Dissertations / Theses on the topic 'Acute'

Prostatitis is swelling and inflammation of the prostate gland, a walnut-sized gland located directly below the bladder in men. Prostatitis can be caused by a number of different things. If it's caused by a bacterial infection, it can usually be treated successfully. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/32506

The aim was to identify diagnostic difficulties for acute abdominal pain at the emergency department and during hospital stay. A total of 3349 patients admitted to Mora Hospital with acute abdominal pain of up to seven days duration, were registered prospectively for history and clinical signs according to a structured schedule. The preliminary diagnosis from the attending physician at the emergency department, any investigations or surgery and final diagnosis were registered at a follow-up after at least one year.

There were no differences in diagnostic performance between physicians with 0.5 to 5 years of medical experience. The information collected and a careful examination of the patient was more important than formal competence. The main differential diagnostic problem was non-specific abdominal pain; this was the same for diagnoses requiring surgery. Patients originally diagnosed as not needing surgery had a median delay before operation of 22 hours (mean 40 hours, with 95% confidence interval of 30-50 hours), compared to 8 hours (mean 15 hours, 95% confidence interval of 12-28 hours) for patients with the same final follow-up diagnosis as the preliminary diagnosis. Constipation was a diagnostic pitfall, as 9% of the patients considered constipated required surgery for potentially life threatening reasons and 8% were later found to have an abdominal malignancy. Both the preliminary diagnosis and the discharge diagnosis were less reliable for elderly patients than for younger patients. Elderly patients often had specific organ disease and arrived at the emergency department after a longer history of abdominal pain.

This study confirms that assessment of suspected appendicitis can still be based on clinical judgements combined with laboratory tests. Classical clinical findings indicating localised inflammation, such as isolated pain in the right iliac fossa, rebound tenderness, right-sided rectal tenderness, pain migration to the right iliac fossa, local guarding and aggravation of pain when moving, were reliable for predicting acute appendicitis. A CT scan can be saved for the more equivocal cases of acute abdominal pain. A generous strategy regarding CT scan among elderly patients with acute abdominal pain, even in the absence of pronounced signs of an inflammatory intra-abdominal process, is recommended.

Preclinical research demonstrates that cannabinoids have differing effects in adolescent and adult animals, and human epidemiological research suggests that adolescent cannabis use has greater potential for harm than adult use. In chapters 1 and 2, I review this literature, describing the acute and non-acute effects of cannabis on memory, response inhibition and psychotic-like symptoms, with a focus on findings relating to adolescent populations and age of cannabis use onset. In chapter 3, I describe associations between adolescent cannabis use, IQ and educational performance, demonstrating that adjustment for potential confounders – most notably cigarette use – leaves cannabis use not associated with lower performance. In chapter 4, I describe the first study to compare the acute effects of cannabis in human adolescent (n=20; 16-17 years old) and adult (n=20; 24-28 years old) male cannabis users, in a placebo-controlled, double-blind cross-over design. After inhaling vaporised active or placebo cannabis, participants completed tasks assessing memory, inhibition, alongside physiological measures and subjective drug effects (e.g. “stoned”). Results showed contrasting profiles of adolescent resilience (blunted subjective, physiological and memory effects) and vulnerability (lack of satiety, impaired inhibitory processes). In chapter 5, in the same sample, I describe the acute psychotic-like effects of cannabis. Cannabis increased psychotic-like symptoms and the incidence of speech illusions in both adolescents and adults, though some self-rated effects were heightened in adults. In chapter 6, in a reduced sample, I describe the acute effects of cannabis on anhedonia (as indexed by reward responsivity, hedonic capacity and self-rated anhedonia) in adolescents (n=13) and adults (n=13). Cannabis did not affect reward responsivity or hedonic capacity in either group, though adults but not adolescents reported self-rated increases in anhedonia. In chapter 7, I integrate my findings, discuss their implications, consider limitations and suggest directions for future research into the effects of cannabis use in adolescence.

BACKGROUND: Acute transverse myelitis (ATM) may be the prelude of a wide range of diseases such as Multiple Sclerosis (MS), autoimmune, infectious, post-vacunal, post-radiotherapy and tumor related disorders. Nonetheless, the underlying etiology remains elusive in up to 16% of ATM patients. In 2002, the Transverse Myelitis Consortium Working Group (TMCWG) proposed some criteria in order to unify the concept of idiopathic ATM (IATM). ATM may present as a longitudinal extensive transverse myelitis (LETM) on the spinal Magnetic Resonance Imaging. LETM is a cardinal symptom of Neuromyelitis optica (NMO), an autoimmune chronic disease characterized by recurrent optic neuritis (ON) or LETM. In 2004, a pathogenic antibody, known as aquaporin-4 antibody (AQP4–ab) was directly related to NMO or limited forms of the disease such as LETM. Nonetheless, up to 50% of LETM patients are AQP4-ab seronegative. Recently, antibodies against the myelin- oligodendrocyte glycoprotein (MOG-ab) have been described in AQP4-ab seronegative NMO patients or limited forms of the disease. AIMS: The current work is divided in three studies. In the first study, we aimed to describe the MS conversion ratio and to identify baseline factors related to MS conversion, as well as to analyze baseline prognostic factors of disability in IATM patients fulfilling the 2002 TMCWG. In the second study, we sought to describe the etiological LETM spectrum and to analyze baseline prognostic factors related to outcome in this subgroup of patients. Finally, in the third study, we set out to describe the frequency of MOG-ab in AQP4-ab seronegative LETM and searched for differences between MOG-ab positive and negative AQP4-ab seronegative LETM patients. METHODOLOGY: The first and second studies were performed in a single center and we reviewed the epidemiological, clinical, laboratory and radiological data of 85 IATM patients fulfilling the TMCWG and 72 LETM patients. The third study is a multicenter European study with data collected in a prospective manner. AQP4-ab or MOG- ab were detected by immunohistochemistry in the two first studies and by cell based assays in the third study. All data were retrospectively analyzed. RESULTS: At the end of the first study, 13% of IATM converted to MS and an early onset of symptoms was related to MS conversion. However, laboratory findings such a negative result in the combination of oligoclonal bands (OCB) and IgG index in the cerebrospinal fluid (CSF) ruled out MS conversion. We observed that LETM and urinary sphincter dysfunction were independent baseline prognostic factors related to disability and that up to 37% of IATM patients had a final modified Rankin Score more (mRS) ≥ 2. In LETM patients, the idiopathic group and MS were the most frequent disorders involved (30.5% and 25%, respectively). NMO or limited forms were observed in less than 5%. The mRS was ≥2 at the end of follow-up in 72.2%. The presence of higher disability at onset of symptoms and elderly were independent baseline prognostic factors of disability. Up to 23% of patients presenting with AQP4-ab seronegative LETM tested positive for MOG-ab in serum. MOG-ab positive patients were younger, had CSF pleocytosis more frequently and had better outcome. Moreover, MOG-ab positive patients also showed an increase risk of ON relapse and NMO conversion. CONCLUSIONS: We identified that a subgroup of IATM patients may convert to MS, even when fulfilling the 2002 TMCWG criteria. Functional recovery in IATM is poorer in patients with urinary sphincter dysfunction at admission or LETM on MRI. We established the LETM etiological spectrum. In this subgroup of patients, while idiopathic and MS group were the most frequently involved, others such as NMO were marginally observed. Older age and clinically severe disease at onset were independent prognostic factors of poorer functional recovery in LETM patients. Finally we found that MOG-ab are present in a proportion of AQP4-ab seronegative LETM patients defining a subgroup of patients with clinical distinctive features, higher risk of ON relapses, and better outcome.
Las mielitis transversas agudas (MTA) pueden ser el comienzo de una amplia diversidad de enfermedades, siendo la más frecuente la Esclerosis Múltiple (EM). Hasta en el 16% de los pacientes que presentan una MTA, la etiología será desconocida. Un consorcio internacional (TMCWG) propuso en el año 2002 unos criterios con el fin de unificar el concepto de MTA idiopática (MTAI). Las MTA pueden presentarse como una afectación extensa de la médula espinal (LETM), siendo ésta una característica de la Neuromielitis óptica (NMO). Los anticuerpos aquaporina 4 (AQP4-ac) se objetivan en la mayoría de estos pacientes y formas limitadas de esta enfermedad, como la LETM. Sin embargo, una proporción de estos pacientes no presentan AQP4-ac y otros anticuerpos como los anticuerpos contra myelin oligodendrocyte glycoprotein (MOG-ac) han sido recientemente asociados. El presente trabajo se divide en tres estudios (dos unicéntricos y un tercero multicéntrico europeo) que tienen como objetivo describir las características de los pacientes con una MTAI, pacientes con LETM así como identificar las características de aquellos pacientes con una LETM que presenten MOG-ac. Se identificó un subgrupo no despreciable de pacientes que convertirán a EM aunque cumplan los criterios de la TMCGW para MTAI. Además se objetivó que el pronóstico es peor en pacientes con una MTAI que presentan disfunción urinaria y LETM al comienzo de los síntomas. Por otra parte, describimos el espectro etiológico de pacientes con LETM, objetivando que en la mayor parte de ellos, la causa es idiopática. Los pacientes con una LETM tendrán peor pronóstico a más edad y a mayor discapacidad al inicio de los síntomas. Finalmente, encontramos que hasta un 23% de los pacientes que presentan LETM y son seronegativos para AQP4-ac, tienen MOG-ac en el suero. Estos pacientes presentan características clínicas distintivas, mayor riesgo de neuritis óptica, de recidivas y mejor pronóstico que los pacientes sin el anticuerpo.

