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Per lumina, per limina: percorsi nelle varianti a stampa di Andrea Zanzotto
No full textNell'articolo si presentano e commentano alcune (fino alla raccolta "Pasque") delle varianti a stampa individuate nell'opera poetica di Andrea Zanzotto. Si considerano le diverse edizioni delle raccolte poetiche e alcune plaquettes
Dysregulation of the Arachidonic Acid Pathway in Cystic Fibrosis: Implications for Chronic Inflammation and Disease Progression
Get PDFCystic fibrosis (CF) is the most common fatal genetic disease among Caucasian people, with over 2000 mutations in the CFTR gene. Although highly effective modulators have been developed to rescue the mutant CFTR protein, unresolved inflammation and persistent infections still threaten the lives of patients. While the central role of arachidonic acid (AA) and its metabolites in the inflammatory response is widely recognized, less is known about their impact on immunomodulation and metabolic implications in CF. To this end, here we provided a comprehensive analysis of the AA metabolism in CF. In this context, CFTR dysfunction appeared to complexly disrupt normal lipid processing, worsening the chronic airway inflammation, and compromising the immune responses to bacterial infections. As such, potential strategies targeting AA and its inflammatory mediators are being investigated as a promising approach to balance the inflammatory response while mitigating disease progression. Thus, a deeper understanding of the AA pathway dysfunction in CF may open innovative avenues for designing more effective therapeutic interventions
Transesophageal echocardiography with tissue Doppler imaging in the assessment of global and regional systolic and diastolic right ventricular function in atrial septal defects.
No full textBackground. Evaluation of global and regional right ventricular (RV) systolic and diastolic function in atrial septal defects (ASD) is still a challenging post-surgical clinical problem, especially in adult patients (pts) We investigated whether high frame rate tissue Doppler imaging (TDI, Toshiba corp.) may provide quantitative assessment of RV function in ASD pts.
Methods. Twenty-three pts with ostium secundum ASD, aged 25±9 years, were studied with transesophageal echocardiography. Twelve pts underwent corrective surgery. 11 subjects with no signs of heart disease were used as a control group. ASD pts were classified in 3 groups according to 2D/color Doppler defect and shunt size (group “1” large, group “2” medium, group “3” small). Peak mean systolic (Sw) and diastolic (Ew, Aw) wall velocities were acquired from the 4-chamber view in the myocardia [septum (IVS) and free wall (FW)]. TDI wall velocities during systole (Sa), early relaxation (Ea) and atrial systole (Aa) were also measured in the tricuspid annulus. Satisfactory TDI data could be obtained in all pts at end expiration, independent of quality of RV wall motion.
Results. Compared to controls, group “1” pts had lower mean FW velocities (Sw= 5.5±1.9 vs 8.3±2.1 cm/s – p<0.005 –; Ew=5.8±1.9 vs 9.4±2.2 cm/s – p< 0.001 –; Aw=3.5±1.4 vs 3.6±1.8 cm/s – p=NS –) and lower annulus velocities both in systole and diastole (Sa =5.3±1.3 vs 8.9±1.3 cm/s – p<0.001 – ; Ea = 6.2±2.4 vs 13.3±2.4 cm/s – p< 0.001 – ; Aa = 7.8±2.2 vs 7.1±2.3 cm/s – p=NS – ). Also, group “1” pts had lower mean FW Sw and Ew velocities compared to IVS wall velocities (p < 0.005). Group “2” pts had preserved systolic velocities but decreased regional and annular early diastolic velocities suggesting impaired relaxation (Ea/Aa 0.87±0.28 vs 1.64±0.31 – p<0.0001 – ). Group “3” pts had preserved systolic and diastolic velocities.
Conclusion. Thus, TDI is useful in evaluating systolic and diastolic RV abnormalities, could corroborate the need of surgery in pts with volume overload, and may aid in monitoring RV function during post-surgical followup
Prediction of coronary artery disease by transesophageal echocardiographic assessment of thoracic aorta atherosclerosis
No full textBackground: It has been shown that the presence of aortic atherosclerotic plaques is associated with an increased risk of coronary artery disease and myocardial ischemia. The purpose of the study was to establish the value of combined thoracic aorta atherosclerosis and decreased aortic elastic properties to predict the existence of obstructive coronary artery disease.
