Browsing by Subject "Imaging"

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  • Nieminen, H. J.; Gahunia, H. K.; Pritzker, K. P. H.; Ylitalo, T.; Rieppo, L.; Karhula, S. S.; Lehenkari, P.; Haeggstörm, E.; Saarakkala, S. (2017)
    Objective: Histopathological grading of osteochondral (OC) tissue is widely used in osteoarthritis (OA) research, and it is relatively common in post-surgery in vitro diagnostics. However, relying on thin tissue section, this approach includes a number of limitations, such as: (1) destructiveness, (2) sample processing artefacts, (3 ) 2D section does not represent spatial 3D structure and composition of the tissue, and (4) the final outcome is subjective. To overcome these limitations, we recently developed a contrast-enhanced mu CT (CE mu CT) imaging technique to visualize the collagenous extracellular matrix (ECM) of articular cartilage (AC). In the present study, we demonstrate that histopathological scoring of OC tissue from CE mu CT is feasible. Moreover, we establish a new, semi-quantitative OA mu CT grading system for OC tissue. Results: Pathological features were clearly visualized in AC and subchondral bone (SB) with mu CT and verified with histology, as demonstrated with image atlases. Comparison of histopathological grades (OARSI or severity (0-3)) across the characterization approaches, CE mu CT and histology, excellent (0.92, 95% CI = [0.84, 0.96], n = 30) or fair (0.50, 95% CI = [0.16, 0.74], n = 27) intra-class correlations (ICC), respectively. A new mu CT grading system was successfully established which achieved an excellent cross-method (mu CT vs histology) reader-to-reader intra-class correlation (0.78, 95% CI = [0.58, 0.89], n = 27). Conclusions: We demonstrated that histopathological information relevant to OA can reliably be obtained from CE mu CT images. This new grading system could be used as a reference for 3D imaging and analysis techniques intended for volumetric evaluation of OA pathology in research and clinical applications. (C) 2017 Published by Elsevier Ltd on behalf of Osteoarthritis Research Society International.
  • Afrane, Yaw (Helsingin yliopisto, 2020)
    The world population is growing and is expected to reach over 9 billion in about 30 years. Climate change is also widely expected to worsen famines in certain regions of the world. This will drastically increase global food demand. Food security efforts should be therefore be geared towards promoting food crops that can thrive in these regions and can withstand the condition likely to be brought about by changing climate. Cassava is a typical example of such a crop. This study investigated the use of digital images to estimate growth parameters of young cassava plants. Cassava was cultivated in pots at the University of Helsinki greenhouse at Viikki. The plants were given different water level (100%, 60% and 30% saturation) and potassium (0.1, 1.0, 4.0, 16.0 and 32.0mM) treatments. Digital red-green-blue (RGB) and multispectral images were taken every other week for 5 consecutive times. The images were processed to obtain leaf area, Normalized Difference Vegetation Index (NDVI), and Crop Senescence Index (CSI) and correlated with directly measured growth parameters of the young cassava crops. It was observed that leaf area that was computed from images, and NDVI which was computed from the multispectral images have significant positive correlations with the growth parameters, ie, actual leaf area, chlorophyll content, and plant biomass. CSI however showed weak a correlation between the growth parameters of the young cassava plants. Images leaf area and NDVI were then used to identify the changes in the effects of the water and potassium treatments.