Introduction: Acute decompensation was defined as the acute development of one or more major complications of liver disease and it was the main cause of hospitalization in patients with cirrhosis. The acute-on-chronic liver failure (ACLF) was characterized by acute decompensation of cirrhosis, organ failure and high 28-day mortality. ACLF displayed key features of systemic inflammation and its poor outcome was closely associated with exacerbated systemic inflammatory responses. Inflammasomes were multiprotein complexes which proteolytically activates the cytokines IL-1β and IL-18. These substrates might have an effect on the development of liver disease. Extracellular vesicles (EVs) were involved in many important biological processes as well as in disease pathogenesis. The dynamics of EVs secretion by different cell types and how the secreted EVs interact to advance the pathogenesis of liver disease were still unknown. Aims: The aim of this study was to characterize the molecular pathways involved in acute decompensation of cirrhosis and ACLF through: the characterization of the inflammatory profile of patients, the in vitro evaluation of cytotoxic effects of plasma from patients on renal tubular cells, the expression of Inflammasome in these treated cells and in Peripheral Blood Mononuclear Cells (PBMC) of patients, the characterization of EVs from patients and the study of in vitro effects of isolated EVs in renal tubular cells. Material and Methods: We enrolled patients with compensated cirrhosis, acute decompensation in cirrhosis, ACLF and healthy subjects as control population. Plasma levels of IL-6, IL-1β and IL-18 were detected by ELISA assay. Cytotoxic effects of plasma on renal tubular cells were assayed by annexin V and propidium iodide kit. Inflammasomes expression was detected both in renal tubular cells treated and in PBMC extracted from patients by Real Time PCR. Plasma EVs were extracted by ultracentrifugation and concentration was measured by Nanosight. Characterization of EVs was performed by FACS analysis. Cytotoxic effects of plasma EVs on renal tubular cells were assayed by XTT assay. Results: Plasma levels of pro-inflammatory cytokines measure in the firsts patients enrolled did not differed between the groups of compensated cirrhosis, acute decompensation and ACLF. Also viability and death rate did not change in a way statistically significant in cell stimulated with plasma from the three groups of patients. Furthermore, Inflammasome gene expression in these cells did not underlines the activation of this protein complex. In PBMC from patients, gene expression of Tool-like receptor 2 (TLR-2) was significantly higher in patients with compensated cirrhosis compare to acute decompensation of cirrhosis (p=0.036). Albumin added to cell medium reduced cytotoxic effects of plasma on renal tubular cells. Plasma EVs of patients enrolled were more concentrated in ACLF groups compare to healthy subjects. EVs did not expressed selected platelets (CD41, CD42b) and monocyte markers (CD14) in their surface but they expressed marker of platelets activated endothelium (CD62E). The levels of CD62E were significantly higher in patients with ACLF compare to healthy subjects and patients with compensated cirrhosis (p=0.0041 and p=0.0111, respectively). CD40L levels were significantly higher in all patients' groups compare to healthy subjects (p<0.02). Plasma EVs from patients with acute and acute-on-chronic liver failure exerted a higher cytotoxic effects compare to healthy subjects and patients with compensated cirrhosis on renal tubular cells (p<0.0001). Cells incubated with EVs from acute and acute-on-chronic liver failure underwent to apoptosis (p<0.0001), to ROS production (p<0.0001), to lose albumin intake capabilities (p<0.0001) and reduction of Zonula Occludens-1 (ZO-1) expression (p=0.0166) compare to healthy subjects and patients with compensated cirrhosis. Instead, megalin and PGC1α expression did not change. Conclusions: The role of EVs in decompensated cirrhosis and ACLF need to be invastigated and study their hypothetic role as vehicle of mediator of extrahepatic organ injury and complications of cirrhosis.
Introduzione: Lo scompenso acuto in cirrosi è definito come la progressione acuta di una o più gravi complicanze della patologia epatica ed è la principale causa di ospedalizzazione nei pazienti con cirrosi. L'insufficienza epatica acuta su cronica (ACLF) è caratterizzata da uno scompenso acuto della cirrosi, da danno d'organo e da un elevato tasso di mortalità a 28 giorni. L'ACLF è caratterizzato da infiammazione sistemica e l'outcome infausto è strettamente associato con l'eccessiva risposta infiammatoria che si attiva nel paziente. L'inflammasoma è un complesso multi-proteico che attiva, mediante taglio proteolitico, citochine pro-infiammatorie come IL-1β e IL-18. Queste, hanno un ruolo nello sviluppo della patologia epatica. Le vescicole extracellulari (EVs) sono coinvolte in molti processi biologici importanti, sia fisiologici che patologici. Il processo di secrezione delle EVs da diversi tipi di cellule e la loro azione nel modulare l'avanzamento della patogenesi nella malattia epatica, non sono ancora completamente chiariti. Scopo: Lo scopo di questo studio è caratterizzare la via del segnale coinvolta nello scompenso acuto della cirrosi e dell'insufficienza epatica acuta-su-cronica attraverso: la caratterizzazione del profilo infiammatorio dei pazienti arruolati, lo studio in vitro dell'effetto citotossico nel plasma dei pazienti nelle cellule tubulari renali (RTC), lo studio dell'espressione dell'inflammasoma nelle cellule trattate e nelle cellule mononucleate del sangue periferico (PBMC) estratte dai pazienti, la caratterizzazione delle EVs estratte dal plasma dei pazienti arruolati e lo studio del loro effetto in vitro su colture di RTC. Materiali e Metodi: sono stati arruolati pazienti con cirrosi compensata, scompenso acuto in cirrosi, insufficienza epatica acuta-su-cronica e una popolazione di volontari sani come controllo. I livelli plasmatici di IL-6, IL-1β e IL-18 sono stati misurati con kit ELISA. L'effetto citotossico del plasma nelle RTC è stato testato con il kit costituito da annexina V e propidio ioduro. Il livello di espressione delle molecole dell'inflammasoma è stato determinato sia nelle cellule stimolate con il plasma, sia nei PBMC estratti dai pazienti, attraverso Real Time Poly Chain Reaction (RT-PCR). Le EVs plasmatiche sono state estratte mediante ultracentrifugazione e la loro concentrazione determinata con il Nanosight. La loro caratterizzazione è stata eseguita mediante analisi al FACS. L'effetto citotossico delle EVs sulle RTC è stato determinato mediante saggio XTT. Risultati: I livelli plasmatici delle citochine pro-infiammatorie, misurati nei primi pazienti arruolati, non mostra differenze tra i gruppi di pazienti con cirrosi compensata, scompensata e insufficienza epatica acuta-su-cronica. Anche la vitalità e la morte cellulare nelle colture stimolate con i plasma dei pazienti arruolati non hanno mostrato un profilo peculiare dei gruppi testati e non è stata riscontrata attivazione della trascrizione delle molecole dell'inflammasoma. L'espressione del Tool-like receptor 2 (TLR-2) nei PBMC si è dimostrata significativamente elevata nei pazienti con cirrosi compensata rispetto a quelli con scompenso acuto (p=0,036). Aggiungendo albumina al mezzo di coltura cellulare si è notata una riduzione dell'effetto citotossico del plasma dei pazienti nelle RTC. La concentrazione plasmatica di EVs risulta maggiore nei pazienti con insufficienza epatica acuta-su-cronica rispetto ai controlli sani. Le vescicole non esprimono i marcatori tipici piastrinici (CD41 e CD42b) e monocitari (CD14) sulla loro superficie ma esprimono il marcatore dell'epitelio attivato da piastrine (CD62E). I livelli di CD62E sono significativamente elevati nei pazienti con insufficienza eparica acuta-su-cronica rispetto ai controlli sani e ai pazienti con cirrosi compensata (p=0,0041 e p=0,0111, rispettivamente). I livelli di CD40L sono significativamente elevati in tutti i gruppi di pazienti rispetto ai controlli sani (p<0,02). Le EVs isolate dei pazienti con insufficienza epatica acuta-su-cronica hanno un effetto citotossico superiore rispetto a quelle dei controlli sani e dei pazienti con cirrosi compensata nelle RTC (p<0,0001). Le cellule incubate con le EVs da pazienti con scompenso acuto in cirrosi e insufficienza epatica acuta-su-cronica vanno incontro ad apoptosi (p<0,0001), a produzione massiccia di ROS (p<0,0001), alla perdita della capacità di internalizzare l'albumina (p<0,0001) e alla riduzione dell'espressione di Zonula Occludens-1 (ZO-1) (p=0,0166) rispetto ai soggetti sani e ai pazienti con cirrosi compensata. Non si osserva invece un cambiamento nell'espressione cellulare di megalina e PGC1α. Conclusioni: Il ruolo delle EVs nella cirrosi scompensata necessita di essere approfondito perché potrebbero rappresentare il veicolo su cui viaggiano i mediatori del danno d’organo extraepatico.

Background: Influenza is an important global cause of morbidity and mortality. Though some cardiac complications of influenza, such as myocarditis, are well-recognised, its role as a trigger for acute cardiovascular events is less clear. Improved understanding of this relationship will add to evidence to support appropriate prevention and treatment strategies. Methods: I investigated evidence that influenza and acute respiratory infections could trigger acute myocardial infarction (AMI) through a systematic literature review and meta-analysis (chapter 2) and original research studies (chapters 3-7). These were an ecological weekly time series study using Poisson regression models adjusted for temporal and environmental confounders in England & Wales and Hong Kong (chapter 3); two self-controlled case series analyses using the General Practice Research Database linked to influenza surveillance data (chapter 4) and to cardiac disease registry and hospitalisation data (chapter 5); a case control study in AMI patients and surgical controls during the 2009 influenza pandemic in London (chapter 6); an exploratory mechanistic study (chapter 7). Key findings: • Acute respiratory infections, and seasonal influenza, triggered AMI • A triggering effect may be greater for influenza than for other respiratory infections (p=0.011) • AMI risk was highest in the first three days after acute infection – adjusted incidence ratio 4.19 (95% CI 3.18-5.53) – and persisted for around 28 days • The proportion of AMI deaths due to seasonal influenza ranged from 3-5%, rising to 13% in periods of highest influenza circulation • The relative risk of AMI after acute respiratory infection was highest in people aged ≥80 years • Influenza vaccination protected against some adverse cardiac outcomes in people with existing cardiovascular disease Conclusions: Reducing the burden of influenza would benefit cardiovascular health. Questions remain about key groups to target, as well as the optimal type and delivery of interventions to reduce influenza-associated AMI risk.

