 IC 1,81-20,49), consumo de bebida alcoólica (OR=5,05 IC 1,61-15,76) e automedicação (OR=7,89 IC 2,39-26,05); 3- pressão arterial não controlada (=140/90 mmHg) com acompanhamento no ambulatório de coronária (OR=2,78, IC 1,01-7,65). A maior freqüência de alteração no quarto percentil nos domínios do questionário de saúde geral de Goldberg foram associados às seguintes variáveis: 1- estresse associado à automedicação (OR=6,09 IC 1,32-14,5) e HDLc =40mg/dL (OR=1,04 IC 1,00-1,08); 2- auto-eficácia com acompanhamento no ambulatório de coronária (OR=2,78 IC 1,19-12,23), automedicação (OR=4,62 IC 1,46-14,95) e HDLc =40mg/dL (OR=1,04 IC 1,19-12,23); 3- distúrbios do sono associados com referência de ansiedade (OR=5,61 IC 1,65-19,09), e colesterol total = 200 mg/Dl (OR=4,42 IC 1,36- 14,38); 4- distúrbios psicossomáticos associados ao sexo feminino (OR=6,57 IC 1,96-22,0) e relato de ansiedade (OR=4,06 IC 1,24-13,3); 5- severidade da ausência de saúde mental associado ao sexo feminino (OR=3,96 IC 1,26- 12,43) e automedicação (OR=3,39 IC 95% 1,07-10,70). Conclusão: Características estruturais e psicológicas, hábitos de vida inadequados e atitudes frente ao tratamento medicamentoso influenciaram aspectos da adesão ao tratamento, tais como o não comparecimento às consultas e a interrupção do tratamento. Em face dos dados obtidos, os profissionais de saúde devem implementar estratégias para atender os pacientes com síndrome coronariana aguda, visando à prevenção secundária. / Introduction: The cardiovascular diseases are the most important cause of mortality in the country and show mainly in the form of coronary arterial disease, which the main manifestations are characterized by the acute coronary syndrome: instable angina, acute attack of the myocardium. In this way, a study was made with the aim to characterized the bio-psychosocial profile of the patients after the acute coronary syndrome, recognizing the factors which could interfere in the adherence to the treatment about the non attendance to the appointments, interruption of the treatment and the control of the blood pressure, besides the association of the bio-psychosocial profile of the patients to the factors connected to the adherence. Method and Casuistic: A descriptive and exploring study, made in a University hospital in the city of São Paulo that analyzed 85 patients with the diagnostics of the acute coronary syndrome. After receiving the doctor’s avail to leave the hospital, the patients were interviewed in ambulatories in order to collect structure, socioeconomic, habits of life, knowledge of the disease and of the treatment data. The main purpose was to evaluate the psychological welfare state of the patients; the questionnaire of general health was used. The results were run in the system SPSS v. 7.5. and the significance level adopted was 0,05. Results: 85 patients were studied, 56% men, 69% ith companion, 59+-9,6 years old, 85% white, 52% finished the elementary school, 54% with the income of between 2 and 5 salaries, 79% with the precedents of high blood pressure, 62% with high blood cholesterol and 40% for the acute myocardium attack. About 35% of them spoke about the non attendance to the appointments and the interruption of the treatment. About the attitude towards the necessity to take medicines, 63% of the patients spoke about the constant or periodical carelessness of the medicines. The analysis of logistic regression indicated the independent association to the following varieties: (OD odds ratio, IC confidence break around 95%): 1 – non attendance to the appointments, white ethnic (OR = 0,27 IC 95% 0,08- 0,86) and bad eating habits (OR=1,07 IC 1,00-1,45); 2 – interruption of the treatment associated to the non attendance to the appointments (OR=6,09 IC 1,81-20,49), the alcoholic drinks consumption (OR=5,05 IC 1,61-15,76), and auto medication (OR=7,89 IC 2,39-26,05); 3 – high blood