  • Oja, S.; Komulainen, P.; Penttilä, A.; Nystedt, J.; Korhonen, M. (BioMed Central, 2018)
    Abstract Background Senescent cells are undesirable in cell therapy products due to reduced therapeutic activity and risk of aberrant cellular effects, and methods for assessing senescence are needed. Early-passage mesenchymal stromal cells (MSCs) are known to be small and spindle-shaped but become enlarged upon cell aging. Indeed, cell morphology is routinely evaluated during MSC production using subjective methods. We have therefore explored the possibility of utilizing automated imaging-based analysis of cell morphology in clinical cell manufacturing. Methods An imaging system was adopted for analyzing changes in cell morphology of bone marrow-derived MSCs during long-term culture. Cells taken from the cultures at the desired passages were plated at low density for imaging, representing morphological changes observed in the clinical-grade cultures. The manifestations of aging and onset of senescence were monitored by population doubling numbers, expression of p16INK4a and p21Cip1/Waf1, β-galactosidase activity, and telomeric terminal restriction fragment analysis. Results Cell area was the most statistically significant and practical parameter for describing morphological changes, correlating with biochemical senescence markers. MSCs from passages 1 (p1) and 3 (p3) were remarkably uniform in size, with cell areas between 1800 and 2500 μm2. At p5 the cells began to enlarge resulting in a 4.8-fold increase at p6–9 as compared to p1. The expression of p16INK4a and activity of β-galactosidase had a strong correlation with the increase in cell area, whereas the expression of p21Cip1/Waf1 reached its maximum at the onset of growth arrest and subsequently decreased. Mean telomere length shortened at an apparently constant rate during culture, from 8.2 ± 0.3 kbp at p1, reaching 6.08 ± 0.6 kbp at senescence. Conclusions Imaging analysis of cell morphology is a useful tool for evaluating aging in cell cultures throughout the lifespan of MSCs. Our findings suggest that imaging analysis can reproducibly detect aging-related changes in cell morphology in MSC cultures. These findings suggest that cell morphology is still a supreme measure of cell quality and may be utilized to develop new noninvasive imaging-based methods to screen and quantitate aging in clinical-grade cell cultures.
  • Oja, S.; Komulainen, P.; Penttilä, A.; Nystedt, J.; Korhonen, M. (2018)
    Background: Senescent cells are undesirable in cell therapy products due to reduced therapeutic activity and risk of aberrant cellular effects, and methods for assessing senescence are needed. Early-passage mesenchymal stromal cells (MSCs) are known to be small and spindle-shaped but become enlarged upon cell aging. Indeed, cell morphology is routinely evaluated during MSC production using subjective methods. We have therefore explored the possibility of utilizing automated imaging-based analysis of cell morphology in clinical cell manufacturing. Methods: An imaging system was adopted for analyzing changes in cell morphology of bone marrow-derived MSCs during long-term culture. Cells taken from the cultures at the desired passages were plated at low density for imaging, representing morphological changes observed in the clinical-grade cultures. The manifestations of aging and onset of senescence were monitored by population doubling numbers, expression of p16(INK4)a and p21(Cip1/Waf1), beta-galactosidase activity, and telomeric terminal restriction fragment analysis. Results: Cell area was the most statistically significant and practical parameter for describing morphological changes, correlating with biochemical senescence markers. MSCs from passages 1 (p1) and 3 (p3) were remarkably uniform in size, with cell areas between 1800 and 2500 mu m(2). At p5 the cells began to enlarge resulting in a 4.8-fold increase at p6-9 as compared to p1. The expression of p16(INK4a) and activity of beta-galactosidase had a strong correlation with the increase in cell area, whereas the expression of p21(Cip1/Waf1) reached its maximum at the onset of growth arrest and subsequently decreased. Mean telomere length shortened at an apparently constant rate during culture, from 8.2 +/- 0.3 kbp at p1, reaching 6.08 +/- 0.6 kbp at senescence. Conclusions: Imaging analysis of cell morphology is a useful tool for evaluating aging in cell cultures throughout the lifespan of MSCs. Our findings suggest that imaging analysis can reproducibly detect aging-related changes in cell morphology in MSC cultures. These findings suggest that cell morphology is still a supreme measure of cell quality and may be utilized to develop new noninvasive imaging-based methods to screen and quantitate aging in clinical-grade cell cultures.
