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Background Although ceramic brackets have been extensively used for decades in orthodontics there is not till today any study focusing on the possible deterioration of mechanical properties after in vivo ageing. Objectives To determine whether the mechanical properties of alumina orthodontic brackets change after intraoral ageing thereby assessing the validity of a theoretical model established for the performance of ceramics in wet environments. Materials and methods Two alumina brackets, one single crystal (Radiance, American Orthodontics, Sheboygan, WI) and one polycrystalline (Clarity, 3M, St. Paul, MN) were included in this study. Ten brackets for each group were collected from different patients after a minimum of 3-month intraoral exposure, whereas as-received brackets of the same manufacturers were used as controls. The specimens were subjected to Raman spectroscopy and were then embedded in epoxy resin and metallographic ground and polished. The mechanical properties of four groups (radiance control: RAC, radiance-retrieved RAR, clarity control: CLC and clarity-retrieved CLR) were determined using instrumented indentation testing according to ISO 14577-2002. The mechanical properties tested were Martens hardness (HM), indentation modulus (E IT), the ratio of elastic to total work, commonly known as elastic index (η IT), and fracture toughness (K IC). The numerical results were statistically analysed employing two-way analysis of variance (ANOVA) and Tukey multiple comparison test at a = 0.05. Results Raman analysis revealed that both brackets are made of a-Al2O3 (corundum). No statistically significant differences were found for HM (N/mm2): RAC = 7249 (1507), RAR = 6926 (1144), CLC = 8052 (1360), CLR = 7390 (2393), or for E IT (GPa): RAC = 141 (27), RAR = 139 (23), CLC = 139 (28), CLR = 131 (47). However, significant differences were identified between the two alumina brackets tested for η IT (%): RAC = 55.7 (4.2), RAR = 54.0 (3.5), CLC = 62.5 (4.4), CLR = 61.8 (4.7), while K IC was measured only for the polycrystalline bracket (Clarity) because of the complicated fractured pattern of the single-crystal bracket. Both brackets share equal HM and E IT before and after orthodontic intraoral ageing. Limitations Whereas the study assessed the changes after intraoral exposure per theoretical model, which describes the reduction of critical stress to induce fracture after wetting, long-term intraoral ageing could have induced more pronounced effects. Conclusions/Implications The results of this study indicate that 3 months of intraoral ageing do not change the mechanical properties of single-crystal and polycrystalline orthodontic brackets tested, thus indicating that the Griffith theory may not be applied to the case of manufactured ceramic brackets owing possibly to internal defects. [ABSTRACT FROM AUTHOR]

There is a complex and not fully elucidated association between pulmonary arterial hypertension (PAH) and coagulation disorders. The goal of this study was to evaluate platelet function, coagulation and fibrinolysis in PAH patients at diagnosis, before PAH-specific treatment initiation. We enrolled 20 healthy controls and 30 PAH patients (20 with connective tissue disease (CTD-PAH) and 10 idiopathic (iPAH)). None of the participants was on any antiplatelet or anticoagulation therapy. Blood samples from PAH patients were collected during the initial right heart catheterization. All subjects were assessed with platelet function analyzer-100 (PFA-100), epinephrine (Epi) and ADP-induced light transmission aggregometry (LTA), thromboelastometry (ROTEM) and endogenous thrombin potential (ETP). Our results showed that Epi and ADP-LTA values were significantly lower in newly diagnosed PAH patients compared to controls. Disaggregation was present in 73% of patients, a characteristic not seen in healthy individuals. In ROTEM assay, CT and CFT measurements were significantly higher and a angle lower compared to controls. ETP testing revealed significantly reduced outcomes in AUC, Cmax and Tmax. When CTD-PAH and iPAH patient groups were compared, iPAH ADP-LTA values were significantly decreased compared to CTD-PAH. In conclusion, newly diagnosed PAH patients presented with decreased platelet aggregation, clot propagation and thrombin generation, along with delayed initiation of the coagulation process. These hemostatic deficits could indicate an "exhaustion" of the coagulation process that could be caused by endothelial dysfunction and chronic activation of the procoagulant pathways. Further studies are warranted to confirm these laboratory findings and assess their potential clinical significance. [ABSTRACT FROM AUTHOR]

