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31.
The long-term goal of our research is to develop computerized radiographic markers for assessing breast density and parenchymal patterns that may be used together with clinical measures for determining the risk of breast cancer and assessing the response to preventive treatment. In our earlier studies, we found that women at high risk tended to have dense breasts with mammographic patterns that were coarse and low in contrast. With our method, computerized texture analysis is performed on a region of interest (ROI) within the mammographic image. In our current study, we investigate the effect of ROI size and ROI location on the computerized texture features obtained from 90 subjects (30 BRCA1/BRCA2 gene-mutation carriers and 60 age-matched women deemed to be at low risk for breast cancer). Mammograms were digitized at 0.1 mm pixel size and various ROI sizes were extracted from different breast regions in the craniocaudal (CC) view. Seventeen features, which characterize the density and texture of the parenchymal patterns, were extracted from the ROIs on these digitized mammograms. Stepwise feature selection and linear discriminant analysis were applied to identify features that differentiate between the low-risk women and the BRCA1/BRCA2 gene-mutation carriers. ROC analysis was used to assess the performance of the features in the task of distinguishing between these two groups. Our results show that there was a statistically significant decrease in the performance of the computerized texture features, as the ROI location was varied from the central region behind the nipple. However, we failed to show a statistically significant decrease in the performance of the computerized texture features with decreasing ROI size for the range studied.  相似文献   
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Background

Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%–1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents.

Methods

Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre.

Results

3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004).