  • Wickstrom, Jan-Erik; Jalkanen, Juho M.; Venermo, Maarit; Hakovirta, Harri H. (2017)
    Background and aims: Limited data exist on the association of the anatomical distribution of atherosclerotic lesions and the extent of atherosclerosis at defined arterial segments with life expectancy. We recently presented a new classification of the extent of atherosclerosis in crural vessels and showed that Crural Index (CIx) was associated with mid-term survival of symptomatic peripheral artery disease (PAD) patients. This study evaluates the significance of the extent of crural atherosclerosis on long-term cardiovascular mortality. Methods: 887 consecutive patients with PAD, admitted for digital subtraction angiography (DSA) at Turku University Hospital Department of Vascular Surgery (Turku, Finland) between January 1st, 2009 and July 30th, 2011, were retrospectively analysed. Each crural angiographic image was graded according to CIx criteria. Aorto-iliac and femoro-popliteal arterial segments were similarly graded according to modified TASC II criteria. CIx was used as the categorical variable for the extent of atherosclerosis in crural vessels for survival analysis. Survival was also evaluated with respect to which arterial segment was most severely affected. Causes of death were provided by the Cause of Death Registry of Statistics Finland, updated on January 23rd, 2017. Results: Altogether, 408 (46%) patients died during follow-up. The majority of deaths were due to cardiovascular causes (n = 246, 60%). Cardiovascular mortality was strongly associated with a high CIx (CIx III (Hazard ratio (HR) 2.16, Confidence interval (CI) 95% 1.23-3.80, p = 0.007)) and CIx IV (HR 3.513, 95% CI 1.93-4.565, p <0.001), as compared to CIx 0. In patients having the crural segment as the most severely affected arterial segment, cardiovascular mortality was significantly increased (HR 2.321, 95% CI 1.45-3.73, p <0.001), as was overall mortality (HR 2.177, 95% CI 1.53-3.10, p <0.001). Conclusions: High Crural Index and extensive crural vessel atherosclerosis are associated with long-term cardiovascular mortality, and both may serve as useful indicators of survival among patients with symptomatic PAD. (c) 2017 Elsevier B.V. All rights reserved.
  • Kaasalainen, Touko; Ekholm, Marja; Siiskonen, Teemu; Kortesniemi, Mika (2021)
    Cone beam computed tomography (CBCT) is a diverse 3D x-ray imaging technique that has gained significant popularity in dental radiology in the last two decades. CBCT overcomes the limitations of traditional twodimensional dental imaging and enables accurate depiction of multiplanar details of maxillofacial bony structures and surrounding soft tissues. In this review article, we provide an updated status on dental CBCT imaging and summarise the technical features of currently used CBCT scanner models, extending to recent developments in scanner technology, clinical aspects, and regulatory perspectives on dose optimisation, dosimetry, and diagnostic reference levels. We also consider the outlook of potential techniques along with issues that should be resolved in providing clinically more effective CBCT examinations that are optimised for the benefit of the patient.
  • Nieminen, H. J.; Ylitalo, T.; Karhula, S.; Suuronen, J. -P.; Kauppinen, S.; Serimaa, R.; Haeggstrom, E.; Pritzker, K. P. H.; Valkealahti, M.; Lehenkari, P.; Finnila, M.; Saarakkala, S. (2015)
    Objective: Collagen distribution within articular cartilage (AC) is typically evaluated from histological sections, e.g., using collagen staining and light microscopy (LM). Unfortunately, all techniques based on histological sections are time-consuming, destructive, and without extraordinary effort, limited to two dimensions. This study investigates whether phosphotungstic acid (PTA) and phosphomolybdic acid (PMA), two collagen-specific markers and X-ray absorbers, could (1) produce contrast for AC X-ray imaging or (2) be used to detect collagen distribution within AC. Method: We labeled equine AC samples with PTA or PMA and imaged them with micro-computed tomography (micro-CT) at pre-defined time points 0, 18, 36, 54, 72, 90, 180, 270 h during staining. The micro-CT image intensity was compared with collagen distributions obtained with a reference technique, i.e., Fourier-transform infrared imaging (FTIRI). The labeling time and contrast agent producing highest association (Pearson correlation, BlandeAltman analysis) between FTIRI collagen distribution and micro-CT -determined PTA distribution was selected for human AC. Results: Both, PTA and PMA labeling permitted visualization of AC features using micro-CT in non-calcified cartilage. After labeling the samples for 36 h in PTA, the spatial distribution of X-ray attenuation correlated highly with the collagen distribution determined by FTIRI in both equine (mean +/- S.D. of the Pearson correlation coefficients, r = 0.96 +/- 0.03, n = 12) and human AC (r = 0.82 +/- 0.15, n = 4). Conclusions: PTA-induced X-ray attenuation is a potential marker for non-destructive detection of AC collagen distributions in 3D. This approach opens new possibilities in development of non-destructive 3D histopathological techniques for characterization of OA. (C) 2015 The Authors. Published by Elsevier Ltd and Osteoarthritis Research Society International.
