22 resultados para Predictive Monitoring

em Helda - Digital Repository of University of Helsinki


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The Taita Hills in southeastern Kenya form the northernmost part of Africa’s Eastern Arc Mountains, which have been identified by Conservation International as one of the top ten biodiversity hotspots on Earth. As with many areas of the developing world, over recent decades the Taita Hills have experienced significant population growth leading to associated major changes in land use and land cover (LULC), as well as escalating land degradation, particularly soil erosion. Multi-temporal medium resolution multispectral optical satellite data, such as imagery from the SPOT HRV, HRVIR, and HRG sensors, provides a valuable source of information for environmental monitoring and modelling at a landscape level at local and regional scales. However, utilization of multi-temporal SPOT data in quantitative remote sensing studies requires the removal of atmospheric effects and the derivation of surface reflectance factor. Furthermore, for areas of rugged terrain, such as the Taita Hills, topographic correction is necessary to derive comparable reflectance throughout a SPOT scene. Reliable monitoring of LULC change over time and modelling of land degradation and human population distribution and abundance are of crucial importance to sustainable development, natural resource management, biodiversity conservation, and understanding and mitigating climate change and its impacts. The main purpose of this thesis was to develop and validate enhanced processing of SPOT satellite imagery for use in environmental monitoring and modelling at a landscape level, in regions of the developing world with limited ancillary data availability. The Taita Hills formed the application study site, whilst the Helsinki metropolitan region was used as a control site for validation and assessment of the applied atmospheric correction techniques, where multiangular reflectance field measurements were taken and where horizontal visibility meteorological data concurrent with image acquisition were available. The proposed historical empirical line method (HELM) for absolute atmospheric correction was found to be the only applied technique that could derive surface reflectance factor within an RMSE of < 0.02 ps in the SPOT visible and near-infrared bands; an accuracy level identified as a benchmark for successful atmospheric correction. A multi-scale segmentation/object relationship modelling (MSS/ORM) approach was applied to map LULC in the Taita Hills from the multi-temporal SPOT imagery. This object-based procedure was shown to derive significant improvements over a uni-scale maximum-likelihood technique. The derived LULC data was used in combination with low cost GIS geospatial layers describing elevation, rainfall and soil type, to model degradation in the Taita Hills in the form of potential soil loss, utilizing the simple universal soil loss equation (USLE). Furthermore, human population distribution and abundance were modelled with satisfactory results using only SPOT and GIS derived data and non-Gaussian predictive modelling techniques. The SPOT derived LULC data was found to be unnecessary as a predictor because the first and second order image texture measurements had greater power to explain variation in dwelling unit occurrence and abundance. The ability of the procedures to be implemented locally in the developing world using low-cost or freely available data and software was considered. The techniques discussed in this thesis are considered equally applicable to other medium- and high-resolution optical satellite imagery, as well the utilized SPOT data.

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Background: The fecal neutrophil-derived proteins calprotectin and lactoferrin have proven useful surrogate markers of intestinal inflammation. The aim of this study was to compare fecal calprotectin and lactoferrin concentrations to clinically, endoscopically, and histologically assessed Crohn’s disease (CD) activity, and to explore the suitability of these proteins as surrogate markers of mucosal healing during anti-TNFα therapy. Furthermore, we studied changes in the number and expression of effector and regulatory T cells in bowel biopsy specimens during anti-TNFα therapy. Patients and methods: Adult CD patients referred for ileocolonoscopy (n=106 for 77 patients) for various reasons were recruited (Study I). Clinical disease activity was assessed with the Crohn’s disease activity index (CDAI) and endoscopic activity with both the Crohn’s disease index of severity (CDEIS) and the simple endoscopic score for Crohn’s disease (SES-CD). Stool samples for measurements of calprotectin and lactoferrin, and blood samples for CRP were collected. For Study II, biopsy specimens were obtained from the ileum and the colon for histologic activity scoring. In prospective Study III, after baseline ileocolonoscopy, 15 patients received induction with anti-TNFα blocking agents and endoscopic, histologic, and fecal-marker responses to therapy were evaluated at 12 weeks. For detecting changes in the number and expression of effector and regulatory T cells, biopsy specimens were taken from the most severely diseased lesions in the ileum and the colon (Study IV). Results: Endoscopic scores correlated significantly with fecal calprotectin and lactoferrin (p<0.001). Both fecal markers were significantly lower in patients with endoscopically inactive than with active disease (p<0.001). In detecting endoscopically active disease, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for calprotectin ≥200 μg/g were 70%, 92%, 94%, and 61%; for lactoferrin ≥10 μg/g they were 66%, 92%, 94%, and 59%. Accordingly, the sensitivity, specificity, PPV, and NPV for CRP >5 mg/l were 48%, 91%, 91%, and 48%. Fecal markers were significantly higher in active colonic (both p<0.001) or ileocolonic (calprotectin p=0.028, lactoferrin p=0.004) than in ileal disease. In ileocolonic or colonic disease, colon histology score correlated significantly with fecal calprotectin (r=0.563) and lactoferrin (r=0.543). In patients receiving anti-TNFα therapy, median fecal calprotectin decreased from 1173 μg/g (range 88-15326) to 130 μg/g (13-1419) and lactoferrin from 105.0 μg/g (4.2-1258.9) to 2.7 μg/g (0.0-228.5), both p=0.001. The relation of ileal IL-17+ cells to CD4+ cells decreased significantly during anti-TNF treatment (p=0.047). The relation of IL-17+ cells to Foxp3+ cells was higher in the patients’ baseline specimens than in their post-treatment specimens (p=0.038). Conclusions: For evaluation of CD activity, based on endoscopic findings, more sensitive surrogate markers than CDAI and CRP were fecal calprotectin and lactoferrin. Fecal calprotectin and lactoferrin were significantly higher in endoscopically active disease than in endoscopic remission. In both ileocolonic and colonic disease, fecal markers correlated closely with histologic disease activity. In CD, these neutrophil-derived proteins thus seem to be useful surrogate markers of endoscopic activity. During anti-TNFα therapy, fecal calprotectin and lactoferrin decreased significantly. The anti-TNFα treatment was also reflected in a decreased IL-17/Foxp3 cell ratio, which may indicate improved balance between effector and regulatory T cells with treatment.

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Matrix metalloproteinase (MMP) -8, collagenase-2, is a key mediator of irreversible tissue destruction in chronic periodontitis and detectable in gingival crevicular fluid (GCF). MMP-8 mostly originates from neutrophil leukocytes, the first line of defence cells which exist abundantly in GCF, especially in inflammation. MMP-8 is capable of degrading almost all extra-cellular matrix and basement membrane components and is especially efficient against type I collagen. Thus the expression of MMP-8 in GCF could be valuable in monitoring the activity of periodontitis and possibly offers a diagnostic means to predict progression of periodontitis. In this study the value of MMP-8 detection from GCF in monitoring of periodontal health and disease was evaluated with special reference to its ability to differentiate periodontal health and different disease states of the periodontium and to recognise the progression of periodontitis, i.e. active sites. For chair-side detection of MMP-8 from the GCF or peri-implant sulcus fluid (PISF) samples, a dip-stick test based on immunochromatography involving two monoclonal antibodies was developed. The immunoassay for the detection of MMP-8 from GCF was found to be more suitable for monitoring of periodontitis than detection of GCF elastase concentration or activity. Periodontally healthy subjects and individuals suffering of gingivitis or of periodontitis could be differentiated by means of GCF MMP-8 levels and dipstick testing when the positive threshold value of the MMP-8 chair-side test was set at 1000 µg/l. MMP-8 dipstick test results from periodontally healthy and from subjects with gingivitis were mainly negative while periodontitis patients sites with deep pockets ( 5 mm) and which were bleeding on probing were most often test positive. Periodontitis patients GCF MMP-8 levels decreased with hygiene phase periodontal treatment (scaling and root planing, SRP) and even reduced during the three month maintenance phase. A decrease