920 resultados para differentiate


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Matrix metalloproteinases (MMPs) represent a family of 23 metalloendopeptidases, collectively capable of degrading all components of the extracellular matrix. MMPs have been implicated in several inflammatory processes such as arthritis, atherosclerosis, and even carcinomas. They are also involved in several beneficial activities such as epithelial repair. MMPs are inhibited by endogenous tissue inhibitors of matrix metalloproteinases (TIMP). In this study, MMPs were investigated in intestinal mucosa of inflammatory bowel diseases (IBD), chronic intestinal disorders. The main focus was to characterize mucosal inflammation in the intestine, but also cutaneous pyoderma gangrenosum (PG), to assess similarites with IBD inflammation. MMPs and TIMPs were mainly examined in colonic mucosa, in adult Crohn s disease (CD), and paediatric CD, ulcerative colitis (UC), and indeterminate colitis (IC). Ileal pouch mucosa of proctocolectomized paediatric onset IBD patients was also investigated to characterize pouch mucosa. The focus was on finding specific MMPs that could act as markers to differentiate between different IBD disorders, and MMPs that could be implied as markers for tissue injury, potentially serving as targets for MMP-inhibitors. All examinations were performed using immunohistochemistry. The results show that immunosuppressive agents decrease stromal expression of MMP-9 and -26 that could serve as specific targets for MMP-inhibitors in treating CD. In paediatric colonic inflammation, MMP-10 and TIMP-3 present as molecular markers for IBD inflammation, and MMP-7 for CD. MMP expression in the the pouch mucosa could not be classified as strictly IBD- or non-IBD-like. For the first time, this study describes the expression of MMP-3, -7, -9, -12, and TIMP-2 and -3 in pouch mucosa. The MMP profile in PG bears resemblance to both intestinal IBD inflammation and cutaneous inflammation. Based on the results, MMPs and their inhibitors emerge as promising tools in the differential diagnosis of IBD and characterization of the disease subtype, although further research is necessary. Furthermore, the expression of several MMPs in pouch has been described for the first time. While further research is warranted, the findings contribute to a better understanding of events occurring in IBD mucosa, as well as pyoderma gangrenosum.

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Prostate cancer (PCa) is the most commonly diagnosed non-skin cancer and second leading cause of cancer-related death of men in developed countries. Measurement of prostate specific antigen (PSA) is a very sensitive method for diagnosing and monitoring of prostate cancer (PCa), but the specificity needs improvement. Measurements of different molecular forms of PSA have been shown to improve differentiation between PCa and benign prostatic diseases. However, accurate measurement of some isoforms has not been achieved in previous assays. The aim of the present study was to develop new assays that reliably measure enzymatically active PSA, PSA-α1-chymotryposin (PSA-ACT) and PSA-α1-protease inhibitor (PSA-API), and to evaluate their diagnostic value. Double-label immunofluorometric assays using a novel monoclonal antibody (MAb) and another antibody to either free PSA (fPSA) or total PSA (tPSA) were developed and used to measure PSA-ACT and fPSA or tPSA at the same time. These assays provide enough sensitivity for measurement of PSA-ACT in sera with low PSA levels. The results obtained confirmed that proportion of PSA-ACT to tPSA (%PSA-ACT) was as useful as proportion of fPSA to tPSA (%fPSA) for discrimination between PCa and benign prostatic hyperplasia (BPH). We developed an immunoassay for detection of PSA-API based on proximity ligation, which improved assay sensitivity 10-fold compared with conventional assays. Our results confirmed previous findings that the PSA-API level is somewhat lower in men with than without PCa, and the combination of %fPSA and proportion of PSA-API to tPSA (%PSA-API) provides diagnostic improvement compared with either method alone. Assays based on this principle should be applicable to other immunoassays in which the nonspecific background is a problem. An immunopeptidometric sandwich assay (IPMA) was developed to measure the enzymatically active PSA. This assay showed high specificity, but sensitivity was not good enough for measurement of PSA concentrations in the gray zone, 2-10 µg/L, in which tPSA does not efficiently differentiate between PCa and BPH. We further developed a solid-phase proximity ligation immunoassay, which provided a 10-fold improvement in sensitivity. This proof of concept study shows that peptides reacting with proteins are potentially useful for sensitive and specific measurement of protein variants for which specific MAbs cannot be obtained.