An injury to the cervical region of the spinal cord can cause paralysis affecting all four limbs, termed tetraplegia. People with tetraplegia also have paralysis or impaired function of the major respiratory muscles, namely the diaphragm and intercostal and abdominal muscles. This often reduces respiratory function, with associated respiratory complications a leading cause of morbidity and mortality for this population. Abdominal Functional Electrical Stimulation (AFES), the application of electrical pulses to the abdominal muscles causing them to contract, has been shown to improve respiratory function in tetraplegia. Despite these positive results, further work is needed to establish AFES as a standard clinical treatment. The aim of this thesis is to support the clinical introduction of AFES. This was achieved by addressing two primary objectives. Firstly, the development of new technologies and protocols to optimise AFES for use in a clinical setting. Secondly, the clinical evaluation of these technologies and protocols with tetraplegic patients. For research purposes, AFES has typically been applied manually, requiring an operator to synchronise stimulation with respiratory activity. One important step necessary for the clinical introduction of AFES is the development of an automated AFES device that can apply stimulation in synchrony with the users respiratory activity, with different stimulation parameters applied for different breath types such as a quiet breath and a cough. In this thesis, the signal from a non-intrusive respiratory effort belt, worn around the chest, was used to develop a statistical classifcation algorithm capable of classifying respiratory activity in real-time, and applying AFES in synchrony with the user's respiratory activity. The effectiveness of AFES can also be enhanced by stimulating at the abdominal muscle motor points. In this thesis the positions of the abdominal motor points were located systematically for the frst time, in ten able bodied and five tetraplegic participants. To aid the clinical introduction of AFES it is necessary to establish the patient groups who would benefit most from this intervention, and to develop appropriate clinical protocols. This is addressed in two clinical studies, where the feasibility and effectiveness of AFES to improve the respiratory function of the acute ventilator dependant and sub-acute tetraplegic populations was demonstrated. In the first study, conducted with 10 acute ventilator dependant tetraplegics, AFES was applied on alternate weeks for a total duration of eight weeks. This resulted in acute improvements in breathing and led to a longitudinal increase in respiratory function over the study duration. It was found that participants weaned from mechanical ventilation on average 11 days faster than matched historic controls. Previous work, which investigated the effect of a three week AFES training programme on the respiratory function of people with sub-acute tetraplegia, suggested that an extended AFES training programme may be more effective. In the second clinical study in this thesis, a continuous eight week AFES training protocol (combined with a six week control period) was evaluated with three sub-acute tetraplegic participants. The application of AFES led to an acute increase in respiratory function, with a longitudinal improvement in respiratory function observed throughout the study. In a single participant case study, the feasibility of combining AFES with assisted coughing delivered by mechanical insufflation-exsufflation was demonstrated for the first time. This was shown to lead to an acute improvement in respiratory function at six of the eight assessment sessions, indicating that this technique could be used to aid secretion removal. This thesis highlights the feasibility and effectiveness of AFES to improve the respiratory function of the acute ventilator dependant and sub-acute tetraplegic populations. The clinical protocols that enable AFES to be used with these patient groups, and the technological developments detailed throughout this thesis, are an important step towards the introduction of AFES as a regular treatment modality.

The overarching aim of this PhD thesis is to develop methods, which will ultimately improve the management of patients with acute kidney injury (AKI). Over the years one inherent problem in both diagnosing AKI clinically and reviewing and comparing studies published in the literature has been the numerous definitions used to define AKI. 87 With now accepted definitions of AKI, the first question raised was to determine the true impact of AKI, in terms of incidence and outcomes, for both the patient (morbidity and mortality) and the healthcare economy. A retrospective observational database study was performed from secondary care in East Kent (adult catchment population of 582,300). All adult patients (18 years or over) admitted between 1st February 2009 and 31st July 2009, were included. Patients receiving chronic renal replacement therapy (RRT), maternity and day case admissions were excluded. AKI was defined by the acute kidney injury network (AKIN) criteria. A time dependent risk analysis with logistic regression and Cox regression was used for the analysis of in-hospital mortality and survival. The incidence of AKI in the 6 month period was 15,325 pmp/yr (adults) (69% AKIN1, 18% AKIN2 and 13% AKIN3). In-hospital mortality, length of stay and ITU utilisation all increased with severity of AKI. Patients with AKI had an increase in care on discharge and an increase in hospital readmission within 30 days.  In comparison with patients with no AKI those with AKI stage 1 had a 52% longer length of stay (LOS) in hospital, a 2.8-fold increased risk of admission to the intensive therapy unit (ITU), a 39% longer ITU stay (in those who went to ITU), and a 2.4-fold greater in-hospital mortality. Furthermore, patients with AKI stage 1 had twice the long-term risk of death, a 33% higher likelihood of an increase in care, and a 42% higher risk of re-admission within 30 days. In those patients with AKI stage 3 (the subject of the NCEPOD report) 100 hospital LOS doubled, there was a 22 times higher risk of admission to ITU and ITU LOS was also doubled, consistent with national data from the Intensive Care National Audit and Research Centre. A further study using this data in collaboration with Marion Kerr (health economist) at the Department of Health, suggested the annual number of excess inpatient deaths, with AKI in England may be greater than 40,000, 106 and the annual cost of AKI-related inpatient care in England is estimated at £1.02 billion. 106 With the problem now evident and clearly defined, the first stage in improving management was to alert clinicians to the presence of AKI as soon as possible to allow early recognition and intervention. Here the development of a static AKI alert report delivered to the critical care outreach team and specialist renal team is documented. A qualitative analysis was then used to explore the effect of professional interactions, information sharing, and personal and professional characteristics on the use of electronic clinical information and clinical decision support. Key areas highlighted in the qualitative analysis included real-time delivery of AKI alerts, clear responsibility of care to be with the clinical teams with advice from the critical care outreach nurses and renal consultants as required, and improved communication with the clinical teams looking after the patients. This work informed a development partnership with a commercial company (Careflow Connect Limited) to deliver real-time alerting of acute kidney injury to clinicians at the point of care and allow collaboration within the clinical team and also with the specialist renal and critical care outreach teams. However, in any disease process, while we can optimise our measures in place (as above) to alert to the presence of a disease (in this case acute kidney injury (AKI)) and manage it effectively and efficiently at recognition, the ultimate form of treatment is the prevention of the disease occurring in the first place. Hence, in order to achieve this we need to determine the patient at risk. Firstly, potential risk factors were explored. Three time points were also defined where significant clinical decision making takes place and at which points the use of risk models would have greatest impact on clinical care and patient management. These were the point of admission to hospital to guide renal function testing and inform admission planning, and secondly, at 24 hours after admission, often on the post-take ward round to highlight patients who are likely to develop new or worsening AKI if already present, in the first 72 hours of hospital admission so that appropriate management decisions can be made on the ward round. The study population included hospital admissions to the three acute hospitals of East Kent Hospitals University NHS Foundation Trust (EKHUFT) in 2011, excluding maternity and elective admissions. For validation in a second population the study included hospital admissions to Medway NHS Foundation Trust. The study developed and assessed traditional methods to provide risk models for the prediction of new or worsening AKI in patients presenting to hospital and in their management within the first 24 hours of admission. Ordinal logistic regression with uni-variable analyses were used to inform the development of multi-variable analyses. Backward selection was used to retain only statistically significant variables in the final models. The models were validated using actual and predicted probabilities, Area Under the Receiver Operating Characteristic (AUROC) curve analysis and the Hosmer Lemeshow test. The analysis identified key variables which predict AKI both at admission and 72 hours post admission. Validation demonstrated area under ROC of 0.75 and 0.68 respectively. Predicting worsening AKI during admission was unsuccessful. These models were also re-defined with use of the NHS England algorithm to define AKI which produced similar results with area under ROC of 0.73 and 0.67 respectively. The work reported here has demonstrated the significant morbidity and mortality both long and short term of patients who experience acute kidney injury managed in hospital and has developed methods of alerting the presence of AKI to the point of care in real-time to ensure efficient intervention with an aim to improve these outcomes. Qualitative work has also highlighted the complexity regarding the implementation and delivery of alerting systems to the clinical front line. The work reported in this thesis has also demonstrated that routinely available data can be used to highlight patients at risk of acute kidney injury both at the point of admission to hospital and following admission.