in GCF MMP-8 levels could be monitored with the MMP-8 test. Agreement between the test stick and the quantitative assay was very good (κ = 0.81) and the test provided a baseline sensitivity of 0.83 and specificity of 0.96. During the 12-month longitudinal maintenance phase, periodontitis patients progressing sites (sites with an increase in attachment loss ≥ 2 mm during the maintenance phase) had elevated GCF MMP-8 levels compared with stable sites. General mean MMP-8 concentrations in smokers (S) sites were lower than in non-smokers (NS) sites but in progressing S and NS sites concentrations were at an equal level. Sites with exceptionally and repeatedly elevated MMP-8 concentrations during the maintenance phase were clustered in smoking patients with poor response to SRP (refractory patients). These sites especially were identified by the MMP-8 test. Subgingival plaque samples from periodontitis patients deep periodontal pockets were examined by polymerase chain reaction (PCR) to find out if periodontal lesions may serve as a niche for Chlamydia pneumoniae. Findings were compared with the clinical periodontal parameters and GCF MMP-8 levels to determine the correlation with periodontal status. Traces of C. pneumoniae were identified from one periodontitis patient s pooled subgingival plaque sample by means of PCR. After periodontal treatment (SRP) the sample was negative for C. pneumoniae. Clinical parameters or biomarkers (MMP-8) of the patient with the positive C. pneumoniae finding did not differ from other study patients. In this study it was concluded that MMP-8 concentrations in GCF of sites from periodontally healthy individuals, subjects with gingivitis or with periodontitis are at different levels. The cut-off value of the developed MMP-8 test is at an optimal level to differentiate between these conditions and can possibly be utilised in identification of individuals at the risk of the transition of gingivitis to periodontitis. In periodontitis patients, repeatedly elevated GCF MMP-8 concentrations may indicate sites at risk of progression of periodontitis as well as patients with poor response to conventional periodontal treatment (SRP). This can be monitored by MMP-8 testing. Despite the lower mean GCF MMP-8 concentrations in smokers, a fraction of smokers sites expressed very high MMP-8 concentrations together with enhanced periodontal activity and could be identified with MMP-8 specific chair-side test. Deep periodontal lesions may be niches for non-periodontopathogenic micro-organisms with systemic effects like C. pneumoniae and possibly play a role in the transmission from one subject to another.

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Valko- ja ruskolahosienet tunnetaan luonnossa tehokkaimpina puun ja karikkeen lignoselluloosan lahottajina. Valkolahosienet pystyvät hajottamaan kaikkia puun osia: ligniiniä, selluloosaa ja hemiselluloosaa. Selektiivisesti ligniiniä hajottavat sienet lahottavat puusta suhteessa enemmän vaikeasti hajoavaa ligniiniä kuin selluloosaa tai hemiselluloosaa, jolloin jäljelle jää valkoista ja miltei puhdasta selluloosaa. Bioteknisissä sovelluksissa juuri selektiviiviset valkolahottajat ovat kiinnostavia. Niiden avulla voidaan puuhaketta esikäsitellä esimerkiksi paperinvalmistuksessa haitallisen ligniinin poistamiseksi. Ruskolahosienet ovat huomattavia puun, puutavaran ja puisten rakenteiden lahottajia, kuten tässä työssä käytetty Gloeophyllum trabeum (saunasieni ) ja Poria (Postia) placenta (istukkakääpä). Ruskolahosienet hajottavat puusta hemiselluloosan lisäksi selluloosaa, jolloin jää jäljelle ruskea ja jauhomaiseksi mureneva ligniini. Ruskolahosienet muovaavat ligniiniä jonkin verran. Kahden ruskolahosienen G. trabeumin ja P. placentan lisäksi tutkittiin valkolahosieniä, joista Ceriporiopsis subvermispora (karstakääpä) ja harvinainen Physisporinus rivulosus -sieni (talikääpä) hajottavat ligniiniä erittäin selektiivisesti. Phanerochaete chrysosporium on kaikkialla paljon tutkittu sieni, ja Phlebia radiata valkolahosientä (rusorypykkä) on tutkittu paljon mikrobiologian osastolla. Lisäksi tutkittiin Phlebia tremellosa -sienten (hytyrypykkä) ligninolyyttisten entsyymien tuottoa ja 14C-leimatun synteettisen ligniinin (DHP) hajotusta. P. radiata ja P. tremellosa -sienten on todettu aiemmin hajottavan ligniiniä selektiivisesti. Työssä selvitettiin miten sienten kasvua voi mitata, miten vertailukelpoisia eri mittaamismenetelmillä saadut tulokset ovat ja ilmenevätkö sienten aktiivisimmat kasvuvaiheet samaan aikaan eri menetelmillä mitattuna. Tärkeimmät tulokset olivat seuraavat havainnot: (i) P. radiata ja P. tremellosa -sienikannat tuottivat ligniini- ja mangaaniperoksidaasientsyymejä (LiP ja MnP) sekä