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The incidence of non-melanoma skin cancer is increasing worldwide. Basal cell carcinoma followed by squamous cell carcinoma and malignant melanoma are the most frequent skin tumors. Immunosuppressed patients have an increased risk of neoplasia, of which non-melanoma skin cancer is the most common. Matrix metalloproteinases (MMPs) are proteolytic enzymes that collectively are capable of degrading virtually all components of the extracellular matrix. MMPs can also process substrates distinct from extracellular matrix proteins and influence cell proliferation, differentiation, angiogenesis, and apoptosis. MMP activity is regulated by their natural inhibitors, tissue inhibitors of metallopro-teinases (TIMPs). In this study, the expression patterns of MMPs, TIMPs, and certain cancer-related molecules were investigated in premalignant and malignant lesions of the human skin. As methods were used immunohistochemisty, in situ hybridization, and reverse transcriptase polymerase chain reaction (RT-PCR) from the cell cultures. Our aim was to evaluate the expression pattern of MMPs in extramammary Paget's disease in order to find markers for more advanced tumors, as well as to shed light on the origin of this rare neoplasm. Novel MMPs -21, -26, and -28 were studied in melanoma cell culture, in primary cutaneous melanomas, and their sentinel nodes. The MMP expression profile in keratoacanthomas and well-differentiated squamous cell carcinomas was analyzed to find markers to differentiate benign keratinocyte hyperproliferation from malignantly transformed cells. Squamous cell carcinomas of immunosuppressed organ transplant recipients were compared to squamous cell carcinomas of matched immunocompetent controls to investigate the factors explaining their more aggressive nature. We found that MMP-7 and -19 proteins are abundant in extramammary Paget's disease and that their presence may predict an underlying adenocarcinoma in these patients. In melanomas, MMP-21 was upregulated in early phases of melanoma progression, but disappeared from the more aggressive tumors with lymph node metastases. The presence of MMP-13 in primary melanomas and lymph node metastases may relate to more aggressive disease. In keratoacanthomas, the expression of MMP-7 and -9 is rare and therefore should raise a suspicion of well-differentiated squamous cell carcinomas. Furthermore, MMP-19 and p16 were observed in benign keratinocyte hyperproliferation of keratoacanthomas, whereas they were generally lost from malignant keratinocytes of SCCs. MMP-26 staining was significantly stronger in squamous cell carcinomas and Bowen s disease samples of organ transplant recipients and it may contribute to the more aggressive nature of squamous cell carcinomas in immunosuppressed patients. In addition, the staining for MMP-9 was significantly stronger in macrophages surrounding the tumors of the immunocompetent group and in neutrophils of those patients on cyclosporin medication. In conclusion, based on our studies, MMP-7 and -19 might serve as biomarkers for more aggressive extramammary Paget's disease and MMP-21 for malignant transformation of melanocytes. MMP -7, -9, and -26, however, could play an important role in the pathobiology of keratinocyte derived malignancies.