La incidencia de la ansiedad, depresión, epilepsia, esclerosis múltiple, estrés patológico, así como otras enfermedades relacionadas con el estrés, ha aumentado significativamente en los últimos años, probablemente debido los cambios drásticos en el modo de vida actual. Según la OMS, los problemas tanto sociales como médicos asociados al estrés están claramente en aumento, afectando seriamente la salud mental y el bienestar no sólo de adultos, sino también de jóvenes y niños. Actualmente hay una mayor conciencia respecto al estrés, precisamente por la importancia que tiene desde el punto de vista médico, social y económico; pero también por las grandes lagunas de conocimiento que aún existen en todas las patologías y trastornos relacionados con el estrés. Es por ello que el estrés se ha convertido en una de las líneas de investigación de gran interés. Sin embargo, a pesar de los esfuerzos realizados, no existe aún un método de medición científicamente validado, repetible y que pueda ser utilizado en la vida cotidiana. Una medida objetiva y fiable del nivel de estrés, podría ser utilizada para comparar la severidad del nivel de estrés en diferentes individuos o entre diferentes grupos de profesionales. Sería, además una herramienta crucial para la prevención, diagnóstico y tratamiento del estrés que ayudaría también en el estudio de muchas otras comorbilidades relacionadas. El estrés puede definirse como la alteración del equilibrio homeostático ante una amenaza específica para el cuerpo (estresor). En este sentido, el estrés no es más que la respuesta de defensa del individuo ante la amenaza percibida. La respuesta del estrés provoca diferentes reacciones fisiológicas en el cuerpo al trata de lidiar con el estresor. Estas reacciones se resumen de manera general como cambios en el sistema nervioso autónomo, una respuesta hormonal (eje suprarrenal adrenal) y un cambio de comportamiento y/o disminución de las capacidades cognitivas. Los métodos que se han propuesto hasta hoy para medir los diferentes aspectos que abarca el estrés dada su naturaleza multidimensional, se pueden agrupar en tres grupos: cuestionarios psicométricos, marcadores bioquímicos y marcadores fisiológicos. Aunque las muestras bioquímicas y los cuestionarios psicométricos son comúnmente utilizados como marcadores de estrés, los mismos no permiten una evaluación continua, ni siquiera regular del estrés. La hipótesis de esta tesis doctoral es que el nivel de respuesta del estrés ante un estresor psicológico puede determinarse a partir de un conjunto de parámetros fisiológicos, que pueden ser medidos de forma no invasiva y continuada. Por lo tanto, la metodología y el análisis de resultados presentados en esta tesis se centran en cuantificar objetivamente distintos componentes fisiológicos de la respuesta del estrés, entendiéndose como cuan cerca o lejos está un individuo de su estado de equilibrio homeostático. Con este fin, se desarrolló un estudio experimental para cuantificar el estrés psicológico y agudo en jóvenes sanos utilizando biomarcadores obtenidos de señales fisiológicas, que puedan medirse de forma continua y no invasiva. Se indujo un estrés agudo en 40 voluntarios aplicándoles una modificación del Test de Estrés Social de Trier (TSST), que es un protocolo ampliamente utilizado y bien documentado para inducir estrés en laboratorio. Se utilizaron test psicológicos estandarizados y marcadores bioquímicos de estrés como la referencia de los niveles de estrés inducido. Se propuso un enfoque multivariable para la medición del estrés, que incluyó, como biomarcadores de estrés, parámetros derivados de la temperatura cutánea periférica (manos) y central (mejilla), la variabilidad de la frecuencia cardíaca y el fotopletismograma de pulso. Los resultados obtenidos muestran que, en las condiciones dadas, el estrés puede ser evaluado cuantitativamente y continuamente a partir de biomarcadores obtenidos de manera no invasiva. Ya que se pudo realizar una medición continua del estrés cada un minuto. Así, basándose en este enfoque, podría surgir un método de monitoreo del estrés en un futuro cercano. Finalmente, a partir de los resultados del estudio experimental y la revisión bibliográfica, se propone un conjunto de requerimientos y directrices para el desarrollo de un sistema de medida del estrés, delineando las especificaciones del sistema para monitorearlo en la vida cotidiana. Este estudio también aborda algunas consideraciones claves y retos a enfrentar este campo.
The incidents of anxiety, depression, epilepsy, multiple sclerosis, pathological stress, as well as other different stress related diseases have significantly increased in recent years and it is most probably due to dramatic changes in the daily lifestyle of citizens. The social and medical problems associated to stress are clearly on the rise and seriously affecting mental health and wellbeing not only in adults but also in young adults and children, according to the WHO (World Health Organization). There is currently an increased awareness of stress, specifically with regards to its medical, social and economic importance; and also, because there are several stress-related comorbidities that remain largely understudied. Therefore, stress has become one of the significant focal points of research interest. Despite the efforts made, a scientifically supported, repeatable and usable in daily life measurement method of stress is still not available. An objective and reliable measurement of stress level could be used to compare the level of stress’ severity in different individuals or between different sets of professionals. It would also be a crucial tool for the prevention, diagnosis and treatment of several diseases. Stress can be defined as the disturbance of the homeostatic balance when facing a specific threat to the body (a stressor) that provokes a stress response. The stress response is the body’s attempt to deal with the stressor triggering the different reactions that can be broadly summarised as changes in the autonomous nervous system, a hormonal response (adrenal pituitary adrenal axis) and a behavioural change and/or a decrease in cognitive skills. The methods that have been proposed until now for measuring the different aspects of stress considering its multidimensional quality, can be gathered in three groups: psychometric tests, biochemical markers, and physiological markers. Although biochemical samples and psychometric questionnaires are commonly used stress markers, they do not allow continuous or even regular stress assessment. Therefore, the hypothesis of this PhD thesis is that the stress response level due to a psychological stressor can be determined from a set of physiological parameters, which can be noninvasively and continuously measured. Consequently, the methodology and analysis of results presented are focused on objectively quantifying the physiological component of the stress response level, which can be understood as how close or far an individual is from his/her state of homeostatic balance. To this end, an experimental study was developed to quantify acute psychological stress in healthy young people using biomarkers from physiological signals, which can be continuously and noninvasively measured. An acute stress response was induced to 40 volunteers by applying a modification of the Trier Social Stress Test (TSST), a widely used and documented protocol for lab-induced stress. Standard psychological tests and biochemical stress markers were used as references for stress levels. A multivariable approach to stress measurement is proposed, which includes as stress biomarkers features derived from finger and face temperature, heart rate variability and pulse photoplethysmogram. The results obtained show that, under the given conditions, stress can be assessed and measured quantitatively and continuously from noninvasive biomarkers, as continuous stress measurement was performed every 1 minute. Based on this approach, a stress monitoring method could emerge in the near future. Finally, based on the findings from the experimental study and literature review presented in this thesis, a set of guidelines for the development of a stress measurement system were suggested to delineate the specifications for a stress monitoring system in daily life conditions. Also, some key considerations and challenges of this emerging area of study are addressed.

The initial chapters of this thesis describe the clinical and physiological aspects of hypoglycaemia, followed by a review of the literature on the effects of acute hypoglycaemia on cognitive function. The subsequent chapters describe original research studies in subjects with and without diabetes, which examine the effects of acute hypoglycaemia on aspects of cognitive function and the prevention of hypoglycaemia. In Studies 1 to 3, a hyperinsulinemic glucose clamp was used to either maintain euglycemia (blood glucose 4,5 mmol/l) or induce hypoglycaemia (2.6 mmol/l) in both healthy adults (n=20), and subjects with type 1 diabetes (n=16). A cognitive test battery was administered to examine aspects of attention, intelligence, motivation, affect and subjective cognition. Hypoglycaemia induced a significant deterioration in tests sensitive to both visual and auditory selective attention, and attentional flexibility deteriorated (Studies 1 and 2). Intelligence scores did not deteriorate during hypoglycaemia (Studies 1 and 2). In Study 3, hypoglycaemia increased task-irrelevant interference and self-focus of attention, but motivation declined to a similar extent during both study conditions. Hypoglycaemia produced a negative mood state with a significant fall in energy levels and a concomitant rise in anxiety (Study 3). Study 4 was an open-label, comparative study of the post-prandial glucodynamics of insulin lispro, when administered either 5 minutes before or 20 minutes after a high fat/high solid phase meal, in twelve subjects with type 1 diabetes. Administration of insulin lispro after the meal reduced the risk of early postprandial hypoglycaemia, without compromising postprandial glycaemic control. Therefore, the work in this thesis has demonstrated a different deterioration of attentional function in humans during hypoglycaemia with no effect on non-verbal reasoning skills. Furthermore, it would appear that the brain is not only less cognitively competent and more dysphoric during hypoglycaemia, it is also more self-aware and distracted when required to perform effortful processing.

This series of studies investigated affective responses to acute exercise. Studies examined the role of affect in predicting V02max, the temporal patterning of affective responses to acute bouts of exercise, and explored some individual differences which may predict .affective responses to different exercise intensities. With a sedentary male population, the first study assessed the validity of predicting V 02max in a sedentary male population during perceptually regulated trials on a cycle ergometer, and the ability of the Feeling Scale (FS) to add to the prediction of V02max. Participants successfully regulated exercise intensity in a relatively consistent manner and FS was able to account for additional variance in the prediction of V02max during trial 1, RPE range 9-17. FS responses followed previously found patterns and became more negative as exercise intensity increased. The temporal pattern of affective responses became the focus of Studies 2 and 4. Study 2 explored and contrasted the response patterns in heart rate, perceived exertion, perceived activation and affective valence to a graded exercise test in sedentary boys and men. Results showed that boys and men responded in a similar manner to exercise intensity above the ventilatory threshold evn but not below the VT. Study 3 explored the temporal dynamics of affective responses during and after prescribed and self-selected exercise in active young adolescents. During exercise, affective states were least positive in high-intensity exercise. A rebound phenomenon was obserVed across all exercise intensities post-exercise. The fourth study investigated affective responses with sedentary young adolescents, within the framework ofthe dualmode model of affect, and used a two-phase, mixed-method, sequential explanatory .. approach. Quantitative results showed affect was least positive above the VT and more positive in the self-selected condition and below the VT. Qualitative results showed positive affective responses were associated with perceived ability to cope,. perceptions of competence, and a positive interpretation of the exercise intensity. The [mal study examined the utility of the Preference for and Tolerance of the Intensity of Exercise Questionnaire (pRETIE-Q) with young adolescents, and investigated its construct validity. ConfIrmatory factor analysis did not support the original structure; ,!,;;hortened . ~ questionnaire offerec\ a stronger structure. Only the Tolerance scale of the adapted PRETIE-Q related to affective responses generated during exercise. A discussion of the research fIndings in the thesis are presented along with strengths and limitations of thestudies, conclusions, future directions and the applied implications are suggested with respect to exercise promotion.