lakkaasia, ja sienistä puhdistettiin 2-3 LiP- ja P. radiatasta yksi MnP-entsyymi; (ii) P. tremellosa -sienet hajottivat leimattua synteettistä ligniiniä (DHP) yhtä hyvin kuin paljon tutkitut P. chrysosporium ja P. radiata -sienet; (iii) puu, sienen luonnollinen kasvualusta, lisäsi valkolaho- ja ruskolahosienten demetoksylaatiota [O14CH3]-leimatusta ligniinin malliyhdisteestä 14CO2:ksi ilman puuta olleeseen alustaan verrattuna; (iv) demetoksylaatio (14CO2:n tuotto) oli normaalissa ilma-atmosfäärissä useimmiten parempi happeen verrattuna; (v) hapessa paras 14CO2:n tuotto saatiin puupalakasvatuksissa, joihin oli lisätty ravinnetyppeä tai typen lisäksi glukoosia sekä valkolaho- että ruskolahosienillä; (vi) ilmassa 14CO2:n tuotto oli puulla voimakkainta valkolahosienillä ilman lisäravinteita, kun taas G. trabeum -sienellä se oli yhtä hyvä eri alustoissa; (vii) biomassan muodostuminen rihmastojen ergosterolipitoisuuksista mitattuna oli ruskolahosienillä parempi kuin valkolahosienillä; (viii) ja biomassojen huippupitoisuudet olivat 6:lla sienellä eri suuruisia ja niiden maksimimäärien ajankohdat vaihtelivat viiden viikon kasvatusten kuluessa. Mikrobiologian osastolla Viikissä eristetty ja paljon tutkittu P. radiata -valkolahosieni oli mukana kaikissa tehdyissä kokeissa. Sienen LiP-aktiivisuus ja 14CO2:n tuotto 14C-rengas-leimatusta synteettisestä ligniinistä (DHP) korreloivat erittäin hyvin. Biomassan muodostuminen ergosterolilla määritettynä tuki hyvin entsyymiaktiivisuusmittauksilla ja isotooppikasvatuksilla saatuja tuloksia.

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Contamination of urban streams is a rising topic worldwide, but the assessment and investigation of stormwater induced contamination is limited by the high amount of water quality data needed to obtain reliable results. In this study, stream bed sediments were studied to determine their contamination degree and their applicability in monitoring aquatic metal contamination in urban areas. The interpretation of sedimentary metal concentrations is, however, not straightforward, since the concentrations commonly show spatial and temporal variations as a response to natural processes. The variations of and controls on metal concentrations were examined at different scales to increase the understanding of the usefulness of sediment metal concentrations in detecting anthropogenic metal contamination patterns. The acid extractable concentrations of Zn, Cu, Pb and Cd were determined from the surface sediments and water of small streams in the Helsinki Metropolitan region, southern Finland. The data consists of two datasets: sediment samples from 53 sites located in the catchment of the Stream Gräsanoja and sediment and water samples from 67 independent catchments scattered around the metropolitan region. Moreover, the sediment samples were analyzed for their physical and chemical composition (e.g. total organic carbon, clay-%, Al, Li, Fe, Mn) and the speciation of metals (in the dataset of the Stream Gräsanoja). The metal concentrations revealed that the stream sediments were moderately contaminated and caused no immediate threat to the biota. However, at some sites the sediments appeared to be polluted with Cu or Zn. The metal concentrations increased with increasing intensity of urbanization, but site specific factors, such as point sources, were responsible for the occurrence of the highest metal concentrations. The sediment analyses revealed, thus a need for more detailed studies on the processes and factors that cause the hot spot metal concentrations. The sediment composition and metal speciation analyses indicated that organic matter is a very strong indirect control on metal concentrations, and it should be accounted for when studying anthropogenic metal contamination patterns. The fine-scale spatial and temporal variations of metal concentrations were low enough to allow meaningful interpretation of substantial metal concentration differences between sites. Furthermore, the metal concentrations in the stream bed sediments were correlated with the urbanization of the catchment better than the total metal concentrations in the water phase. These results suggest that stream sediments show true potential for wider use in detecting the spatial differences in metal contamination of urban streams. Consequently, using the sediment approach regional estimates of the stormwater related metal contamination could be obtained fairly cost-effectively, and the stability and reliability of results would be higher compared to analyses of single water samples. Nevertheless, water samples are essential in analysing the dissolved concentrations of metals, momentary discharges from point sources in particular.