Objectives To evaluate the hard tissue and facial profile changes in matched extraction and non-extraction Class I patients by the use of geometric morphometrics. Subjects and Methods From a parent sample of 542 Class I patients, previously subjected to discriminant analysis, a subsample of 68 borderline cases was obtained, 34 treated with extraction and 34 without extraction of 4 first premolars. Geometric morphometric methods (Procrustes superimposition and Principal Component Analysis) were applied on cephalometric tracings to assess the validity of the discriminant analysis in successfully identifying a morphologically homogeneous group and to evaluate inter- and intra-group skeletal and facial profile shape changes. Results No significant pre-treatment shape difference between the two groups was found, thus validating the discriminant analysis. The non-extraction group showed increase in hard tissue facial height (P < 0.001), with slight lower lip retrusion and upper lip protrusion (P = 0.027). The extraction group showed retraction of the hard tissue and facial profile outline (P < 0.001). Permutation tests for post-treatment inter-group differences resulted in P = 0.054 for the soft tissue outline and P = 0.078 for the hard tissue skeletal component. Conclusions The evidence indicates that borderline cases treated with four premolar extractions will exhibit lip retrusion compared to non-extraction treatment. [ABSTRACT FROM AUTHOR]

Langerhans cell histiocytosis (LCH) is a multisystemic disease affecting mainly the skeleton and the lungs. It is an uncommon interstitial lung disease whose radiological findings are characterized by centrilobular nodules and cysts of varying sizes of mid to upper lung distribution. Pulmonary LCH can be associated with pulmonary hypertension (PH) which is often severe. We report two cases with Pulmonary Langerhans cell histiocytocis who were referred to our pulmonary hypertension clinic because of echocardiographic signs of severe PH. Right heart catheterization confirmed the presence of precapillary PH in both patients; however in one patient the severity of PH was disproportional to lung disease, as revealed from pulmonary function tests and highresolution computed Tomography chest findings, suggesting pulmonary vascular involvement. We would like to emphasize the wide spectrum of Pulmonary LCH - associated PH and the rationale to treat some patients with specific PAH medication. [ABSTRACT FROM AUTHOR]

Chronic Thromboembolic Pulmonary Hypertension (CTEPH) is a rare disease with poor prognosis if left untreated, characterized by pulmonary vascular bed obstruction due to unresolving thromboembolic material. The Hellenic pulmonary hypertension registry (HOPE) was launched in Greece in early 2015 and enrolls patients from all pulmonary hypertension subgroups in Greece. In total, 98 patients with CTEPH were enrolled from January 2015 until November 2019. Of these patients, 55.1% represented incident population, 50% were classified in the World Health Organization functional class II and 49% had a history of acute pulmonary embolism. The median values of pulmonary vascular resistance (PVR) and cardiac index were 7.4 (4.8) WU and 2.4 (1.0) L/min/m2, respectively, the mean diffusing capacity for carbon monoxide was 74.8 ± 20.6%, the median 6-minute walk distance was 347 (220) meters and the median value of N Terminal-pro brain natriuretic peptide was 506.0 (1450.0) pg/mL. In total, 60.2% of the patients were under pulmonary arterial hypertension-targeted therapy at the time of enrolment; specifically, riociguat was received by 35.7% of the patients and combination therapy was the preferred strategy for 16% of the patients. In total, 74 patients were evaluated for pulmonary endarterectomy (PEA), 34 (45.9%) were assessed as operable but only 23 of those (31.1%) finally underwent PEA. The remaining 40 patients were ineligible for PEA according to the operability assessment and 13 (17.6%) of them underwent balloon pulmonary angioplasty. The age of the non-operable patients was significantly higher than the operable patients (p < 0.001), while there was no significant difference with regard to the history of coagulopathies between the operable and non-operable patients (p = 0.33). [ABSTRACT FROM AUTHOR]

Background: Whether past history of solid stage I/II inactive cancer has an impact on 28-day mortality of sepsis remains unclear. We aimed to determine the impact of history of stage I or II solid tumor malignancy in complete remission the last 3 years on sepsis outcome.Methods: Using the database of the Hellenic Sepsis Study Group from 1553 patients with sepsis admitted in the ICU, 83 patients with sepsis by Sepsis-3 definition with past-history of stage I/II inactive solid malignancy the last 3 years were depicted. A comparator group of 83 patients fully matched for age, severity, type of infection and comorbidities was selected by propensity score matching.Results: Mortality after 28 days was 37.3% in the comparator group and 54.2% in the solid tumor stage I/II group (odds ratio for death 1.98; p: 0.030). Following step-wise forward Cox regression analysis, septic shock (hazard ratio 1.80), acute renal injury (hazard ratio 2.06), history of coronary heart disease (hazard ratio 0.36) and history of stage I/II solid tumor malignancy (hazard ratio 1.79) were the only independent variables associated with 28-day mortality. Serum levels of procalcitonin and of soluble urokinase plasminogen activator receptor were similar between the two groups of comparisons.Conclusions: Past history of stage I/II solid malignancy is an independent risk factor for unfavorable outcome from sepsis the first 28 days. [ABSTRACT FROM AUTHOR]