  • Di Saverio, Salomone; Podda, Mauro; De Simone, Belinda; Ceresoli, Marco; Augustin, Goran; Gori, Alice; Boermeester, Marja; Sartelli, Massimo; Coccolini, Federico; Tarasconi, Antonio; Angelis, Nicola de'; Weber, Dieter G.; Tolonen, Matti; Birindelli, Arianna; Biffl, Walter; Moore, Ernest E.; Kelly, Michael; Soreide, Kjetil; Kashuk, Jeffry; Ten Broek, Richard; Gomes, Carlos Augusto; Sugrue, Michael; Davies, Richard Justin; Damaskos, Dimitrios; Leppäniemi, Ari; Kirkpatrick, Andrew; Peitzman, Andrew B.; Fraga, Gustavo P.; Maier, Ronald V.; Coimbra, Raul; Chiarugi, Massimo; Sganga, Gabriele; Pisanu, Adolfo; Angelis, Gian Luigi de'; Tan, Edward; Van Goor, Harry; Pata, Francesco; Di Carlo, Isidoro; Chiara, Osvaldo; Litvin, Andrey; Campanile, Fabio C.; Sakakushev, Boris; Tomadze, Gia; Demetrashvili, Zaza; Latifi, Rifat; Abu-Zidan, Fakri; Romeo, Oreste; Segovia-Lohse, Helmut; Baiocchi, Gianluca; Costa, David; Rizoli, Sandro; Balogh, Zsolt J.; Bendinelli, Cino; Scalea, Thomas; Ivatury, Rao; Velmahos, George; Andersson, Roland; Kluger, Yoram; Ansaloni, Luca; Catena, Fausto (2020)
    Background and aims Acute appendicitis (AA) is among the most common causes of acute abdominal pain. Diagnosis of AA is still challenging and some controversies on its management are still present among different settings and practice patterns worldwide. In July 2015, the World Society of Emergency Surgery (WSES) organized in Jerusalem the first consensus conference on the diagnosis and treatment of AA in adult patients with the intention of producing evidence-based guidelines. An updated consensus conference took place in Nijemegen in June 2019 and the guidelines have now been updated in order to provide evidence-based statements and recommendations in keeping with varying clinical practice: use of clinical scores and imaging in diagnosing AA, indications and timing for surgery, use of non-operative management and antibiotics, laparoscopy and surgical techniques, intra-operative scoring, and peri-operative antibiotic therapy. Methods This executive manuscript summarizes the WSES guidelines for the diagnosis and treatment of AA. Literature search has been updated up to 2019 and statements and recommendations have been developed according to the GRADE methodology. The statements were voted, eventually modified, and finally approved by the participants to the consensus conference and by the board of co-authors, using a Delphi methodology for voting whenever there was controversy on a statement or a recommendation. Several tables highlighting the research topics and questions, search syntaxes, and the statements and the WSES evidence-based recommendations are provided. Finally, two different practical clinical algorithms are provided in the form of a flow chart for both adults and pediatric (<16 years old) patients. Conclusions The 2020 WSES guidelines on AA aim to provide updated evidence-based statements and recommendations on each of the following topics: (1) diagnosis, (2) non-operative management for uncomplicated AA, (3) timing of appendectomy and in-hospital delay, (4) surgical treatment, (5) intra-operative grading of AA, (6) ,management of perforated AA with phlegmon or abscess, and (7) peri-operative antibiotic therapy.