pressure out of control (=140/90 mmHg) with the accompaniment in the coronary ambulatory (OR=2,78, IC 1,01-7,65). The higher frequency of the alterations in the percentage board in the Goldberg’s general health questionnaire dominions was associated to the following variations: 1 – Stress associated to auto medication (OR=6,09 IC 1,32-14,5) and HDLc =40mg/dL (OR=1,04 IC 1,00-1,08); 2 – auto efficiency with accompaniment in the coronary ambulatory (OR=2,78 IC 1,19-12,23), auto medication (OR=4,62 IC 1,46-14,95) and HDLc =40mg/dL (OR=1,04 IC 1,19-12,23); 3 – Sleeping disturbance associated to anxiety reference (OR=5,61 IC 1,65- 19,09) and total cholesterol total = 200 mg/Dl (OR=4,42 IC 1,36-14,38); 4 – psychosomatic disturbances associated to the female genre (OR=6,57 IC 1,96-22,0) and the report of anxiety (OR=4,06 IC 1,24-13,3); 5 – health general rate of evaluation associated to the female genre (OR=3,96 IC 1,26-12,43) and auto medication (OR=4,06 IC 1,24-13,3); Conclusion: The structural and psychological characteristics, inadequate life habits and attitudes facing the medicine treatment influence the aspects of adherence to the treatment, such as the non attendance to the appointments and the interruption of the treatment. Facing all the searched data, the health professionals must implement strategies to support the patients with acute coronary syndrome, looking for the secondary prevention.

Magister Curationis - MCur / The provision of mental health care, treatment and rehabilitation of the acutely ill mental health care users (MHCUS) poses a major challenge to the nurses working in acute units. Nurses spend long hours ensuring that acutely ill psychiatric patients receive quality patient care in acute admission units in different psychiatric hospitals in South Africa. With few studies showing a rise in the prevalence of mental disorders in the South Africa and the Western Cape Province, acute psychiatric inpatient units across the province have experienced intense pressure and persistent rise in the number of acute patient admissions. Dealing with this group of patients is a difficult task particularly for nurses who spent prolonged hours caring for them. Despite the continuing provision of care to MHCUS by nurses in acute admission units, very little is known about the lived experiences of nurses in acute admission units. The aim of this study was to explore and describe the lived experiences of nurses who care for the acutely ill MHCUS in an acute male admission unit at a psychiatric hospital in the Western Cape. Acutely ill MHCUS in acute psychiatric units show severely disturbed behaviour at times, aggression, hostility, acute psychotic symptoms and many other symptoms related to psychiatric illness. Methods: a qualitative, descriptive phenomenological research design was used to explore and describe the lived experiences of nurses who care for acutely ill patients in an acute admission unit. A purposive sample of eight nurses was selected. Individual, semi structured phenomenological interviews were used to collect data from nurses caring for MHCUS in an acute admission unit. Data saturation was reached after carrying out the eight interviews. These interviews were audio taped and transcribed verbatim and Collaizi’s (1978) seven steps method of qualitative data was applied to analyse the collected data. Findings: The study found that nurses in the acute admission unit experienced several challenges while caring for MHCUs. Nurses reported both negative and positive experiences. Positive experiences included MHCUs recovery, teamwork and passion for caring while negative experiences were feeling unappreciated and unsupported by authorities. Furthermore, they reported physical assault by MHCUs which led to fear. Challenges experienced included shortage of staff and increased workload which led to burnout amongst nurses in acute admission units.