Conclusions

The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.
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Atopic dermatitis imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, co-morbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of atopic dermatitis, supporting the use of targeted treatments with biologicals. However, there are still many issues that require further clarification. These include the definition of response, strategies to enhance the responder rate, the duration of treatment and its regimen (in the clinic or home-based), its cost-effectiveness and long-term safety. The EAACI Guidelines on the use of dupilumab in atopic dermatitis follow the GRADE approach in formulating recommendations for each outcome and age group. In addition, future approaches and research priorities are discussed.  相似文献   
35.
The receptors for the Fc region of immunoglobulins (FcR) are members of the immunoglobulin superfamily. They are expressed on various hematopoietic cells and constitute a link between humoral and cell-mediated immunity. The activation and downmodulation of immune responses are controlled by signals from activating and inhibitory FcR, expressed on the surface of immune cells. The signaling regions, defined as immunoreceptor-tyrosine-based activation motif and immunoreceptor-tyrosine-based inhibitory motif, are contained within the cytoplasmic domain of FcR or of the adaptor proteins associated with FcR. Activating and inhibitory FcR are usually coexpressed on the surface of the same cell and coengaged by the same ligand, functioning in concert to keep a balanced immune response. Impairment of the functional balance between activating and inhibitory FcR leads either to hyperactivity to foreign and self antigens or to unresponsiveness as seen in many autoimmune diseases and infections. Pathologic conditions in which immunoglobulin-FcR interactions play a major role, as well as the outcome of treatment with intravenous immunoglobulin and monoclonal antibodies, may be influenced by targeting FcR.  相似文献   
36.
Chimerism occurs naturaly throughout gestation and can also occur as a consequence of transfusion and transplantation therapy. It consists of the acquisition and long-term persistence of a genetically distinct population of allogenic cells inside another organism. Previous reports have suggested that feto-maternal microchimerism could exert a beneficial effect on the treatment of hematological and solid tumors in patients treated by PBSCT. In this review we report the mechanism of transplacental fetal stem cell trafficking during pregnancy and the effect of their long-term persistence on autoimmunity, GVHD, PBSCT, cancer and stem cell treatment.  相似文献   
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Five biologicals have been approved for severe eosinophilic asthma, a well-recognized phenotype. Systematic reviews (SR) evaluated the efficacy and safety of benralizumab, dupilumab, mepolizumab, omalizumab and reslizumab (alphabetical order) compared to standard of care for severe eosinophilic asthma. PubMed, Embase and Cochrane Library were searched to identify RCTs and health economic evaluations, published in English. Critical and important asthma-related outcomes were evaluated for each of the biologicals. The risk of bias and the certainty of the evidence were assessed using GRADE. 19 RCTs (three RCTs for benralizumab, three RCTs for dupilumab, three RCTs for mepolizumab, five RCTs for omalizumab and five RCTs for reslizumab), including subjects 12 to 75 years old (except for omalizumab including also subjects 6-11 years old), ranging from 12 to 56 weeks were evaluated. All biologicals reduce exacerbation rates with high certainty of evidence: benralizumab incidence rate ratio (IRR) 0.53 (95% CI 0.39 to 0.72), dupilumab (IRR) 0.43 (95% CI 0.32 to 0.59), mepolizumab IRR 0.49 (95% CI 0.38 to 0.66), omalizumab (IRR) 0.56 (95% CI 0.40 to 0.77) and reslizumab (IRR) 0.46 (95% CI 0.37 to 0.58). Benralizumab, dupilumab and mepolizumab reduce the daily dose of oral corticosteroids (OCS) with high certainty of evidence. All evaluated biologicals probably improve asthma control, QoL and FEV1, without reaching the minimal important difference (moderate certainty). Benralizumab, mepolizumab and reslizumab slightly increase drug-related adverse events (AE) and drug-related serious AE (low to very low certainty of evidence). The incremental cost-effectiveness ratio per quality-adjusted life year value is above the willingness to pay threshold for all biologicals (moderate certainty). Potential savings are driven by decrease in hospitalizations, emergency and primary care visits. There is high certainty that all approved biologicals reduce the rate of severe asthma exacerbations and for benralizumab, dupilumab and mepolizumab for reducing OCS. There is moderate certainty for improving asthma control, QoL, FEV1. More data on long-term safety are needed together with more efficacy data in the paediatric population.  相似文献   
40.
The purpose of this study was to investigate whether the severity of acute pulmonary embolism (PE) could be quantitatively assessed with spiral CT angiography (SCTA). Thirty-six consecutive patients without underlying cardiopulmonary disease and high clinical suspicion of PE underwent prospectively thin-collimation SCTA and echocardiography at the time of the initial diagnosis (T0) and after initial therapy (T1; mean interval of time T1–T2: 32 days). The CT severity score was based on the percentage of obstructed surface of each central and peripheral pulmonary arterial section using a 5-point scale (1: <25%; 2: 25–49%; 3: 50–74%; 4: 75–99%; 5: 100%). The sum of the detailed scores attributed to 5 mediastinal, 6 lobar and 20 segmental arteries per patient led to the determination of central, peripheral and global CT severity scores and subsequent determination of percentages of obstruction of the pulmonary circulation. Echocardiographic severity criteria included the presence of signs of acute cor pulmonale and/or systolic pulmonary hypertension (>40 mm Hg). The SCTA depicted acute PE in all patients at T0 with complete resolution of endovascular clots in 10 patients at T1. At T0, the mean percentage of obstruction of the pulmonary arterial bed was significantly higher in the 22 patients with echocardiographic signs of severity (56±13 vs 28±32%; p<0.001). A significant reduction in the mean percentage of pulmonary artery obstruction was observed in the 19 patients with resolution of echocardiographic criteria of severity between T0 and T1 T0: 57±14%; T1: 7±11%; p<0.001).The threshold value for severe PE on CT angiograms was 49% (sensitivity: 0.773; specificity: 0.214). The mean (±SD) pulmonary artery pressure was significantly higher in the 26 patients with more than 50% obstruction of the pulmonary artery bed (45±15 mm Hg) than in the 10 patients with less than 50% obstruction of pulmonary artery bed at T0 (31±11 mm Hg; p<0.01). The CT severity score evaluated in the present study enables quantitative assessment of acute PE severity on spiral CT angiograms, readily applicable in routine clinical practice. Electronic Publication  相似文献   
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