  • Di Saverio, Salomone; Podda, Mauro; De Simone, Belinda; Ceresoli, Marco; Augustin, Goran; Gori, Alice; Boermeester, Marja; Sartelli, Massimo; Coccolini, Federico; Tarasconi, Antonio; de’ Angelis, Nicola; Weber, Dieter G; Tolonen, Matti; Birindelli, Arianna; Biffl, Walter; Moore, Ernest E; Kelly, Michael; Soreide, Kjetil; Kashuk, Jeffry; Ten Broek, Richard; Gomes, Carlos A; Sugrue, Michael; Davies, Richard J; Damaskos, Dimitrios; Leppäniemi, Ari; Kirkpatrick, Andrew; Peitzman, Andrew B; Fraga, Gustavo P; Maier, Ronald V; Coimbra, Raul; Chiarugi, Massimo; Sganga, Gabriele; Pisanu, Adolfo; de’ Angelis, Gian L; Tan, Edward; Van Goor, Harry; Pata, Francesco; Di Carlo, Isidoro; Chiara, Osvaldo; Litvin, Andrey; Campanile, Fabio C; Sakakushev, Boris; Tomadze, Gia; Demetrashvili, Zaza; Latifi, Rifat; Abu-Zidan, Fakri; Romeo, Oreste; Segovia-Lohse, Helmut; Baiocchi, Gianluca; Costa, David; Rizoli, Sandro; Balogh, Zsolt J; Bendinelli, Cino; Scalea, Thomas; Ivatury, Rao; Velmahos, George; Andersson, Roland; Kluger, Yoram; Ansaloni, Luca; Catena, Fausto (BioMed Central, 2020)
    Abstract Background and aims Acute appendicitis (AA) is among the most common causes of acute abdominal pain. Diagnosis of AA is still challenging and some controversies on its management are still present among different settings and practice patterns worldwide. In July 2015, the World Society of Emergency Surgery (WSES) organized in Jerusalem the first consensus conference on the diagnosis and treatment of AA in adult patients with the intention of producing evidence-based guidelines. An updated consensus conference took place in Nijemegen in June 2019 and the guidelines have now been updated in order to provide evidence-based statements and recommendations in keeping with varying clinical practice: use of clinical scores and imaging in diagnosing AA, indications and timing for surgery, use of non-operative management and antibiotics, laparoscopy and surgical techniques, intra-operative scoring, and peri-operative antibiotic therapy. Methods This executive manuscript summarizes the WSES guidelines for the diagnosis and treatment of AA. Literature search has been updated up to 2019 and statements and recommendations have been developed according to the GRADE methodology. The statements were voted, eventually modified, and finally approved by the participants to the consensus conference and by the board of co-authors, using a Delphi methodology for voting whenever there was controversy on a statement or a recommendation. Several tables highlighting the research topics and questions, search syntaxes, and the statements and the WSES evidence-based recommendations are provided. Finally, two different practical clinical algorithms are provided in the form of a flow chart for both adults and pediatric (< 16 years old) patients. Conclusions The 2020 WSES guidelines on AA aim to provide updated evidence-based statements and recommendations on each of the following topics: (1) diagnosis, (2) non-operative management for uncomplicated AA, (3) timing of appendectomy and in-hospital delay, (4) surgical treatment, (5) intra-operative grading of AA, (6) ,management of perforated AA with phlegmon or abscess, and (7) peri-operative antibiotic therapy.
  • Suomalainen, Juha; Oliveira, Raquel A.; Hakala, Teemu; Koivumäki, Niko; Markelin, Lauri; Näsi, Roope; Honkavaara, Eija (Elsevier, 2021)
    Remote Sensing of Environment
    Multi- and hyperspectral cameras on drones can be valuable tools in environmental monitoring. A significant shortcoming complicating their usage in quantitative remote sensing applications is insufficient robust radiometric calibration methods. In a direct reflectance transformation method, the drone is equipped with a camera and an irradiance sensor, allowing transformation of image pixel values to reflectance factors without ground reference data. This method requires the sensors to be calibrated with higher accuracy than what is usually required by the empirical line method (ELM), but consequently it offers benefits in robustness, ease of operation, and ability to be used on Beyond-Visual Line of Sight flights. The objective of this study was to develop and assess a drone-based workflow for direct reflectance transformation and implement it on our hyperspectral remote sensing system. A novel atmospheric correction method is also introduced, using two reference panels, but, unlike in the ELM, the correction is not directly affected by changes in the illumination. The sensor system consists of a hyperspectral camera (Rikola HSI, by Senop) and an onboard irradiance spectrometer (FGI AIRS), which were both given thorough radiometric calibrations. In laboratory tests and in a flight experiment, the FGI AIRS tilt-corrected irradiances had accuracy better than 1.9% at solar zenith angles up to 70◦. The system’s lowaltitude reflectance factor accuracy was assessed in a flight experiment using reflectance reference panels, where the normalized root mean square errors (NRMSE) were less than ±2% for the light panels (25% and 50%) and less than ±4% for the dark panels (5% and 10%). In the high-altitude images, taken at 100–150 m altitude, the NRMSEs without atmospheric correction were within 1.4%–8.7% for VIS bands and 2.0%–18.5% for NIR bands. Significant atmospheric effects appeared already at 50 m flight altitude. The proposed atmospheric correction was found to be practical and it decreased the high-altitude NRMSEs to 1.3%–2.6% for VIS bands and to 2.3%– 5.3% for NIR bands. Overall, the workflow was found to be efficient and to provide similar accuracies as the ELM, but providing operational advantages in such challenging scenarios as in forest monitoring, large-scale autonomous mapping tasks, and real-time applications. Tests in varying illumination conditions showed that the reflectance factors of the gravel and vegetation targets varied up to 8% between sunny and cloudy conditions due to reflectance anisotropy effects, while the direct reflectance workflow had better accuracy. This suggests that the varying illumination conditions have to be further accounted for in drone-based in quantitative remote sensing applications.