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The adequacy of anesthesia has been studied since the introduction of balanced general anesthesia. Commercial monitors based on electroencephalographic (EEG) signal analysis have been available for monitoring the hypnotic component of anesthesia from the beginning of the 1990s. Monitors measuring the depth of anesthesia assess the cortical function of the brain, and have gained acceptance during surgical anesthesia with most of the anesthetic agents used. However, due to frequent artifacts, they are considered unsuitable for monitoring consciousness in intensive care patients. The assessment of analgesia is one of the cornerstones of general anesthesia. Prolonged surgical stress may lead to increased morbidity and delayed postoperative recovery. However, no validated monitoring method is currently available for evaluating analgesia during general anesthesia. Awareness during anesthesia is caused by an inadequate level of hypnosis. This rare but severe complication of general anesthesia may lead to marked emotional stress and possibly posttraumatic stress disorder. In the present series of studies, the incidence of awareness and recall during outpatient anesthesia was evaluated and compared with that of in inpatient anesthesia. A total of 1500 outpatients and 2343 inpatients underwent a structured interview. Clear intraoperative recollections were rare the incidence being 0.07% in outpatients and 0.13% in inpatients. No significant differences emerged between outpatients and inpatients. However, significantly smaller doses of sevoflurane were administered to outpatients with awareness than those without recollections (p<0.05). EEG artifacts in 16 brain-dead organ donors were evaluated during organ harvest surgery in a prospective, open, nonselective study. The source of the frontotemporal biosignals in brain-dead subjects was studied, and the resistance of bispectral index (BIS) and Entropy to the signal artifacts was compared. The hypothesis was that in brain-dead subjects, most of the biosignals recorded from the forehead would consist of artifacts. The original EEG was recorded and State Entropy (SE), Response Entropy (RE), and BIS were calculated and monitored during solid organ harvest. SE differed from zero (inactive EEG) in 28%, RE in 29%, and BIS in 68% of the total recording time (p<0.0001 for all). The median values during the operation were SE 0.0, RE 0.0, and BIS 3.0. In four of the 16 organ donors, EEG was not inactive, and unphysiologically distributed, nonreactive rhythmic theta activity was present in the original EEG signal. After the results from subjects with persistent residual EEG activity were excluded, SE, RE, and BIS differed from zero in 17%, 18%, and 62% of the recorded time, respectively (p<0.0001 for all). Due to various artifacts, the highest readings in all indices were recorded without neuromuscular blockade. The main sources of artifacts were electrocauterization, electromyography (EMG), 50-Hz artifact, handling of the donor, ballistocardiography, and electrocardiography. In a prospective, randomized study of 26 patients, the ability of Surgical Stress Index (SSI) to differentiate patients with two clinically different analgesic levels during shoulder surgery was evaluated. SSI values were lower in patients with an interscalene brachial plexus block than in patients without an additional plexus block. In all patients, anesthesia was maintained with desflurane, the concentration of which was targeted to maintain SE at 50. Increased blood pressure or heart rate (HR), movement, and coughing were considered signs of intraoperative nociception and treated with alfentanil. Photoplethysmographic waveforms were collected from the contralateral arm to the operated side, and SSI was calculated offline. Two minutes after skin incision, SSI was not increased in the brachial plexus block group and was lower (38 ± 13) than in the control group (58 ± 13, p<0.005). Among the controls, one minute prior to alfentanil administration, SSI value was higher than during periods of adequate antinociception, 59 ± 11 vs. 39 ± 12 (p<0.01). The total cumulative need for alfentanil was higher in controls (2.7 ± 1.2 mg) than in the brachial plexus block group (1.6 ± 0.5 mg, p=0.008). Tetanic stimulation to the ulnar region of the hand increased SSI significantly only among patients with a brachial plexus block not covering the site of stimulation. Prognostic value of EEG-derived indices was evaluated and compared with Transcranial Doppler Ultrasonography (TCD), serum neuron-specific enolase (NSE) and S-100B after cardiac arrest. Thirty patients resuscitated from out-of-hospital arrest and treated with induced mild hypothermia for 24 h were included. Original EEG signal was recorded, and burst suppression ratio (BSR), RE, SE, and wavelet subband entropy (WSE) were calculated. Neurological outcome during the six-month period after arrest was assessed with the Glasgow-Pittsburgh Cerebral Performance Categories (CPC). Twenty patients had a CPC of 1-2, one patient had a CPC of 3, and nine patients died (CPC 5). BSR, RE, and SE differed between good (CPC 1-2) and poor (CPC 3-5) outcome groups (p=0.011, p=0.011, p=0.008, respectively) during the first 24 h after arrest. WSE was borderline higher in the good outcome group between 24 and 48 h after arrest (p=0.050). All patients with status epilepticus died, and their WSE values were lower (p=0.022). S-100B was lower in the good outcome group upon arrival at the intensive care unit (p=0.010). After hypothermia treatment, NSE and S-100B values were lower (p=0.002 for both) in the good outcome group. The pulsatile index was also lower in the good outcome group (p=0.004). In conclusion, the incidence of awareness in outpatient anesthesia did not differ from that in inpatient anesthesia. Outpatients are not at increased risk for intraoperative awareness relative to inpatients undergoing general anesthesia. SE, RE, and BIS showed non-zero values that normally indicate cortical neuronal function, but were in these subjects mostly due to artifacts after clinical brain death diagnosis. Entropy was more resistant to artifacts than BIS. During general anesthesia and surgery, SSI values were lower in patients with interscalene brachial plexus block covering the sites of nociceptive stimuli. In detecting nociceptive stimuli, SSI performed better than HR, blood pressure, or RE. BSR, RE, and SE differed between the good and poor neurological outcome groups during the first 24 h after cardiac arrest, and they may be an aid in differentiating patients with good neurological outcomes from those with poor outcomes after out-of-hospital cardiac arrest.