Background: Whether past history of solid stage I/II inactive cancer has an impact on 28-day mortality of sepsis remains unclear. We aimed to determine the impact of history of stage I or II solid tumor malignancy in complete remission the last 3 years on sepsis outcome., Methods: Using the database of the Hellenic Sepsis Study Group from 1553 patients with sepsis admitted in the ICU, 83 patients with sepsis by Sepsis-3 definition with past-history of stage I/II inactive solid malignancy the last 3 years were depicted. A comparator group of 83 patients fully matched for age, severity, type of infection and comorbidities was selected by propensity score matching., Results: Mortality after 28 days was 37.3% in the comparator group and 54.2% in the solid tumor stage I/II group (odds ratio for death 1.98; p: 0.030). Following step-wise forward Cox regression analysis, septic shock (hazard ratio 1.80), acute renal injury (hazard ratio 2.06), history of coronary heart disease (hazard ratio 0.36) and history of stage I/II solid tumor malignancy (hazard ratio 1.79) were the only independent variables associated with 28-day mortality. Serum levels of procalcitonin and of soluble urokinase plasminogen activator receptor were similar between the two groups of comparisons., Conclusions: Past history of stage I/II solid malignancy is an independent risk factor for unfavorable outcome from sepsis the first 28 days.

Objectives: To evaluate the hard tissue and facial profile changes in matched extraction and non-extraction Class I patients by the use of geometric morphometrics., Subjects and Methods: From a parent sample of 542 Class I patients, previously subjected to discriminant analysis, a subsample of 68 borderline cases was obtained, 34 treated with extraction and 34 without extraction of 4 first premolars. Geometric morphometric methods (Procrustes superimposition and Principal Component Analysis) were applied on cephalometric tracings to assess the validity of the discriminant analysis in successfully identifying a morphologically homogeneous group and to evaluate inter- and intra-group skeletal and facial profile shape changes., Results: No significant pre-treatment shape difference between the two groups was found, thus validating the discriminant analysis. The non-extraction group showed increase in hard tissue facial height (P < 0.001), with slight lower lip retrusion and upper lip protrusion (P = 0.027). The extraction group showed retraction of the hard tissue and facial profile outline (P < 0.001). Permutation tests for post-treatment inter-group differences resulted in P = 0.054 for the soft tissue outline and P = 0.078 for the hard tissue skeletal component., Conclusions: The evidence indicates that borderline cases treated with four premolar extractions will exhibit lip retrusion compared to non-extraction treatment., (© The Author(s) 2018. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Diaphragmatic ultrasonography has been recently considered as a new weaning predictor method. Previous studies checked diaphragmatic excursion and thickness during quiet or deep breathing in unselected populations of critically ill patients. Our study aimed to investigate diaphragmatic excursion during quiet and unassisted breathing, in comparison to standard predictor tools, such as Rapid Shallow Breathing Index (RSBI) and Maximal Inspiratory Pressure (Pimax), in patients with difficult and/or prolonged weaning., Methods: Patients with difficult and/or prolonged weaning, who met the criteria for spontaneous breathing trial, were assessed. The excursion of each hemidiaphragm (DEx) was evaluated by B-mode and M-mode ultrasonography while patient was on quiet breathing and at supine position. RSBI and Pimax were simultaneously recorded and weaning outcome was recorded., Results: Thirteen male and fourteen female patients were included. DEx [median and interquartile range, mm] was 14 (8.5-22) for the right hemidiaphragm (RDEx) and 12 (7-23) for the left (LDEx). We found no difference in DEx between sexes. Among the four weaning predictor tools, LDEx at a cut-off 10 mm was the best index to predict weaning success (sensitivity 86%, specificity 85%, Negative Predictive Value 94%). The optimal cut-off values, as determined by the area under the receiver operating characteristic curve, were 10 mm for RDEx, 7 mm for LDEx, 57 breaths/min/L for RSBI and -20 cmH2O for Pimax., Conclusions: Our results suggest that DEx threshold of 10 mm and 7 mm for right and left hemidiaphragms respectively could be used as adjunct tool in the predictive algorithm of weaning in difficult to wean patients.