PURPOSE: Doppler renal resistive index (RRI) has emerged in the last decade as a useful prognostic indicator for transient (fluid responsive) and persistent acute kidney injury (AKI). The determinants of RRI are largely systemic and recent studies confirm that RRI measurement could also be a useful early marker for sub-clinical AKI and post procedural AKI risk. This study aimed to determine the feasibility of RRI measurement in an Emergency Department (ED) resuscitation room setting using a point­of­care ultrasound system. METHODS: In this prospective single centre study, RRI measurement was attempted in 20 non-consecutive patients (meeting the inclusion criteria) by a single expert sonographer. RRI measurements were evaluated against context specific feasibility criteria and target outcomes. RESULTS: 20 patients (11 male, 9 female) were recruited to the study. Age of patients ranged from 33 years to 91 years (mean 62.3 years). Adequate visualisation of both kidneys was achieved in 60% of patients (n=12). In patients where it was not possible to achieve adequate views of both kidneys (n=8), limiting technical factors were shortness of breath (SOB) (n=6), high BMI (n=2). At least one measurement of RRI was achieved in 70% of patients (n=14). However, in 9 of these patients (64.3%) the Doppler spectral traces achieved were substandard and did not meet the measurement criteria for RRI as specified in the study protocol. In 30% of patients (n=6) no usable spectral trace was achieved and it was not possible to measure RRI. SOB was noted as a technical difficulty in 60% of patients (n=12) including three for whom RRI measurements were achieved. In 9 patients (45%) SOB was recorded as the primary reason for failure to acquire a usable Doppler trace. All criteria for RRI measurements were met in only 3 patients (15%). CONCLUSION: Measurement of RRI was not feasible in patients requiring resuscitation room care using a current point of care ultrasound system. If RRI is to play a useful role in this high priority patient group, adaptation of the available technology is required to mitigate the problem of image blur due to patient breathing movement.

O gene humano lysine methyltransferase 2E (KMT2E) pertence ao grupo Trithorax (TrxG) e age como proteína modificadora de histonas envolvida no controle transcricional de genes relacionados a hematopoiese. Foi previamente identificado como supressor tumoral, atuando sobre a diferenciação, proliferação e ciclo celular. DAMM et al. (2011) e LUCENA-ARAÚJO et al. (2014) descreveram a associação entre baixos níveis de expressão do gene KMT2E e desfechos desfavoráveis do tratamento de pacientes com leucemia mielóide aguda (LMA) e leucemia promielocítica aguda (LPA), respectivamente. O objetivo desse trabalho foi estudar os efeitos do aumento da expressão do gene KMT2E na leucemia mielóide aguda (LMA). Foi utilizada a linhagem celular U937, reconhecida como modelo de LMA, e o aumento da expressão do gene de interesse foi obtido por meio da transfecção das células com um vetor lentiviral contendo o cDNA codificante para a isoforma longa do gene (pCDH-MSCV-MCS-EF1-GFP+Puro, aqui chamado pMEG). As partículas lentivirais foram geradas por co-transfecção em células da linhagem HEK 293T, e posteriormente, titulados com a linhagem celular HT 1080. A expressão do gene e a presença da proteína foram confirmadas por qPCR e western blotting, respectivamente. Foram realizados ensaios funcionais de ciclo celular, proliferação, viabilidade, apoptose espontânea e induzida por trióxido de arsênico e luz ultravioleta e diferenciação celular induzida por 12-miristato 13-acetato de forbol (TPA), com as amostras U937 wild type (WT), U937 pMEG (U937 transduzidas com o vetor vazio) e U937 pMEG-KMT2E. Também foram realizadas mensurações da massa tumoral das células inoculadas em camundongos NSG. A expressão relativa do gene KMT2E na célula U937 pMEG-KMT2E foi 1000 vezes mais alta que na célula U937 sem a modificação genética. Os ensaios de diferenciação celular demonstraram que as células U937 pMEG-KMT2E apresentaram maior diferenciação em monócitos/macrófagos que as células controles, quando levada em consideração a marcação para o antígeno CD11c. A expressão induzida de KMT2E em células U937 não alterou a proliferação, viabilidade, ciclo celular, apoptose, ix espontânea ou induzida e o aspecto clonogênico in vitro, porém, foi associado a um maior crescimento tumoral em modelo animal. Nossa hipótese para justificar as diferenças entre os achados in vitro e in vivo é que o aumento da expressão de KMT2E, talvez por meio do aumento de CD11c, facilitou a interação entre as células e o microambiente, estimulando assim o crescimento tumoral in vivo. / The human lysine methyltransferase 2E (KMT2E) gene belongs to the Trithorax (TrxG) group and acts as a histone modifying protein participating in the transcriptional regulation of hematopoiesis-related genes. KMT2E has been previously described