  • Koledova, Zuzana; Howard, Beatrice A.; Englund, Johanna; Bach, Karsten; Bentires-Alj, Mohammed; Gonzalez-Suarez, Eva (2018)
    The European Network for Breast Development and Cancer (ENBDC), a worldwide network (http://www.enbdc.org/), celebrated its tenth anniversary with a fantastic meeting last March 15-17, 2018 in Weggis with 76 attendees.
  • Koledova, Zuzana; Howard, Beatrice A.; Englund, Johanna; Bach, Karsten; Bentires-Alj, Mohammed; Gonzalez-Suarez, Eva (BioMed Central, 2018)
    Abstract The European Network for Breast Development and Cancer (ENBDC), a worldwide network ( http://www.enbdc.org/ ), celebrated its tenth anniversary with a fantastic meeting last March 15–17, 2018 in Weggis with 76 attendees.
  • Sarparanta, Mirkka; Pourat, Jacob; Carnazza, Kathryn E.; Tang, Jun; Paknejad, Navid; Reiner, Thomas; Kostiainen, Mauri A.; Lewis, Jason S. (2020)
    Methods We have developed a nuclear and fluorescence labeling strategy for nanocrystalline cellulose (CNC), an emerging biomaterial with versatile chemistry and facile preparation from renewable sources. We modified CNC through 1,1′-carbonyldiimidazole (CDI) activation with radiometal chelators desferrioxamine B and 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), allowing for the labeling with zirconium-89 (t½ = 78.41 h) and copper-64 (t½ = 12.70 h), respectively, for non-invasive positron emission tomography (PET) imaging. The far-red fluorescent dye Cy5 was added for ex vivo optical imaging, microscopy and flow cytometry. The multimodal CNC were evaluated in the syngeneic orthotopic 4T1 tumor model of human stage IV breast cancer. Results Modified CNC exhibited low cytotoxicity in RAW 264.7 macrophages over 96 h, and high radiolabel stability in vitro. After systemic administration, radiolabeled CNC were rapidly sequestered to the organs of the reticulo-endothelial system (RES), indicating immune recognition and no passive tumor targeting by the enhanced permeability and retention (EPR) effect. Modification with NOTA was a more favorable strategy in terms of radiolabeling yield, specific radioactivity, and both the radiolabel and dispersion stability in physiological conditions. Flow cytometry analysis of Cy5-positive immune cells from the spleen and tumor corroborated the uptake of CNC to phagocytic cells. Conclusions Future studies on the in vivo behavior of CNC should be concentrated on improving the nanomaterial stability and circulation half-life under physiological conditions and optimizing further the labeling yields for the multimodality imaging strategy presented. Advances in knowledge Our studies constitute one of the first accounts of a multimodality nuclear and fluorescent probe for the evaluation of CNC biodistribution in vivo and outline the pitfalls in radiometal labeling strategies for future evaluation of targeted CNC-based drug delivery systems. Implications for patient care Quantitative and sensitive molecular imaging methods provide information on the structure–activity relationships of the nanomaterial and guide the translation from in vitro models to clinically relevant animal models.