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The existing clinical biomarkers for prostate cancer (PCa) are not ideal, since they cannot specifically differentiate between those patients who should be treated immediately and those who should avoid overtreatment. Current screening techniques lack specificity, and a decisive diagnosis of PCa is based on prostate biopsy. Although PCa screening is widely utilized nowadays, two-thirds of the biopsies performed are still unnecessary. Thus, the discovery of noninvasive PCa biomarkers remains an urgent unmet medical need. Once metastasized, there is still no curative therapy. A better understanding of sustained androgen receptor signalling in castration resistant prostate cancer (CRPC) has now led to the development of more effective therapies. We need a better understanding of the molecular and cellular aspects of prostate carcinogenesis and progression. Identification of cancer initiating cells and therapies against these populations is a promising way forward to fight this disease.

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Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive disorder in which the cardinal symptoms arise from exocrine pancreatic insufficiency and bone marrow dysfunction. Previous studies have suggested increased risk of fatal complications among Finnish SDS infants. The genetic defect responsible for the disease was recently identified; the SBDS gene is located at chromosome 7q11 and encodes a protein that is involved in ribosome biosynthesis. The discovery of the SBDS gene has opened new insights into the pathogenesis of this multi-organ disease. This study aimed to assess phenotypic and genotypic features of Finnish patients with SDS. Seventeen Finnish patients with a clinical diagnosis of SDS were included in the study cohort. Extensive clinical, biochemical and imaging assessments were performed to elucidate the phenotypic features, and the findings were correlated with the SBDS genotype. Imaging studies included abdominal magnetic reso-nance imaging (MRI), brain MRI, cardiac echocardiography including tissue Doppler examination, and cardiac MRI. The skeletal phenotype was assessed by dual-energy X-ray absorptiometry and bone histomorphometry. Twelve patients had mutations in the SBDS gene. In MRI, a characteristic pattern of fat-replaced pancreas with occasional enhancement of scattered parenchymal foci and of pancreatic duct was noted in the SBDS mutation-positive patients while the mutation-negative patients did not have pancreatic fat accumulation. The patients with SBDS mutations had significantly reduced bone mineral density associated with low-energy peripheral fractures and vertebral compression fractures. Bone histomorphometry confirmed low-turnover osteoporosis. The patients with SBDS mutations had learning difficulties and smaller head size and brain volume than control subjects. Corpus callosum, cerebellar vermis, and pos-terior fossa structures were significantly smaller in SDS patients than in controls. Patients with SDS did not have evidence of clinical heart disease or myocardial fibrosis. However, subtle diastolic changes in the right ventricle and exercise-induced changes in the left ventricle contractile reserve were observed. This study expanded the phenotypic features of SDS to include primary low-turnover osteoporosis and structural alterations in the brain. Pancreatic MRI showed characteristic changes in the SBDS mutation-positive patients while these were absent in the mutation-negative patients, suggesting that MRI can be used to differentiate patients harbouring SBDS mutations from those without mutations. No evidence for clinical cardiac manifestations was found, but imaging studies revealed slightly altered myocardial function that may have clinical implications. These findings confirm the pleiotropic nature of SDS and underscore the importance of careful multidisciplinary follow-up of the affected individuals.