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Farmland bird species have been declining in Europe. Many declines have coincided with general intensification of farming practices. In Finland, replacement of mixed farming, including rotational pastures, with specialized cultivation has been one of the most drastic changes from the 1960s to the 1990s. This kind of habitat deterioration limits the persistence of populations, as has been previously indicated from local populations. Integrated population monitoring, which gathers species-specific information of population size and demography, can be used to assess the response of a population to environment changes also at a large spatial scale. I targeted my analysis at the Finnish starling (Sturnus vulgaris). Starlings are common breeders in farmland habitats, but severe declines of local populations have been reported from Finland in the 1970s and 1980s and later from other parts of Europe. Habitat deterioration (replacement of pasture and grassland habitats with specialized cultivation areas) limits reproductive success of the species. I analysed regional population data in order to exemplify the importance of agricultural change to bird population dynamics. I used nestling ringing and nest-card data from 1951 to 2005 in order to quantify population trends and per capita reproductive success within several geographical regions (south/north and west/east aspects). I used matrix modelling, acknowledging age-specific survival and fecundity parameters and density-dependence, to model population dynamics. Finnish starlings declined by 80% from the end of the 1960s up to the end of the 1980s. The observed patterns and the model indicated that the population decline was due to the decline of the carrying capacity of farmland habitats. The decline was most severe in north Finland where populations largely become extinct. However, habitat deterioration was most severe in the southern breeding areas. The deteriorations in habitat quality decreased reproduction, which finally caused the decline. I suggest that poorly-productive northern populations have been partly maintained by immigration from the highly-productive southern populations. As the southern populations declined, ceasing emigration caused the population extinction in north. This phenomenon was explained with source sink population dynamics, which I structured and verified on the basis of a spatially explicit simulation model. I found that southern Finnish starling population exhibits ten-year cyclic regularity, a phenomenon that can be explained with delayed density-dependence in reproduction.

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Bioremediation, which is the exploitation of the intrinsic ability of environmental microbes to degrade and remove harmful compounds from nature, is considered to be an environmentally sustainable and cost-effective means for environmental clean-up. However, a comprehensive understanding of the biodegradation potential of microbial communities and their response to decontamination measures is required for the effective management of bioremediation processes. In this thesis, the potential to use hydrocarbon-degradative genes as indicators of aerobic hydrocarbon biodegradation was investigated. Small-scale functional gene macro- and microarrays targeting aliphatic, monoaromatic and low molecular weight polyaromatic hydrocarbon biodegradation were developed in order to simultaneously monitor the biodegradation of mixtures of hydrocarbons. The validity of the array analysis in monitoring hydrocarbon biodegradation was evaluated in microcosm studies and field-scale bioremediation processes by comparing the hybridization signal intensities to hydrocarbon mineralization, real-time polymerase chain reaction (PCR), dot blot hybridization and both chemical and microbiological monitoring data. The results obtained by real-time PCR, dot blot hybridization and gene array analysis were in good agreement with hydrocarbon biodegradation in laboratory-scale microcosms. Mineralization of several hydrocarbons could be monitored simultaneously using gene array analysis. In the field-scale bioremediation processes, the detection and enumeration of hydrocarbon-degradative genes provided important additional information for process optimization and design. In creosote-contaminated groundwater, gene array analysis demonstrated that the aerobic biodegradation potential that was present at the site, but restrained under the oxygen-limited conditions, could be successfully stimulated with aeration and nutrient infiltration. During ex situ bioremediation of diesel oil- and lubrication oil-contaminated soil, the functional gene array analysis revealed inefficient hydrocarbon biodegradation, caused by poor aeration during composting. The functional gene array specifically detected upper and lower biodegradation pathways required for complete mineralization of hydrocarbons. Bacteria representing 1 % of the microbial community could be detected without prior PCR amplification. Molecular biological monitoring methods based on functional genes provide powerful tools for the development of more efficient remediation processes. The parallel detection of several functional genes using functional gene array analysis is an especially promising tool for monitoring the biodegradation of mixtures of hydrocarbons.