  • Sammalkorpi, Henna E.; Leppäniemi, Ari; Lantto, Eila; Mentula, Panu (2017)
    Background: Diagnostic scoring is used to stratify patients with suspected appendicitis into three groups: high, intermediate, and low probability of appendicitis. The stratification can be used for selective imaging to avoid the harms of radiation without compromising diagnostic accuracy. The aim was to study how stratification by Adult Appendicitis Score affects diagnostic performance of imaging studies. Methods: Analysis of 822 patients who underwent diagnostic imaging for suspected appendicitis was made. Adult Appendicitis Score was used to stratify patients into groups of high, intermediate, and low probability of appendicitis. Diagnostic performance of computed tomography (CT) and ultrasound (US) was compared between these patient groups. Results: After scoring, pre-test probability of appendicitis ranged from 9-16% in low probability group to 75-79% in high probability group in patients who underwent US or CT. Post-test probability of appendicitis after positive CT was 99, 91, and 75% in high probability, intermediate probability and low probability groups, respectively, p <0.001. After positive US the respective probabilities were 95, 91 and 42%, p <0.001. Conclusion: Diagnostic imaging has limited value in patients with low probability of appendicitis according to Adult Appendicitis Score.
  • Le Joncour, Vadim; Laakkonen, Pirjo (2018)
    Accounting for 16 million new cases and 9 million deaths annually, cancer leaves a great number of patients helpless. It is a complex disease and still a major challenge for the scientific and medical communities. The efficacy of conventional chemotherapies is often poor and patients suffer from off-target effects. Each neoplasm exhibits molecular signatures - sometimes in a patient specific manner -that may completely differ from the organ of origin, may be expressed in markedly higher amounts and/ or in different location compared to the normal tissue. Although adding layers of complexity in the understanding of cancer biology, this cancer-specific signature provides an opportunity to develop targeting agents for early detection, diagnosis, and therapeutics. Chimeric antibodies, recombinant proteins or synthetic polypeptides have emerged as excellent candidates for specific homing to peripheral and central nervous system cancers. Specifically, peptide ligands benefit from their small size, easy and affordable production, high specificity, and remarkable flexibility regarding their sequence and conjugation possibilities. Coupled to imaging agents, chemotherapies and/or nanocarriers they have shown to increase the on-site delivery, thus allowing better tumor mass contouring in imaging and increased efficacy of the chemotherapies associated with reduced adverse effects. Therefore, some of the peptides alone or in combination have been tested in clinical trials to treat patients. Peptides have been well-tolerated and shown absence of toxicity. This review aims to offer a view on tumor targeting peptides that are either derived from natural peptide ligands or identified using phage display screening. We also include examples of peptides targeting the high-grade malignant tumors of the central nervous system as an example of the complex therapeutic management due to the tumor's location. Peptide vaccines are outside of the scope of this review. (C) 2017 The Authors. Published by Elsevier Ltd.
  • Jalkanen, Juho M.; Wickstrom, Jan-Erik; Venermo, Maarit; Hakovirta, Harri H. (2016)
    Background and aims: Several studies report correlation of ankle brachial index (ABI) values and mortality. However, no studies exist on the predictive value of anatomical distribution of atherosclerotic lesions and the extent of atherosclerosis at defined arterial segments on life expectancy. The aim of the present study was to evaluate the significance of both extent and localisation of atherosclerotic lesions to mid-term patient survival. Methods: Digital subtraction angiography (DSA) images of 887 consecutive patients admitted to the Department of Vascular Surgery at Turku University Hospital (Turku, Finland) were retrospectively analysed. Each angiography was classified according to the TASC II classification for aorto-iliac and femoro-popliteal segments, and a similar four-grade index was created for crural arteries. Patients were followed until 36-months post DSA. Results: During 36-month follow-up 295 (33%) deaths occurred. Death during follow-up was strongly associated with extensive crural disease, but not with extensive proximal disease (Crural Index p = 0.044 and <0.001, respectively). In a Cox regression analysis incorporating baseline variables, Crural Index IV and most severe atherosclerosis on crural vessels were the strongest predictors of poor prognosis (HR 2.20 95% CI 1.3-3.7, p = 0.003 and HR 2.45 95% CI 1.5-4.0, p <0.001 respectively). Conclusions: The extent of crural atherosclerosis is independently associated with poor mid term life expectancy. Therefore, a classification of the extent of crural atherosclerosis could serve as an indicator of mortality among PAD patients and aid in clinical decision making. (C) 2016 Elsevier Ireland Ltd. All rights reserved.