On admission to hospital, patients with acute pancreatitis demonstrated increased interleukin-6 and interleukin-8 release but not tumour necrosis factor-α release from isolated PBMCs compared with healthy volunteers. The severity of the disease was not related to the level of cytokine release from a standard cell number. However, the estimated IL-6 and IL-8 release per unit of blood was greater in those patients with severe disease compared with those with mild disease. Severe disease is also characterised by a more prolonged duration of increased pro-inflammatory cytokine release compared with patients with mild disease. Products of the cyclo-oxygenase pathway play a down-regulatory role in PBMCs in patients with acute pancreatitis as indomethacin (a cyclo-oxygenase inhibitor) had no significant effect on pro-inflammatory cytokine release by PBMCs isolated from healthy volunteers, but increased IL-6 and IL-8 release by PBMCs isolated from patients with both mild and severe disease. PBMC pro-inflammatory cytokine release remains sensitive to the down-regulatory action of the T-cell regulatory cytokines, interleukin-4 and interleukin-10. Lymphocyte proliferation is impaired in acute pancreatitis and correlates with the severity of the disease. Following the successful isolation and culture of human umbilical vein endothelial cells, IL-4 and IL-10 (in contrast to their inhibitory action on PBMCs), produce a dose dependent increase in endothelial cell IL-6 and IL-8 release. TNFα is often detectable in patients with acute pancreatitis on admission, even in severe disease. However, elevation in the serum concentration of soluble TNFα receptors would suggest significant TNFα-induced inflammation early in the course of the disease. Glutamine is a conditionally essential amino acid in patients with severe acute pancreatitis and is important for immune function. A double blind, randomised controlled trial of glutamine supplemented versus conventional total parenteral nutrition in patients with severe acute pancreatitis demonstrated a trend towards improved lymphocyte proliferation in the glutamine supplemented group. Furthermore, PBMC IL-8 release but not TNFα and IL-6 release was significantly reduced over the study period.

Abstract This thesis measures safety climate in a sample of Scottish acute hospitals. It demonstrates how staff perceptions related to safety issues are linked to their safety behaviours and also to the consequences, both for the workers and the patients. Following a review of the industrial and healthcare safety climate literatures, a theoretical model was proposed to investigate the underlying mechanisms between safety climate and safety outcomes. Based on this review, the Hospital Survey on Patient Safety Culture (HSOPSC) was selected as part of a questionnaire to measure safety climate, safety behaviours and safety outcomes. A total of 1969 clinical staff from seven Scottish acute NHS hospitals were surveyed. The psychometric analysis, using EFA and CFA, showed that the original 12 factor structure of the HSOPSC scale was replicated. A focus group study (n = 25) was conducted in two of the hospitals to extend the survey findings. The qualitative data supported the theoretical model proposed based on the literature review by demonstrating the role of managerial practices on safety-related issues. The group discussions further contributed to a wider conceptualization of safety culture by illustrating the multi-level perspective of staff on safety-related issues, including both the external influences and the individual factors. Using structural equation modelling on the same quantitative data set, managerial aspects of safety climate were examined in relation to safety outcomes (safety behaviours, worker and patient outcomes). Results demonstrated the effects of managerial commitment to safety at hospital and unit level on safety outcomes. It also showed the intervening role of safety compliance and safety participation between supervisory practices and self-reported injuries, both for workers and patients. Overall, this thesis provided a psychometrically robust safety climate measurement tool tested in Scottish acute hospitals, and showed the influence of safety-related managerial activities at different levels of the organization on safety outcomes for workers and patients separately.

The clinical management of severe acute pancreatitis has improved significantly in the last decade, mainly due to advances in supportive critical care. However, it still poses formidable problems to the clinician, due to lack of uniformity in early disease definition, absence of disease specific treatment and paucity of evidence base for management of complications. This thesis attempts to address these problems using inter-related studies based on clinical (cohort study and randomised control trial), experimental and data-analysis methodologies.

Moderate physical activity and snack intake suppress the appetite of obese and lean women acutely. The associations between circulating leptin and appetite-satiety ratings suggest that there is some physiological involvement of leptin in short-term appetite regulation in response to physical activity-induced factors but only in obese women. The exercise-related factors considered in this thesis as possible mediators of leptin action were catecholamines, fatty acids, glucose and insulin. Adrenaline is unlikely to be the exercise factor responsible for the coupling between leptin and satiety since adrenaline infusion stimulated an increase in subsequent energy intake in obese women. Labetalol decreased circulating FFA and increased glucose concentrations, which confirms at least b-adrenoceptor blockade. Any conclusion with respect to the a- adrenoceptor blockade should be drawn with caution since labetalol, an a/b blocker, has greater affinity for b- than a-adrenoceptors. No differences in appetite/satiety sensations were found following exercise with adrenoceptor blockade compared to exercise alone. This indicates that the observed anorexic effect of exercise on appetite in obese women was not mediated by b-adrenoceptors. Noradrenaline is another possible exercise factor that could mediate the coupling between leptin and appetite in obese women since it is known that leptin and noradrenaline (NA) have common hypothalamic targets (e.g. NPY) and their effects are mediated by a-1 adrenoceptors. Labetalol probably was not a sufficiently strong a-adrenoceptor blocker to investigate such effects. A study of a more selective a1-adrenoceptor antagonist might be helpful in the investigation of the interaction between leptin and NA in the regulation of eating. Study 4: In endurance-trained athletes a short term detraining increases postprandial plasmin leptin, induces insulin resistance but has no effect on appetite/satiety ratings. The results of the present studies implicate leptin, insulin, insulin resistance and noradrenergic factors in the control of eating following exercise and detraining.

This thesis presents a series of clinical studies on neuroprotective drugs in both volunteers and stroke patients, and assesses the current methodology of clinical trials in stroke. Previous therapeutic trials in stoke have often been inadequate due to small numbers of patients and lack of robust outcome criteria. Overview analyses have not appreciated differences amongst impairment scales developed for clinical trials. Stroke scales are relevant to outcome and may provide surrogate end-points in exploratory trials. In three volunteer studies with the non-competitive NMDA antagonist aptiganel hydrochloride (CNS 1102), the side effect profile resembled that of other NMDA ion channel blocking drugs. The pharmacokinetics and effects upon cerebral blood flow of this drug are favourable for further trials. Magnesium sulphate is the endogenous blocker of the NMDA ion channel, and does not cause the central nervous symptoms of NMDA antagonists. In studies in both volunteers and stroke patients, no adverse haemodynamic or antiplatelet effects were observed. Another neuroprotective drug, the use-dependent sodium channel blocker 619C89, has significant side effects in stroke patients, both as a series of discrete infusions or by continuous infusion over 72 hours. However, until clinical benefit is shown with a neuroprotective drug, it will remain necessary to seek confirmation that potentially therapeutic agents active pharmacologically achieve concentrations in the brain, and side effects are inevitable.

Primary Intracerebral haemorrhage is a severe form of stroke with poor prognosis attributed to haematoma characteristics. High blood pressure is present during the acute phase of intracerebral haemorrhage and associated with poor outcome in part through expansion of haematoma. Data from the ‘Efficacy of Nitric Oxide in Stroke trial’ (ENOS) was used to analyse the performance characteristics of qualitative and quantitative descriptors of intracerebral haematoma. The results showed that formal measurement of haemorrhage characteristics and visual estimates are reproducible. Intracerebral haemorrhage volumes measured using the modified ABC/2 formula were significantly lower compared to standard ABC/2 and computer assisted semi-automatic segmentation. In 629 patients with intracerebral haemorrhage presenting within 48 hours, the effect of blood pressure lowering with transdermal glyceryl trinitrate was assessed. Glyceryl trinitrate lowered blood pressure, was safe but did not improve functional outcome. In a small group of patients treated within 6 hours, glyceryl trinitrate improved functional outcome. Analysis of 246 patients with acute intracerebral haemorrhage from ENOS was undertaken to assess whether there were any differences in functional outcome among those who continued prior antihypertensive drugs during the immediate stroke period compared to those assigned to stop temporarily for 7 days. The results were neutral indicating that there was no benefit in those who continued treatment. Data of 1,011 patients with intracerebral haemorrhage in hyperacute trials from the VISTA collaboration showed differences in baseline characteristics and functional outcomes among patients from various ethnic backgrounds. A systematic review was updated to assess the effect of 26 randomised controlled trials that aimed to alter blood pressure within one week of acute stroke. The results showed that blood pressure reduction did not improve functional outcome irrespective of stroke type. When examined by time, treatment within 6 hours appeared to benefit but the number of patients were small and more studies are needed. The analysis also showed that continuing prestroke antihypertensive drugs in the immediate period after stroke did not benefit and might be harmful. In summary, this thesis provides new information on parameters used to estimate intracerebral haematoma, relationship between management of blood pressure and outcomes after haemorrhagic stroke. The work supports testing of whether very early blood pressure lowering after ictus is beneficial as is being undertaken in ongoing randomised controlled trials. Adjusting for ethnic differences may further identify patients in whom treatment may confer measurable advantage.

Introduction For some people, ageing is associated with the experience of increased co-morbidity, functional impairment, poor resilience and heightened vulnerability to external stressors, resulting in reduced lifespan as well as health-span. This frailty phenomenon poses challenges to health care systems in the form of increased patient complexity and resource utilisation. The acute care setting, characterised by time-pressure and high patient turn-over, is under strain and struggles to recognise and subsequently reliably intervene, to prevent, reverse or halt the decline of this vulnerable cohort. Methods This mixed-methods study probes existing evidence and ‘real-world’ processes with a systematic review of frailty assessments developed or validated in the acute care setting and a survey of contemporaneous clinical practice in London Acute Medical Units. Content validation and understanding of contextual factors for ideal frailty assessment in acute care is explored using Delphi consensus and Focus Group methodology respectively. The resultant model is developed on existing retrospective national Hospital Episode Statistics data, and prospectively tested on observational data in a local Acute Medical Unit setting. Results Existing frailty scores are preponderantly biophysical in nature, and have poor predictive power for adverse outcomes in the acute care setting. In clinical practice, single-dimension assessment tools predominate. Frailty syndromes and previous high resource utilisation in the form of a simple, clinically relevant tool useful to the multidisciplinary team gain consensus as optimal assessment for the setting. Retrospective testing of the frailty model displays moderate predictive powers for adverse events (inpatient mortality, emergency readmission and institutionalisation) and prospective testing provides concurrent (Frailty Index, Age, Co-Morbidity) and comparative predictive validity (Frailty Index, Co-Morbidity, admission National Early Warning Score) with existing risk stratification models in this setting. Conclusions A risk prediction model based on frailty syndromes and previous high resource utilisation is a valid, feasible and useful for the acute care setting.