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Breast cancer is the most common malignancy in women in Western countries. It is a heterogeneous disease with varying biological characteristics and aggressiveness. Family history is one of the strongest predisposing factors for breast cancer. The known susceptibility genes explain only around 25% of all familial breast cancers. At least part of the unknown familial aggregation may be caused by several low-penetrance variants that occur commonly in the general population. Cyclins are cell cycle-regulating proteins. Cyclin expression oscillates during the cell cycle and is under strict control. In cancer cells, cyclin expression often becomes deregulated, leading to uncontrolled cell division and proliferation, one of the hallmarks of cancer. In this study, we investigated the role of cyclins in breast cancer predisposition, pathogenesis, and tumor behavior. Cyclin A immunohistochemistry was evaluated both on traditional large sections and on tissue microarrays (TMA). The concordance of the results was good, indicating that TMA is a reliable method for studying cyclin expression in breast cancer. The expression of cyclins D1, E, and B1 was studied among 1348 invasive breast cancers on TMA. Familial BRCA1/2-mutation negative tumors had significantly more often low cyclin E and high cyclin D1 expression than BRCA1/2 related or sporadic tumors. Unique cyclin E and D1 expression patterns among familial non-BRCA1/2 breast cancers may reflect different predisposition and pathogenesis in these groups and help to differentiate mutation-positive from mutation-negative familial cancers. High cyclin E expression was associated with an aggressive breast cancer phenotype and was an independent marker of poor metastasis-free survival. High cyclin D1 was associated with high grade and high proliferation among estrogen receptor (ER)-positive but with low grade and low proliferation among ER-negative breast cancers. Among ER-positive cancers not treated with chemotherapy, high cyclin D1 showed a trend towards shorter metastasis-free survival. These results suggest that different mechanisms may drive proliferation in ER-negative and -positive breast cancers and that cyclin D1 has a particularly important role in tumorigenesis of hormone receptor-positive breast cancer. High cyclin B1 expression was associated with aggressive breast cancer features and had an independent impact on survival. The results suggest that cyclin B1 immunohistochemistry is a method that could easily be adapted for routine use and is an independent prognostic factor, adding specificity to prognostic evaluation conducted with traditional markers. A commonly occurring cyclin D1 gene polymorphism A870G was associated with increased breast cancer risk in a large material of Finnish and Canadian breast cancer patients. The interaction of the high-activity alleles of cyclin D1 gene and estrogen metabolism gene COMT conferred an even higher risk. These results show that cyclin D1 and COMT act synergistically to contribute to breast cancer progression and that individual risk for breast cancer can be altered by the combined effect of polymorphisms with low-penetrance alleles. By investigating critical cell cycle regulator protein cyclins, we revealed new aspects of breast cancer predisposition, pathogenesis, and clinical course.

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Purpose: The aim of the present study was to develop and test new digital imaging equipment and methods for diagnosis and follow-up of ocular diseases. Methods: The whole material comprised 398 subjects (469 examined eyes), including 241 patients with melanocytic choroidal tumours, 56 patients with melanocytic iris tumours, 42 patients with diabetes, a 52-year old patient with chronic phase of VKH disease, a 30-year old patient with an old blunt eye injury, and 57 normal healthy subjects. Digital 50° (Topcon TRC 50 IA) and 45° (Canon CR6-45NM) fundus cameras, a new handheld digital colour videocamera for eye examinations (MediTell), a new subtraction method using the Topcon Image Net Program (Topcon corporation, Tokyo, Japan), a new method for digital IRT imaging of the iris we developed, and Zeiss photoslitlamp with a digital camera body were used for digital imaging. Results: Digital 50° red-free imaging had a sensitivity of 97.7% and two-field 45° and 50° colour imaging a sensitivity of 88.9-94%. The specificity of the digital 45°-50° imaging modalities was 98.9-100% versus the reference standard and ungradeable images that were 1.2-1.6%. By using the handheld digital colour video camera only, the optic disc and central fundus located inside 20° from the fovea could be recorded with a sensitivity of 6.9% for detection of at least mild NPDR when compared with the reference standard. Comparative use of digital colour, red-free, and red light imaging showed 85.7% sensitivity, 99% specificity, and 98.2 % exact agreement versus the reference standard in differentiation of small choroidal melanoma from pseudomelanoma. The new subtraction method showed growth in four of 94 melanocytic tumours (4.3%) during a mean ±SD follow-up of 23 ± 11 months. The new digital IRT imaging of the iris showed the sphincter muscle and radial contraction folds of Schwalbe in the pupillary zone and radial structural folds of Schwalbe and circular contraction furrows in the ciliary zone of the iris. The 52-year-old patient with a chronic phase of VKH disease showed extensive atrophy and occasional pigment clumps in the iris stroma, detachment of the ciliary body with severe ocular hypotony, and shallow retinal detachment of the posterior pole in both eyes. Infrared transillumination imaging and fluorescein angiographic findings of the iris showed that IR translucence (p=0.53), complete masking of fluorescence (p=0.69), presence of disorganized vessels (p=0.32), and fluorescein leakage (p=1.0) at the site of the lesion did not differentiate an iris nevus from a melanoma. Conclusions: Digital 50° red-free and two-field 50° or 45° colour imaging were suitable for DR screening, whereas the handheld digital video camera did not fulfill the needs of DR screening. Comparative use of digital colour, red-free and red light imaging was a suitable method in the differentiation of small choroidal melanoma from different pseudomelanomas. The subtraction method may reveal early growth of the melanocytic choroidal tumours. Digital IRT imaging may be used to study changes of the stroma and posterior surface of the iris in various diseases of the uvea. It contributed to the revealment of iris atrophy and serous detachment of the ciliary body with ocular hypotony together with the shallow retinal detachment of the posterior pole as new findings of the chronic phase of VKH disease. Infrared translucence and angiographic findings are useful in differential diagnosis of melanocytic iris tumours, but they cannot be used to determine if the lesion is benign or malignant.