as a tumor suppressor, involved in cellular differentiation, proliferation and cell cycle progression. DAMM et al. (2011) and LUCENA-ARAÚJO et al. (2014) described the association between low levels of KMT2E gene expression and poor treatment outcomes in patients with acute myeloid leukemia (AML) and acute promyelocytic leukemia (APL), respectively. The aim of this project was to study the effects of high levels of KMT2E expression in acute myeloid leukemia (AML). For this purpose, the U937 AML cell line was used and an high expression of the gene was obtained by transfecting the cells with a lentiviral vector containing the cDNA encoding the long isoform of the gene (pCDH-MSCV-MCS-EF1- GFP + Pure, here called pMEG). The lentiviral particles were transfected into HEK 293T cells and the viral concentration was determined by titration using HT 1080 cells. The gene expression and the protein presence were confirmed by qPCR and western blotting, respectively. All experiments to determine the biological function of overexpressed KMT2E were conducted with U937 wild type, U937 pMEG (U937 transduced with the empty vector) and U937 pMEG-KMT2E cells. In-vitro the impact of overexpressed KMT2E was studied on cell cycle progression, proliferation and cell viability, spontaneous and induced apoptosis by arsenic trioxide and ultraviolet light and cell differentiation induced by 12-myristate 13-phorbol acetate (TPA). In vivo, the effect of overexpressed KMT2E was detected by comparing the tumor mass growth in NSG mice when inoculating U937 pMEG and pMEG-KMT2E cells in each flank of the same mouse. The relative expression level of the KMT2E gene in pMEG-KMT2E U937 cells was 1000 higher than in the wild type U937 strain. The cell differentiation assay revealed that U937 pMEG-KMT2E cells presented an increased monocyte/macrophage differentiation, when analyzing the CD11c antigen. Induced xi overexpression of KMT2E in U937 cells did not alter cell proliferation, cell viability, cell cycle progression, spontaneous or induced apoptosis or clonogenic appearance in vitro. However, the overexpression of KMT2E resulted in an increased tumor mass formation in vivo. Taking our discrepant in vitro and in vivo results into account, we could hypothesize that the increased expression of KMT2E, possibly caused by the enhanced expression of CD11c, favored the interaction between U937 pMEGKMT2E cells and their microenvironment, thereby stimulating tumor growth in vivo.

In Western Europe and North America, acute myeloid leukaemia (AML) is predominantly a disease of the elderly, with a median age at the time of presentation in excess of 60 years. However, many clinical trials in AML fail to recruit elderly adults due to a combination of strict entry criteria, or physician or patient bias. Thus, clinical outcome data from many trials may not be readily applicable to older patients with the disease. Furthermore, because the clinical outcome for many older patients with AML is frequently poor, elderly patients who receive intensive chemotherapy with curative intent are frequently selected for treatment on clinical criteria rather than on objective prognostic criteria that may define clinical outcome. The karyotype at the time of presentation may be considered one of the most important prognostic factors in adult AML. Therefore, the aim of this thesis were firstly to analyse the clinical outcome data from a cohort of elderly patients managed at a single centre in order to document the cytogenetic features of AML in an elderly population, to define the prognostic importance of presentation karyotype in the elderly, and to identify other prognostic factors. Retrospective analysis clearly demonstrated improved clinical outcome for older patients with AML over time, primarily as a consequence of improved supportive care and the delivery of more intensive chemotherapy. In addition, 'unfavourable' presentation karyotype, increasing age and raised serum LDH were found to correlate with poor clinical outcome Molecular cytogenetic techniques based upon fluorescence in-situ hybridisation technology offer the chance to detect and analyse cytogenetic aberrations at a higher resolution than can be achieved with conventional techniques. The cytogenetic data provided by comparative genomic hybridisation and mulitplex fluorescence in-situ hybridisation when used in the analysis of elderly patients with AML were found to correlate well with results obtained by conventional methods. Importantly, additive cytogenetic data were more likely to be provided if multiplex-fluorescence in-situ hybridisation was used in the analysis of cases with marker chromosomes or in cases with complex karyotype, although the technique was limited by an inability to reliably detect telomeric translocations. In addition, although both techniques can be used to complement conventional G-banding analysis, conventional FISH methods are often required to confirm the results.