Acute myocardial infarction (AMI) results in the activation of the innate immune system with monocytes playing critical roles in both the initial inflammation following myocardial ischaemia and subsequent recovery. Monocytes are a heterogeneous cell population and observations from experimental models demonstrate that immediately following myocardial injury, classical inflammatory monocytes, which are highly phagocytic, are recruited to ischaemic myocardium from the bone marrow and spleen and peak at 48 hours. This is followed by the recruitment of non-classical monocytes that are involved in repair and healing, peaking at day 5. The monocyte response in humans following AMI is currently poorly understood. Due to their central role in the pathogenesis of AMI, monocytes are attractive both as potential biomarkers to inform of extent of myocardial injury (and recovery) and also as therapeutic targets with the specific targeting of monocytes in experimental models resulting in reduced infarction size and improved LV remodelling. However, in spite of these promising results and our greater understanding of the pathogenesis of AMI, no immune-modulating therapeutic has been translated into routine clinical practice. We therefore hypothesized that characterisation of the monocyte response to AMI by flow cytometry and gene expression profiling in both experimental models and humans would give novel insights into underlying biological processes and function (both locally in the myocardium and systemically), identify novel therapeutic targets, enable their use as cellular biomarkers of disease, and test conservation between species validating the experimental model for future investigation. Classical inflammatory monocytes were found to significantly increase in the peripheral blood 48 hours following AMI in both mice and humans, with the magnitude of the monocyte response correlating with the extent of myocardial injury in both species. Gene expression profiling of peripheral circulating monocytes following AMI identified a number of candidate genes, biological pathways and upstream regulators that were conserved between species and that could represent novel therapeutic targets. Furthermore, in an experimental model of AMI, leukocytes appeared to have effects beyond the ischaemic myocardium, with leukocyte recruitment in remote myocardium and in kidneys associated with elevated inflammatory markers and endothelial activation.

Acute liver failure (ALF) is a devastating condition with a high associated mortality rate. Paracetamol hepatotoxicity remains the leading cause of ALF in the developed world. The studies outlined in this thesis explore the current management of ALF, and systematically review the prognostic tests currently used in paracetamol-induced ALF. Using a database of over 900 acute liver injury patients, the impact of unintentional paracetamol overdose is retrospectively analysed, demonstrating a strong association between this mode of paracetamol overdose and adverse clinical outcomes, including the requirement for emergency orthotopic liver transplantation. Current prognostic tests for severe paracetamol-induced hepatotoxicity have been criticised for their relatively low sensitivity, with the result that not all patients who might benefit from tertiary level care are identified. This thesis demonstrates that the development of the Systemic Inflammatory Response Syndrome (SIRS) or extrahepatic organ failure is strongly associated with death following paracetamol overdose. Due to their very high sensitivity in this condition, both the SIRS and Sequential Organ Failure Assessment scores have potential as future gatekeepers to improve the triage of paracetamol overdose patients, thereby delivering tertiary level care to those most likely to require emergency transplantation. A greater understanding of the pathophysiological links between the initial hepatic injury and development of the SIRS could help to identify novel biomarkers for ALF, and help guide future therapeutic avenues. Using serum samples from a prospectively collected cohort of acute liver injury patients, this thesis identifies two novel biomarkers, serum ferritin and the long pentraxin PTX3, which show a strong association with outcome following paracetamol hepatotoxicity. These biomarkers illustrate the importance that the innate immune system plays in the pathogenesis of paracetamol-induced ALF, and identifies several exciting areas for future cellular and animal-based studies.

Acute intestinal infections - a large group of human infectious diseases caused by pathogenic and opportunistic bacteria, viruses and protozoa. Intestinal infections until now occupy a leading position in infectious diseases, especially in childhood, second in incidence only to influenza and acute respiratory infections. Registered in the world each year to 1-1.2 billion diarrheal diseases, about 5 million children die each year from intestinal infections and their complications. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/33574

Acute myocarditis is an acute inflammatory syndrome characterized by myocardial damage and dysfunction often due to a viral infection followed by a variable development over time. There are currently no specific treatments and standard treatments for heart failure are generally applied. The inflammasome is a recently identified macromolecular structure that occupies a central role in the amplification of the inflammatory response and promotion of cell death during acute and chronic infections. We hypothesized the formation of the inflammasome in acute myocarditis. To investigate, samples of patients were collected from the Cardiomyopathy Registry in Trieste, with 12 cases of biopsy-proven myocarditis and 11 cases of autopsy-proven myocarditis stained for major components of the inflammasome through immunofluorescence; 10 of the 12 (83.3%) biopsy cases and 8 of the 11 (72.7%) autopsy cases presented formation of the inflammasome in a variety of cells including resident cells (i.e. cardiomyocytes, endothelial cells, fibroblasts) and infiltrating cells (i.e. leukocytes) while varying in intensity and distribution. Control samples of 5 subjects not presenting with any acute cardiac events showed no formation of the inflammasome. While further studies should look to elucidate the correlation of inflammasome-formation and progression of disease, this finding paves the way for further insight into the pathophysiology of acute myocarditis.

Background: Acute pancreatitis (AP) has a mortality of 30% in severe cases. Major causes worldwide are gallstones and alcohol misuse. The first aim was to characterise the aetiology, epidemiology and outcomes for patients with AP in Western Sydney (WS). The second aim was to explore pathogenesis of AP and identify potential biomarkers of severe AP using RNA sequencing. Methods: 1) A retrospective cohort analysis of 932 patients with AP presenting to 4 tertiary hospitals in WS was performed. Data from medical records was analysed using SPSS software 2) A RNA sequencing study was performed in a separate cohort of 84 patients with AP (mild=55, moderately severe=19, severe=10) from 2 tertiary hospitals in WS. RNA sequencing was performed on peripheral venous blood collected within 24h of presentation to hospital and data analysis conducted using DESeq2 and Ingenuity Pathway Analysis software. Results: The majority of patients had gallstone AP (40%). 11.1% had severe AP and mortality was 1%. Females were less likely to develop severe AP. There was a failure to comply with guidelines for early management of AP. RNA sequencing identified 1914 differentially expressed genes (DEG) in severe AP compared to moderately severe and mild AP. Lipocalin 2, IL10 and olfactomedin 4 are potential biomarkers for severe AP and pathways dysregulated in severe AP had immunological and mitochondrial functions. There were 1468 DEG between females and males with AP and pathways unique to females were involved in B cell function. There were no DEG between the different aetiological groups. Conclusion: The majority of patients have mild AP with a low risk of mortality. T cell suppression and mitochondrial dysfunction are important pathways in severe AP. We demonstrated clear differences in the pathophysiology of AP between genders, with women demonstrating up-regulation of B cell functions. The differences in clinical outcomes between genders in AP may be due to underlying immune system differences.

Chronic neuropathic pain occurring after an operation is a common problem, however little data is available describing the nature or prevalence of acute neuropathic pain following surgery. In this thesis, I explore the measurement scale properties of a commonly used neuropathic pain screening tool, and use this tool to describe the prevalence of acute and chronic neuropathic pain following thoracic surgery. I also explore how best to diagnose acute neuropathic pain with a Delphi survey of expert opinion and confirmatory observational cohort study. The results show that the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) neuropathic pain screening tool demonstrates acceptable fit to the Rasch measurement model in the chronic postoperative pain population, but only has reliability consistent with use at a group level. Using this tool, I demonstrate that 8% of thoracic surgery patients experience acute neuropathic pain an average of 3 days after surgery, with 22% developing neuropathic pain by 3 months. Experiencing acute neuropathic pain significantly increased the odds of developing chronic neuropathic pain (odds ratio 7.7 [95% confidence interval 1.5-39.7]). A Delphi survey of specialists identified 9 items considered important in the diagnosis of acute neuropathic pain, and suggests that unlike diagnosis in the chronic pain population, a poor response to opioid medications was an important indicator of neuropathic pain. Preliminary results from a matched cohort study confirm this, by demonstrating that verbal descriptors of neuropathic pain are significantly more common in patients with poorly controlled postoperative pain despite strong opioid use.