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Placental abruption, one of the most significant causes of perinatal mortality and maternal morbidity, occurs in 0.5-1% of pregnancies. Its etiology is unknown, but defective trophoblastic invasion of the spiral arteries and consequent poor vascularization may play a role. The aim of this study was to define the prepregnancy risk factors of placental abruption, to define the risk factors during the index pregnancy, and to describe the clinical presentation of placental abruption. We also wanted to find a biochemical marker for predicting placental abruption early in pregnancy. Among women delivering at the University Hospital of Helsinki in 1997-2001 (n=46,742), 198 women with placental abruption and 396 control women were identified. The overall incidence of placental abruption was 0.42%. The prepregnancy risk factors were smoking (OR 1.7; 95% CI 1.1, 2.7), uterine malformation (OR 8.1; 1.7, 40), previous cesarean section (OR 1.7; 1.1, 2.8), and history of placental abruption (OR 4.5; 1.1, 18). The risk factors during the index pregnancy were maternal (adjusted OR 1.8; 95% CI 1.1, 2.9) and paternal smoking (2.2; 1.3, 3.6), use of alcohol (2.2; 1.1, 4.4), placenta previa (5.7; 1.4, 23.1), preeclampsia (2.7; 1.3, 5.6) and chorioamnionitis (3.3; 1.0, 10.0). Vaginal bleeding (70%), abdominal pain (51%), bloody amniotic fluid (50%) and fetal heart rate abnormalities (69%) were the most common clinical manifestations of placental abruption. Retroplacental blood clot was seen by ultrasound in 15% of the cases. Neither bleeding nor pain was present in 19% of the cases. Overall, 59% went into preterm labor (OR 12.9; 95% CI 8.3, 19.8), and 91% were delivered by cesarean section (34.7; 20.0, 60.1). Of the newborns, 25% were growth restricted. The perinatal mortality rate was 9.2% (OR 10.1; 95% CI 3.4, 30.1). We then tested selected biochemical markers for prediction of placental abruption. The median of the maternal serum alpha-fetoprotein (MSAFP) multiples of median (MoM) (1.21) was significantly higher in the abruption group (n=57) than in the control group (n=108) (1.07) (p=0.004) at 15-16 gestational weeks. In multivariate analysis, elevated MSAFP remained as an independent risk factor for placental abruption, adjusting for parity ≥ 3, smoking, previous placental abruption, preeclampsia, bleeding in II or III trimester, and placenta previa. MSAFP ≥ 1.5 MoM had a sensitivity of 29% and a false positive rate of 10%. The levels of the maternal serum free beta human chorionic gonadotrophin MoM did not differ between the cases and the controls. None of the angiogenic factors (soluble endoglin, soluble fms-like tyrosine kinase 1, or placental growth factor) showed any difference between the cases (n=42) and the controls (n=50) in the second trimester. The levels of C-reactive protein (CRP) showed no difference between the cases (n=181) and the controls (n=261) (median 2.35 mg/l [interquartile range {IQR} 1.09-5.93] versus 2.28 mg/l [IQR 0.92-5.01], not significant) when tested in the first trimester (mean 10.4 gestational weeks). Chlamydia pneumoniae specific immunoglobulin G (IgG) and immunoglobulin A (IgA) as well as C. trachomatis specific IgG, IgA and chlamydial heat-shock protein 60 antibody rates were similar between the groups. In conclusion, although univariate analysis identified many prepregnancy risk factors for placental abruption, only smoking, uterine malformation, previous cesarean section and history of placental abruption remained significant by multivariate analysis. During the index pregnancy maternal alcohol consumption and smoking and smoking by the partner turned out to be the major independent risk factors for placental abruption. Smoking by both partners multiplied the risk. The liberal use of ultrasound examination contributed little to the management of women with placental abruption. Although second-trimester MSAFP levels were higher in women with subsequent placental abruption, clinical usefulness of this test is limited due to low sensitivity and high false positive rate. Similarly, angiogenic factors in early second trimester, or CRP levels, or chlamydial antibodies in the first trimester failed to predict placental abruption.