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Background Interest in the use of healing gardens in healthcare settings to provide therapeutic benefits is increasing, however insight is needed to determine whether patients, patient families and friends, and staff who spend time in these gardens use these in the manner for which they were designed, and experience the benefits suggested by broader research in this field. Objective(s) Visitors to four of the LCCH gardens have left comments in ‘bench diaries’ (visitors books). Analysis of these comments yields valuable insights into the use of the gardens, enabling reflection on the design intent and outcomes and guidance regarding how the gardens might be better utilised, as well as a basis for further investigation into the use and value of the gardens. Method(s) Comments have been coded and analysed using a thematic analysis approach to identify patterns relating to the reasons for which people appear to come to the healing gardens; benefits they appear to receive from spending time there; and features and aspects of the gardens that they appear to appreciate in particular. Only comments related to the gardens have been used in this analysis, with all comments being deidentified. Outcome/Conclusion Comments left in the Adventure Garden and Secret Garden bench diaries were used for the analysis, as Staff Garden and Babies Garden bench diary comments did not relate to the garden. There were no negative comments relating to the gardens, other than one comment requesting additional benches. The vast majority of comments expressed gratitude for the space. The four most frequently observed themes from the comments left in the Secret Garden Bench Diary indicated that they were seeking ‘time out’ from their experiences of being at the hospital, a desire for a ‘dose of nature’ (greenery, beautiful garden, etc), and fresh air, and that the garden space provided a restorative experience to them in some manner. Comments in the Adventure Garden Bench Diary related predominately to the view. Analysis of the comments emphasises the importance of gardens providing multi-sensory experiences that significantly differentiate the space from the hospital ward and provide visitors with a sense of being away, of peacefulness, and of familiarity with the outside world. Positioning gardens with prospect, and solar aspect, appears important in these regards, as does the presence of visible greenery. Adequate seating in locations that provide pleasing views appears particularly important for staff and adult visitors. Whilst comments in the Bench Diaries did not indicate direct awareness of the stress and anxiety-reducing effects that research elsewhere has found from viewing plants and nature, however these effects may underpin many of these experiences that visitors did share.

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Although hundreds of thousands of organic products are traded on a daily basis, it is less known how imported organic products are evaluated by consumers in an importing country. The paper analyzes Japanese wine point of sale (POS) data to examine whether consumers differentiate between local and imported organic products. The results of our hedonic analyses show that the premium for imported organic red (white) wines is about 42.996 % (8.872 %) while that for domestic red (white) organic wines is about 6.440 % (1.214 %), implying that Japanese consumers pay higher premiums for imported organic agricultural products than for those produced in Japan.

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The aim of this study was to identify and describe the types of errors in clinical reasoning that contribute to poor diagnostic performance at different levels of medical training and experience. Three cohorts of subjects, second- and fourth- (final) year medical students and a group of general practitioners, completed a set of clinical reasoning problems. The responses of those whose scores fell below the 25th centile were analysed to establish the stage of the clinical reasoning process - identification of relevant information, interpretation or hypothesis generation - at which most errors occurred and whether this was dependent on problem difficulty and level of medical experience. Results indicate that hypothesis errors decrease as expertise increases but that identification and interpretation errors increase. This may be due to inappropriate use of pattern recognition or to failure of the knowledge base. Furthermore, although hypothesis errors increased in line with problem difficulty, identification and interpretation errors decreased. A possible explanation is that as problem difficulty increases, subjects at all levels of expertise are less able to differentiate between relevant and irrelevant clinical features and so give equal consideration to all information contained within a case. It is concluded that the development of clinical reasoning in medical students throughout the course of their pre-clinical and clinical education may be enhanced by both an analysis of the clinical reasoning process and a specific focus on each of the stages at which errors commonly occur.