Acute lymphoblastic leukemia (ALL) is a neoplasia characterized by an abnormal, clonal and self-maintaining proliferation of lymphoid cells. In this three year of phd I tried to add some information to understand the complex molecular mechanisms underlying this disease. I performed my studies in the laboratory of "Oncoematologia Pediatrica, Dipartimento di Pediatria dell'Università  degli studi di Padova" and for three months in the laboratory of Prof. A. A. Ferrando, Columbia University, Irving Cancer Center, New York. The recombination, insertion and deletion of immunoglobulin (Ig) and T cell receptors (TCR) gene segments results in an individual gene sequence unique for each lymphocytes, named N-region. This genes junctional-region can be considered a fingerprint-marker specific of each lymphocytes and, consequentially, of each lymphoid neoplasia. It can be used to study the biological characteristics of leukemia or to analyze the minimal residual disease (MRD). The initial period of my Phd has been dedicated to the study of the t(4;11) positive ALL, in 32 children above the age of 1 year through the survival, immunophenotype and Ig/TCR pattern analysis. Immunophenotype data in t(4;11)-positive ALL from children 1 year or older demonstrate a more mature pattern of IGH rearrangements as compared to infant cases as like as the more mature age goes with a more mature lymphocyte (Chapter 1.1). Fundamental for the Ig/TCR analysis is to have enough exordia DNA to execute the panel of screening PCR. The screening of diagnosis DNA is hampered by lack of fresh material and consequent limited amount of genomic DNA available. We evaluate the possibility to perform the Ig/TCR screening starting from unstained glass slide smear of cells from bone marrow aspirate or from extracted small amount of DNA after a whole genome amplification with ?29 polymerase and random primers. We execute 476 PCR before and after the whole genome amplification. Results of PCR analysis, confirmed sequencing the PCR products, have a concordance of 98%. No false-positive results were obtained by PCR analysis after whole genome amplification (Chapter 1.2). The main topic of my Phd studies have been the prognostic value of MRD analysis in relapsed pediatric ALL patients. The treatment of ALL in children has improved over the last decades, nevertheless, disease recurrence remains the leading cause of treatment failure in the 20% of patients. In the AIEOP LAL REC2003 protocol, relapsed patient are stratified in class of risk: low-medium (S1-S2) and high risk (S3-S4) based on immunophenotype, time and site of relapse. We evaluate the prognostic value of MRD during the therapeutic treatment in high risk relapsed patients. We studied 60 relapsed patients classified in S3-S4, treated with AIEOP REC2003 protocol. The Ig/TCR clonal profile have been studied with screening PCR and homo-heteroduplex analysis in each patient; the MRD have been exanimate with RQ-PCR in different time-point during therapy: (TP1) after induction, (TP2) after re-induction, (TP3) and after consolidation after relapse. At three year, the EFS is 73, 45 and 19% respectively for patients with TP1 negative, positive not quantifiable (MRD < 10-4) or positive (MRD ? 10-4), (p < 0.05). The statistical significance of MRD predictive prognostic value have been confirmed by multivariate analysis. In high-risk relapsed patients we demonstrated that MRD evaluation was able to identify patients who cold benefit from the chemotherapy treatment and subset of patients who seem not to benefit from further consolidations, including allogenic HSCT (Chapter 2.1). Medullary (BM) relapse is currently defined still according to morphological criteria, when a blast count ? 25% is detected in a bone marrow sample after the achievement of complete remission. We evaluate the clinical significance of MRD monitoring in ALL pediatric patients as an indicator of impending hematological disease recurrence and determinate the critical levels of MRD which can predict relapse. The cumulative incidence of relapse in case of detection of positive and quantifiable MRD finding resulted 85.7%. The value is statistically significant in prediction when compared with the presence of a MRD negative or positive below the quantitative range. The prior identification of MRD as an signal of subsequent morphological hematological relapse could help to decide for a preventive chemotherapeutic treatment (Chapter 2.1). To understand the way to develop new therapeutic treatment for patient with high-risk characteristics, we embrace the hypothesis that a rare cancer stem cell population would be the origin of many malignant neoplasy, responsible of the growth, diffusion and resistance to treatment of tumor, providing a key target for novel curative therapies. In ALL patients this sub-population has not been clearly identify and characterized, anyway recent studies move the attention to the subpopulations characterized by surface antigens CD34/CD38/CD19. We analyzed the Ig/TCR clonal profile of CD34+CD38-CD19+ and CD34+CD38-CD19- subpopulations after sorting, comparing with the Ig/TCR pattern of patients' unsorted blasts. In 9/10 patients the subpopulations of progenitors, isolated and analyzed, share with total blast cells at least one specific clonal rearrangement (finger-print marker). This is a direct demonstration, through a genetic marker and not though a functional assay, of the origin fo blast cell from the subpopulation CD34+CD38-, in the 90% of cases from the sub-fraction CD34+CD38-CD19- (Chapter 3.1). We also studied the correlation between the frequency of CD34+CD38- at the diagnosis of ALL and the level of MRD after treatment. We analyzed 133 ALL patients finding and statistical significant association between the percentage of CD34+CD38- <1% and a low level of MRD at day 33 of chemotherapy (Chapter 3.1). During the last period of the phd I approached the study of WT1, a transcription factor important for normal cellular development and cell survival. The molecular mechanisms involved in disease progression and recurrence of T-ALL are poorly understood. Starting from the observation that in the 10% of T-ALL patients WT1 is mutated, the attention move toward it with genetic and proteomic studies to comprehend its involvement in the development of leukemia. My contribute concerned the study of WT1 gene promoter methylation status (Chapter 4.1).
La leucemia linfoblastica acuta (LLA) è una neoplasia caratterizzata da una proliferazione abnorme, clonale ed auto-mantenuta di cellule linfoidi. In questi tre anni di dottorato ho cercato di aggiungere qualche nozione per la comprensione dei complessi meccanismi molecolari che sottendono a questa malattia. L'attività  di ricerca si è svolta presso il Laboratorio di Oncoematologia Pediatrica, Dipartimento di Pediatria dell'Università  degli Studi di Padova e per tre mesi presso il Laboratorio del Prof. A. A. Ferrando, Columbia University Irving Cancer Research Center, New York. Ogni linfocita è contraddistinto a livello dei siti di ricombinazione, inserzione e delezione dei segmenti genici delle regioni variabili delle immunoglobuline (Ig) e del recettore delle cellule T (TCR), da una regione giunzionale detta N-region. Le regioni giunzionali possono essere considerate un fingerprint-marker specifico di ogni linfocita e di ogni neoplasia linfoide ed essere utilizzate per studiare le caratteristiche biologiche della leucemia o per l'analisi della malattia residua minima (MRD). I primi mesi di dottorato sono stati dedicati allo studio della LLA positiva per t(4;11) in 32 pazienti pediatrici di età  superiore a 1 anno attraverso l'analisi dell'immunofenotipo, riarrangiamenti Ig/TCR e prognosi. Dall'analisi è stato identificato un pattern di riarrangiamenti diverso tra i pazienti pediatrici e gli infant dovuto alla diversa maturità  della cellula nelle due classi di pazienti come se la maggiore età  dei pazienti andasse a pari passo con lo stadio maturativo del blasto leucemico (Capitolo 1.1). Fondamentale per l'analisi dei riarrangiamenti Ig/TCR è la disponibilità di materiale per l'estrazione del DNA e l'esecuzione del pannello di PCR di screening. Se si ha una quantità limitata di DNA non è quindi sempre possibile ricavare il pattern di clonalità . Abbiamo eseguito uno studio per valutare la possibilità di eseguire le PCR di screening della regione Ig/TCR su DNA amplificato con una tecnica di "whole genome amplification" basata sull'utilizzo della DNA polimerasi ?29 e di random primer. Il DNA utilizzato era estratto da cellule in sospensione di asiprato midollare, anche in quantità limitata, o da cellule su vetrino non colorato. Abbiamo eseguito 476 PCR prima e dopo "whole genome amplification". Il confronto dei risultati, dopo sequenziamento dei prodotti di PCR, ha mostrato una concordanza dei risultati del 98%. L'amplificazione dell'intero genoma non ha inficiato i risultati di PCR nella regione Ig/TCR (Capitolo 1.2). Il principale campo di interesse in questi anni di dottorato è stata lo studio del valore prognostico della MRM nei pazienti pediatrici LLA ricaduti. La quasi totalità dei pazienti pediatrici con leucemia linfoblastica acuta raggiunge la remissione completa continua ma esiste ancora un 20% di questi che va incontro ad una recidiva di malattia. Il protocollo AIEOP LAL REC 2003 stratifica i pazienti ricaduti in classi di rischio: basso-medio (S1-S2) e alto (S3-S4) a seconda dell'immunofenotipo, del tempo e della sede di ricaduta. Abbiamo valutato il valore prognostico della malattia residua minima durante la terapia nella classe di pazienti ad alto rischio. Sono stati studiati 60 pazienti ricaduti classificati come S3-S4, arruolati nel protocollo AIEOP LAL REC 2003. Per ogni paziente E' stato analizzato il profilo di clonalità  con PCR di screening e l'analisi heteroduplex dei riarrangiamenti Ig/TCR; è stata analizzata la malattia residua minima (MRM) attraverso RQ-PCR in diverse fasi della terapia: dopo l'induzione (TP1), dopo la re-induzione (TP2) e dopo il consolidamento (TP3) post-ricaduta. L'EFS a tre anni è del 73, 45 e 19% rispettivamente per i pazienti con MRD al TP1 negativa, positiva non quantificabile (MRD < 10-4) o positivo (MRD ? 10-4), (P < 0.05). Il valore prognostico predittivo statisticamente significativo dell'MRD è stato confermato dall'analisi multivariata. Abbiamo dimostrato che la quantificazione delle malattia residua minima permette di differenziare i pazienti precocemente e in modo efficace comprendendo quali pazienti rispondono alla terapia convenzionale e possano ricevere il trapianto di cellule staminali allogeniche e quali invece necessitino di terapie innovative (Capitolo 2.1). La ricaduta midollare è attualmente definita secondo criteri morfologici quando la conta dei blasti è ?25% dopo che il paziente ha raggiunto la remissione completa. Abbiamo valutato il potere della presenza di MRM come indicatore di successiva ricorrenza ematologica di ALL determinando se vi siano livelli critici di MRM predittivi di ricaduta. Abbiamo trovato che rilevare un prelievo positivo quantificabile durante il follow-up del paziente è associato a una cumulative relapse incidence dell'85.7%. Questo dato ha valore statisticamente significativo se confrontato con il valore predittivo di un prelievo negativo o positivo non quantificabile per MRM. Identificare anticipatamente la ricaduta potrebbe aiutare nel progettare un trattamento terapeutico preventivo di ricaduta morfologica (Capitolo 2.1). Nella prospettiva di comprendere su quali vie si potrebbero spostare le future strategie terapeutiche per pazienti che presentino caratteristiche di alto rischio, abbiamo abbracciato l'ipotesi attuale che l'origine di molte neoplasie maligne risieda in una ristretta popolazione di cellule staminali tumorali responsabile della crescita, diffusione tumorale e resistenza alla terapia. Nella LLA questa popolazione non è stata ancora chiaramente identificata e caratterizzata anche se studi recenti spingono l'attenzione sulle subpopolazioni caratterizzate dagli antigeni di superficie CD34/CD38/CD19. Abbiamo analizzato in 10 pazienti il profilo di clonalità  Ig/TCR delle popolazioni CD34+CD38-CD19+ e CD34+CD38-CD19- dopo sorting, confrontandolo con quello identificato nella popolazione totale dei blasti leucemici del paziente. In 9/10 pazienti le subpopolazioni di progenitori, isolate e analizzate, condividevano almeno un riarrangiamento genico clonale (fingerprint- marker) con i blasti leucemici. Questa è una dimostrazione diretta, attraverso un marcatore genetico, e non funzionale, dell'origine del blasti leucemici dalla popolazione CD34+CD38-, nel 90% dei casi nella sottopolazione CD34+CD38-CD19- (Capitolo 3.1). Abbiamo inoltre studiato se la frequenza del compartimento CD34+CD38- all'esordio LLA correlasse con il livello di MRM dopo chemioterapia. Abbiamo analizzato 133 pazienti LLA rilevando che una percentuale <1% di CD34+CD38- correla in modo statisticamente significativo con un basso livello di MRM rilevato dopo 33 giorni di terapia (Capitolo 3.1). Durante gli ultimi mesi di dottorato mi sono avvicinata allo studio di WT1, un fattore di regolazione dello sviluppo. I meccanismi molecolari implicati nello sviluppo e nella ricaduta della LLA ad immunofenotipo T sono scarsamente compresi. Partendo dall'osservazione che nel 10% dei pazienti con LLA-T il gene WT1 è mutato, abbiamo approcciato lo studio di questo fattore dal punto di vista genico e proteico, per comprendere il suo coinvolgimento nello sviluppo della leucemia. La parte del lavoro a cui ho contribuito ha riguardato l'analisi dello stato di metilazione del promotore del gene WT1 (Capitolo 4.1).