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Septic shock is a common killer in intensive care units (ICU). The most crucial issue concerning the outcome is the early and aggressive start of treatment aimed at normalization of hemodynamics and the early start of antibiotics during the very first hours. The optimal targets of hemodynamic treatment, or impact of hemodynamic treatment on survival after first resuscitation period are less known. The objective of this study was to evaluate different aspects of the hemodynamic pattern in septic shock with special attention to prediction of outcome. In particular components of early treatment and monitoring in the ICU were assessed. A total of 401 patients, 218 with septic shock and 192 with severe sepsis or septic shock were included in the study. The patients were treated in 24 Finnish ICUs during 1999-2005. 295 of the patients were included in the Finnish national epidemiologic Finnsepsis study. We found that the most important hemodynamic variables concerning the outcome were the mean arterial pressures (MAP) and lactate during the first six hours in ICU and the MAP and mixed venous oxygen saturation (SvO2) under 70% during first 48 hours. The MAP levels under 65 mmHg and SvO2 below 70% were the best predictive thresholds. Also the high central venous pressure (CVP) correlated to adverse outcome. We assessed the correlation and agreement of SvO2 and mean central venous oxygen saturation (ScvO2) in septic shock during first day in ICU. The mean SvO2 was below ScvO2 during early sepsis. Bias of difference was 4.2% (95% limits of agreement 8.1% to 16.5%) by Bland-Altman analysis. The difference between saturation values correlated significantly to cardiac index and oxygen delivery. Thus, the ScvO2 can not be used as a substitute of SvO2 in hemodynamic monitoring in ICU. Several biomarkers have been investigated for their ability to help in diagnosis or outcome prediction in sepsis. We assessed the predictive value of N-terminal pro brain natriuretic peptide (NT-proBNP) on mortality in severe sepsis or septic shock. The NT-proBNP levels were significantly higher in hospital nonsurvivors. The NT-proBNP 72 hrs after inclusion was independent predictor of hospital mortality. The acute cardiac load contributed to NTproBNP values at admission, but renal failure was the main confounding factor later. The accuracy of NT-proBNP, however, was not sufficient for clinical decision-making concerning the outcome prediction. The delays in start of treatment are associated to poorer prognosis in sepsis. We assessed how the early treatment guidelines were adopted, and what was the impact of early treatment on mortality in septic shock in Finland. We found that the early treatment was not optimal in Finnish hospitals and this reflected to mortality. A delayed initiation of antimicrobial agents was especially associated with unfavorable outcome.

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The purpose of this study was to evaluate the use of sentinel node biopsy (SNB) in the axillary nodal staging in breast cancer. A special interest was in sentinel node (SN) visualization, intraoperative detection of SN metastases, the feasibility of SNB in patients with pure tubular carcinoma (PTC) and in those with ductal carcinoma in situ (DCIS) in core needle biopsy (CNB) and additionally in the detection of axillary recurrences after tumour negative SNB. Patients and methods. 1580 clinically stage T1-T2 node-negative breast cancer patients, who underwent lymphoscintigraphy (LS), SNB and breast surgery between June 2000 - 2004 at the Breast Surgery Unit. The CNB samples were obtained from women, who participated the biennial, population based mammography screening at the Mammography Screening Centre of Helsinki 2001 - 2004.In the follow- up, a cohort of 205 patients who avoided AC due to negative SNB findings were evaluated using ultrasonography one and three years after breast surgery. Results. The visualization rate of axillary SNs was not enhanced by adjusting radioisotope doses according to BMI. The sensitivity of the intraoperative diagnosis of SN metastases of invasive lobular carcinoma (ILC) was higher, 87%, with rapid, intraoperative immunohistochemistry (IHC) group compared to 66% without it. The prevalence of tumour positive SN findings was 27% in the 33 patients with breast tumours diagnosed as PTC. The median histological tumour size was similar in patients with or without axillary metastases. After the histopathological review, six out of 27 patients with true PTC had axillary metastases, with no significant change in the risk factors for axillary metastases. Of the 67 patients with DCIS in the preoperative percutaneous biopsy specimen , 30% had invasion in the surgical specimen. The strongest predictive factor for invasion was the visibility of the lesion in ultrasound. In the three year follow-up, axillary recurrence was found in only two (0.5%) of the total of 383 ultrasound examinations performed during the study, and only one of the 369 examinations revealed cancer. None of the ultrasound examinations were false positive, and no study participant was subjected to unnecessary surgery due to ultrasound monitoring. Conclusions. Adjusting the dose of the radioactive tracer according to patient BMI does not increase the visualization rate of SNs. The intraoperative diagnosis of SN metastases is enhanced by rapid IHC particularly in patients with ILC. SNB seems to be a feasible method for axillary staging of pure tubular carcinoma in patients with a low prevalence of axillary metatastases. SNB also appears to be a sensible method in patients undergoing mastectomy due to DCIS in CNB. It also seems useful in patients with lesions visible in breast US. During follow-up, routine monitoring of the ipsilateral axilla using US is not worthwhile among breast cancer patients who avoided AC due to negative SN findings.