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In the absence of specific treatable mutations, platinum-based chemotherapy remains the gold standard of treatment for lung cancer patients. However, 5-year survival rates remain poor due to the development of resistance and eventual relapse. Resistance to conventional cytotoxic therapies presents a significant clinical challenge in the treatment of this disease. The cancer stem cell (CSC) hypothesis suggests that tumors are arranged in a hierarchical structure, with the presence of a small subset of stem-like cells that are responsible for tumor initiation and growth. This CSC population has a number of key properties such as the ability to asymmetrically divide, differentiate and self-renew, in addition to having increased intrinsic resistance to therapy. While cytotoxic chemotherapy kills the bulk of tumor cells, CSCs are spared and have the ability to recapitulate the heterogenic tumor mass. The identification of lung CSCs and their role in tumor biology and treatment resistance may lead to innovative targeted therapies that may ultimately improve clinical outcomes in lung cancer patients. This review will focus on lung CSC markers, their role in resistance and their relevance as targets for future therapies.

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In this research I ask what is interpreted as sex-based harassment by 15-16-year old girls and boys. By sex-based harassment I refer to one-sided, unwanted attention that is based on gender and that makes the target feel embarrassed, frightened, hurt or angry. My focus is not on the most overt cases of harassment but rather on everyday encounters. While young people differentiate between harassing and non-harassing attention, at the same time they define, assign value to and construct differences and power relations on the basis of gender, age and ethnicity, for example. My main data consists of essays (N 104, 54 girls, 54 boys) and thematic interviews (N 14; 20 girls, 3 boys) of ninth graders of a secondary school in Helsinki. In the essays and interviews, students construe the border between pleasant and unpleasant, tolerable and intolerable attention as clear in principle, but, they suggest that in practice this border is ambivalent, negotiable and contextual. The interpretations of incidents are justified by referring to features of the target, the scene or the perpetrator. Targets of harassment are most often construed as being girls who are characterized as thin-skinned, but at the same time they are expected to be understanding toward any sex-based attention they may get, particularly when it is not physical. On the other hand, girls are regarded as equal and even active participants in incidents of harassment. Such statements include considerations of how girls either reject or invite particular kinds of attention by their actions and outward appearance. Forms of harassment, ways of understanding it as well as overcoming it vary according to spatial context. By situating incidents in different spaces and places, young people contrast their experiences with ordinary and predictable non-harassment that takes place e.g. in discos and unusual and unexpected harassment that takes place e.g. in the city streets in the daytime. The behaviour of boys harassing a girls is naturalized by appealing to young masculinity and the childishness but also strong sexual drive which is seen as characteristic of teenage boys. On the other hand, sex-based harassment is racialized and pathologized in ways that separate the phenomenon from young, Finnish, normal masculinity. Both the material experiences of the young people and the definitions of the parties involved in harassing incidents are gendered. Girls encounter and deal with sexualized commenting and unwanted approaches much more often and in a more intensive way than boys. Furthermore, there is a vast cultural repertoire of acceptable accounts that can be mobilised in order to excuse male harassers, to critically evaluate the appearance or action of the female targets and to divide the responsibility between the female target and the male perpetrator.