La síndrome de distrés respiratori agut (ARDS) és una insuficiència respiratòria aguda amb una incidència global a Europa de 17,9 per cada 100.000 persones-any. Tot i els avenços en el tractament de suport dels pacients amb ARDS, la mortalitat continua sent alta (40%) i els pacients que sobreviuen presenten seqüeles persistents. Actualment no existeix un tractament efectiu. La fisiopatologia de l’ARDS es caracteritza per l’activació de la coagulació i la inflamació a nivell pulmonar, juntament amb el trencament de la barrera alveolar-capil·lar. Això comporta la formació d’edema proteic, la infiltració dels neutròfils cap al compartiment alveolar i l'activació dels macròfags cap a un fenotip pro-inflamatori. Estudis previs en models pre-clínics de lesió pulmonar aguda (ALI) i en pacients amb ARDS han demostrat els efectes beneficiosos del anti-coagulants, tot i que aquests efectes positius es veuen contrarestats pel risc d’hemorràgia sistèmica. Els anti-coagulants podrien ser efectius gràcies a la seva activitat anti-inflamatòria a més de les seves propietats anti-coagulants. Atesa l’estreta interacció entre aquestes vies i la seva influència en la permeabilitat, els anti-coagulants també podrien restaurar la barrera alveolar-capil·lar. La nebulització dels anti-coagulants directament al compartiment alveolar podria augmentar l'eficàcia local i disminuir el risc d'hemorràgia sistèmica. La hipòtesi d'aquesta tesi és que l'heparina nebulitzada i/o antitrombina (ATIII) limitaran la resposta pro-inflamatòria i pro-coagulant pulmonar després de la LPA, promovent, també, la restauració de la barrera alveolar-capil·lar. La co-administració dels anti-coagulants directament als pulmons mitjançant nebulització produirà un efecte sinèrgic que potenciarà les propietats de l'heparina i l’ATIII, reduint la lesió pulmonar i evitant el risc d'hemorràgia sistèmica. Com a part d’aquesta tesi es mostren els resultats de l'acció de l'heparina o l’ATIII específicament en poblacions pulmonars primàries de cèl·lules humanes lesionades i l'administració directa d'heparina i/o ATIII als pulmons per nebulització en un model de rata d’ALI. La nebulització d'heparina i/o d’ATIII atenuen la inflamació i coagulació pulmonar sense produir hemorràgia sistèmica en el model d’ALI. El tractament amb heparina nebulitzada modula els macròfags alveolars mitjançant la reducció dels efectors de TGF-β i NF-κB i la via de coagulació i disminueix el reclutament de neutròfils a l'espai alveolar. L'administració local d'ATIII augmenta els efectes beneficiosos en la coagulació, mentre que la combinació d'ATIII i heparina tenen un major impacte en la reducció de la permeabilitat i la disminució de la infiltració de macròfags en el compartiment alveolar. En estudiar l'acció translacional en humans d'ambdós anti-coagulants en poblacions cel·lulars humanes lesionades aïllades de biòpsies pulmonars, l'heparina disminueix l'expressió de marcadors proinflamatoris en els macròfags alveolars i desactiva la via NF-κB en cèl·lules alveolars tipus II; disminuint l'expressió dels seus mediadors i efectors. D’altra banda, l'ATIII redueix els nivells de mediadors proinflamatoris i augmenta les unions estretes en les cèl·lules alveolars tipus II lesionades. Els estudis actuals demostren que l'heparina nebulitzada i l'ATIII poden ser un tractament potencial per a la ARDS, ja que actuen en diferents vies i processos de la fisiopatologia d’aquesta síndrome. L'administració local d'anti-coagulants atenua la lesió pulmonar disminuint la inflamació, la coagulació i proveeix millores en la permeabilitat sense causar hemorràgia sistèmica.
Acute respiratory distress syndrome (ARDS) is an acute respiratory failure with a global incidence in Europe of 17.9 per 100,000 person-year. Although significant advances have been performed in supportive care of patients with ARDS, mortality remains high (40%) and survivors present persistent sequelae. An effective pharmacological therapy for this syndrome is not available yet. ARDS pathophysiology involves pulmonary activated coagulation and inflammation together with the breakdown of the alveolar-capillary barrier. This leads to proteinaceous edema, neutrophils infiltration into the alveolar compartment and the activation of macrophages towards a pro-inflammatory phenotype. Beneficial effects of anti-coagulants have been proved in pre-clinical models of acute lung injury (ALI) and in ARDS patients, although systemic bleeding offset its positive effects. Anti-coagulants could be effective for their anti-inflammatory activity in addition to their anti-coagulant properties. Moreover, given the cross talk of these pathways and their influence on permeability, anti-coagulants could also restore the alveolar-capillary barrier. Nebulization of anti-coagulants directly into the alveolar compartment might increase local efficacy and decrease the risk of systemic bleeding. The hypothesis of this thesis is that nebulized heparin and/or antithrombin (ATIII) limit the pro-inflammatory and pro-coagulant response in the lungs after ALI, also promoting the restoration of the alveolar-capillary barrier. The co-administration of both anti-coagulants directly into the lungs via nebulization produces a synergistic effect enhancing the properties of heparin and ATIII, reducing lung injury and avoiding the risk of systemic bleeding. As part of this thesis we are showing the results of the action of heparin or ATIII in specific primary human injured cell lung populations and the direct administration of heparin and/or ATIII into the lungs by nebulization in a rat model of ALI. Nebulized heparin and/or ATIII attenuated pulmonary inflammation and coagulation and did not produce systemic bleeding in the model of ALI. Treatment with nebulized heparin modulated alveolar macrophages through reducing TGF-β and NF-κB effectors and the coagulation pathway and decreased the recruitment of neutrophils into the alveolar space. Local administration of ATIII alone increased beneficial effects in coagulation, while combined ATIII and heparin had a higher impact reducing permeability and decreasing the infiltration of macrophages into the alveolar compartment. The translational action into humans of both anti-coagulants was also studied. In injured human cell lung populations isolated from lung biopsies, heparin diminished the expression of pro-inflammatory markers in alveolar macrophages and deactivated the NF-κB pathway in alveolar type II cells; decreasing the expression of its mediators and effectors. Also, ATIII decreased levels of pro-inflammatory mediators and increased levels of tight junctions in injured alveolar type II cells. The current studies prove that nebulized heparin and ATIII might be a potential treatment for ARDS, as they act in different pathways and processes of the pathophysiology of this syndrome. Local administration of anti-coagulants attenuates lung injury decreasing inflammation, coagulation and proving ameliorations on permeability without causing systemic bleeding.

Acute lung injury (ALI) and it’s more severe form, acute respiratory distress syndrome (ARDS), are conditions characterised by neutrophilic pulmonary inflammation, refractory hypoxaemia and diffuse alveolar damage. This work reports on the first UK based prospective study of the incidence and longer term mortality of ALI/ARDS in a general intensive care unit. Results reveal significant under recognition of this condition, which occurred in 12.5% of the ICU population (n=344). Hospital and 2 year mortality rates were 50-55% and 58-61% respectively. Neutrophils are central in the pathogenesis of ALI/ARDS. Neutrophil priming, a reversible process whereby the response of neutrophils to an activating stimulus is up-regulated by prior exposure to a priming agent, is a pre-requisite for neutrophil-mediated tissue damage. Comparisons of the trans-pulmonary gradient of several markers of neutrophil priming were made in different patient groups. Patients with sepsis but healthy lungs (n=6) were found to have a positive trans-pulmonary gradient with respect to neutrophil expression of CD62L, suggesting that CD62L ‘low’ (primed) neutrophils are being de-primed in the pulmonary circulation. In patients with ARDS this gradient was reversed, suggesting that neutrophils are being primed within the lung. This leads to the novel hypothesis that, in conditions such as sepsis, neutrophils primed systemically may be held in the pulmonary capillary bed and there allowed to de-prime, before being released in a quiescent state. Failure of this process may allow net accumulation of primed neutrophils in the lung with consequent lung injury. Currently there are no effective pharmacological therapies for ALI/ARDS, which is compounded by the relative lack of human models. An 18 month, prospective study of the incidence of ALI/ARDS post oesophagectomy revealed an incidence of 31% and suggested intra-operative one lung ventilation as a causative factor. Hence, patients undergoing oesophagectomy present an attractive model for future ALI/ARDS research.

Thesis (Doctoral)--Departments of Surgical Pathophysiology and Anaesthesiology, University of Lund, University Hospital MAS.
Added t.p. with thesis statement inserted. Summary in Swedish. Includes bibliographical references.