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Thrombophilia (TF) predisposes both to venous and arterial thrombosis at a young age. TF may also impact the thrombosis or stenosis of hemodialysis (HD) vascular access in patients with end-stage renal disease (ESRD). When involved in severe thrombosis TF may associate with inappropriate response to anticoagulation. Lepirudin, a potent direct thrombin inhibitor (DTI), indicated for heparin-induced thrombocytopenia-related thrombosis, could offer a treatment alternative in TF. Monitoring of narrow-ranged lepirudin demands new insights also in laboratory. The above issues constitute the targets in this thesis. We evaluated the prevalence of TF in patients with ESRD and its impact upon thrombosis- or stenosis-free survival of the vascular access. Altogether 237 ESRD patients were prospectively screened for TF and thrombogenic risk factors prior to HD access surgery in 2002-2004 (mean follow-up of 3.6 years). TF was evident in 43 (18%) of the ESRD patients, more often in males (23 vs. 9%, p=0.009). Known gene mutations of FV Leiden and FII G20210A occurred in 4%. Vascular access sufficiently matured in 226 (95%). The 1-year thrombosis- and stenosis-free access survival was 72%. Female gender (hazards ratio, HR, 2.5; 95% CI 1.6-3.9) and TF (HR 1.9, 95% CI 1.1-3.3) were independent risk factors for the shortened thrombosis- and stenosis-free survival. Additionally, TF or thrombogenic background was found in relatively young patients having severe thrombosis either in hepatic veins (Budd-Chiari syndrome, BCS, one patient) or inoperable critical limb ischemia (CLI, six patients). Lepirudin was evaluated in an off-label setting in the severe thrombosis after inefficacious traditional anticoagulation without other treatment options except severe invasive procedures, such as lower extremity amputation. Lepirudin treatments were repeatedly monitored clinically and with laboratory assessments (e.g. activated partial thromboplastin time, APTT). Our preliminary studies with lepirudin in thrombotic calamities appeared safe, and no bleeds occurred. An effective DTI lepirudin calmed thrombosis as all patients gradually recovered. Only one limb amputation was performed 3 years later during the follow-up (mean 4 years). Furthermore, we aimed to overcome the limitations of APTT and confounding effects of warfarin (INR of 1.5-3.9) and lupus anticoagulant (LA). Lepirudin responses were assessed in vitro by five specific laboratory methods. Ecarin chromogenic assay (ECA) or anti-Factor IIa (anti-FIIa) correlated precisely (r=0.99) with each other and with spiked lepirudin in all plasma pools: normal, warfarin, and LA-containing plasma. In contrast, in the presence of warfarin and LA both APTT and prothrombinase-induced clotting time (PiCT®) were limited by non-linear and imprecise dose responses. As a global coagulation test APTT is useful in parallel to the precise chromogenic methods ECA or Anti-FIIa in challenging clinical situations. Lepirudin treatment requires multidisciplinary approach to ensure appropriate patient selection, interpretation of laboratory monitoring, and treatment safety. TF seemed to be associated with complicated thrombotic events, in venous (BCS), arterial (CLI), and vascular access systems. TF screening should be aimed to patients with repeated access complications or prior unprovoked thromboembolic events. Lepirudin inhibits free and clot-bound thrombin which heparin fails to inhibit. Lepirudin seems to offer a potent and safe option for treatment of severe thrombosis. Multi-centered randomized trials are necessary to assess the possible management of complicated thrombotic events with DTIs like lepirudin and seek prevention options against access complications.