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The thesis The portrait interview as a newspaper genre. A qualitative close reading focussing on topical motifs, conventions of narration, and gender defines the portrait interview as a newspaper genre and analyses how the personalities in the portraits are constructed textually. The main body of material consists of 107 portrait interviews in two morning newspapers, Dagens Nyheter (published in Stockholm, Sweden) and Hufvudstadsbladet (published in Swedish in Helsinki, Finland), during two one-week periods (week 46/1999 and week 38/2002). There is also complementary material of 59 portraits from four magazines. The study is carried out within the research traditions of journalistic genre studies, gender and journalism, and critical text analysis. It is comprised of a qualitative close reading focussing on content (topical motifs or themes), conventions of narration, and gender. The methods used to carry out the study are qualitative close reading and quantitative content analysis. The analysis identifies the stylistic elements that differentiate the portrait genre from other journalistic genres, as well as from the autobiographical genre, and explores what opportunities and limitations these elements present for the inclusion of even more women protagonists in the portrait genre. The portrait interview is an exception from the critical mission of journalism in general, with its position as a genre of politeness. Since a typical characteristic of the portrait interview genre is that it pays tribute to the protagonist, the genre reveals the kind of personalities and lives that are seen as admirable in society. Four levels of portrait interview are defined: the prototype portrait, the pure portrait, the hybrid portrait and the marginal portrait. The prototype is a raw version of a portrait that fulfils the criteria but may be lacking in content and stylistics. The pure portrait does not lack these qualities and resembles an ideal portrait. The hybrid is a borderline case which relates to another genre or is a mixture between the portrait and some other genre, most commonly the news genre. The marginal portrait does not fulfil the criteria, and can therefore be seen as an inadequate portrait. For example, obituaries and caricatures are excluded if the protagonist s voice is never quoted. The analysis resulted in three factors that in part help to explain why the portrait interview genre has somewhat more female protagonists than journalistic news texts do in general. The four main reasons why women are presented somewhat more in the portrait genre than in other journalistic genres are: (i) women are shown as exceptions to the female norm when, for example, taking a typical male job or managing in positions where there are few women; (ii) women are shown as representing female themes ; (iii) use of the double bind as a story-generating factor; and (iv) the intimisation of journalism. The double bind usually builds up the narration on female ambiguity in the contradiction between private and public life, for example family and career, personal desire and work. The intimisation of journalism and the double bind give women protagonists somewhat more publicity also because of the tendency of portrait interviews to create conflicts within the protagonist, as an exception to journalism in general where conflicts are created or seen as existing between, for example, persons, groupings or parties. Women protagonists and their lives create an optimal narration of inner conflicts originating in the double bind as men are usually not seen as suffering from these conflicts. The analysis also resulted in gendered portrait norms: The feminine portrait norm and the masculine portrait norm or more concretely, professional life and family life as expectation and exception. Women are expected to be responsible parents and mediocre professionals, while men are expected to be professionals and in their free time engaging fathers. Key words: journalism, genre, portrait interview, gender, interview, newspaper, women s magazine.

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This thesis studies the tree species’ juvenile diversity in cacao (Theobroma cacao L.) based agroforestry and in primary forest in a natural conservation forest environment of Lore Lindu National Park, Sulawesi, Indonesia. Species’ adult composition in Lore Lindu National Park is relatively well studied, less is known about tree species’ diversity in seedling communities particularly in frequently disturbed cacao agroforestry field environment. Cacao production forms a potentially serious thread for maintaining the conservation areas pristine and forested in Sulawesi. The impacts of cacao production on natural environment are directly linked to the diversity and abundance of shade tree usage. The study aims at comparing differences between cacao agroforestry and natural forest in the surrounding area in their species composition in seedling and sapling size categories. The study was carried out in two parts. Biodiversity inventory of seedlings and saplings was combined with social survey with farmer interviews. Aim of the survey was to gain knowledge of the cacao fields, and farmers’ observations and choices regarding tree species associated with cacao. Data was collected in summer 2008. The assessment of the impact of environmental factors of solar radiation, weeding frequency, cacao tree planting density, distance to forest and distance to main park road, and type of habitat on seedling and sapling compositions was done with Non-metric Multidimensional Scaling (NMS). Outlier analysis was used to assess distorting variables for NMS, and Multi-Response Permutation Procedures (MRPP) analysis to differentiate the impact of categorical variables. Sampling success was estimated with rarefaction curves and jackknife estimate of species richness. In the inventory 135 species of trees and shrubs were found. Only some agroforestry related species were dominating. The most species rich were sapling communities in forest habitat. NMS was showing generally low linear correlation between variation of species composition and environmental variables. Solar radiation was having most significance as explaining variable. The most clearly separated in ordination were cacao and forest habitats. The results of seedling and sapling inventory were only partly coinciding with farmers’ knowledge of the tree species occurring on their fields. More research with frequent assessment of seedling cohorts is needed due to natural variability of cohorts and high mortality rate of seedlings.