Methods: Forty-four patients (pts) aged 46 to 74 years were studied with multiplane transesophageal echocardiography (TEE). Thoracic aorta atherosclerosis was diagnosed by increased echodensity of the intima with well defined atheroma protruding in the aortic lumen. Tissue Doppler imaging (TDI, Toshiba corp.) during TEE was used for the quantification of aortic elastic properties. The descending aorta was visualized in a TEE short axis view at the level of the left atrium and TDI was used for the rates of velocity change (dV/dt) over time. Peak positive dV/dt (dV/dt max, cm2sec-1) was measured. Results were compared to angiographically documented coronary artery stenosis (>50% diameter stenosis of any major branch).
Results: 19/44 pts had proved coronary artery disease (CAD). dV/dt max was 7.82±1.79 in pts without CAD and 4.43±1.34 in pts with CAD (p 3 mm was detected in 17/19 pts with CAD and 5/25 pts without CAD. dV/dt max 3 mm on thoracic aorta had a sensitivity of 92%, specificity of 70% and positive predictive value of 85% for predicting presence of CAD.
Conclusion: Our results indicate that these described combined methods are highly predictive for the existence of obstructive coronary artery disease
Transesophageal echocardiographic assessment of thoracic aorta elastic properties by TDI in patients with Marfan syndrome
No full textBackground: It has been shown that the presence of aortic dilation is associated with an increased risk of aortic dissection in patients with Marfan disease. The purpose of the study was to establish the value of combined thoracic aorta dilation and decreased aortic elastic properties to assess the severity of aortic disease in patients with Marfan syndrome.
Methods: Fifteen patients (pts) with Marfan syndrome (Beighton criteria) aged 13 to 42 years were studied with multiplane transesophageal echocardiography (TEE). 6/15 pts had surgery for aortic dissection. Tissue Doppler imaging (TDI, Toshiba corp.) during TEE was used for the quantification of aortic elastic properties. The descending aorta was visualized in a TEE short axis view at the level of the left atrium and TDI was used for the rates of velocity change (dV/dt) over time. Peak positive dV/dt (dV/dt max, cm2sec-1) was measured.
Results: Descending thoracic aorta dilation (>30mm) was present in 11/15 pts. dV/dt max was 7.97±1.82 in pts without surgery and 4.39±1.47 in pts with surgery (p 40 mm was detected in 5/6 pts with surgery and 3/25 pts without surgery. dV/dt max 40 mm had a sensitivity of 91%, specificity of 73% and positive predictive value of 83% for predicting aortic dissection.
Conclusion: Our results indicate that these described combined methods are highly predictive for the development of aortic dissection in Marfan syndrome and should suggest aggressive treatment
Evaluation of aortic wall mechanics in Marfan syndrome by transesophageal tissue Doppler echocardiography
No full textBackground: It has been described that the presence of aortic dilation is associated with an increased risk of aortic dissection in patients with Marfan disease. The aim of our study was to investigate the value of combined thoracic aorta dilation and decreased aortic elastic properties in assessing the severity of aortic disease in patients with Marfan syndrome.
Methods: Sixteen patients (pts) with Marfan syndrome (Beighton criteria) aged 13 to 45 years were studied with multiplane transesophageal echocardiography (TEE). 6/16 pts had surgery for aortic dissection. Tissue Doppler imaging (TDI, Toshiba corp.) during TEE was used for the quantification of aortic elastic properties. Eleven age-matched healthy subjects who had normal findings at TEE served as controls. The descending aorta was visualized in a TEE short axis view at the level of the left atrium. TDI tracing displayed accelerated expansion of the aortic wall followed by a slow deceleration, a plateau and then a rapid deceleration into diastole. Acceleration time (AT, msec), maximum wall expansion velocity (Vmax, cm/sec), and wall contraction velocities (cm/sec) were determined.
Results: Descending thoracic aorta dilation (>30mm) was present in 12/16 pts. Vmax values were significantly decreased compared to controls (p 40 mm had a sensitivity of 92%, specificity of 80% and positive predictive value of 77% for predicting aortic dissection.
Conclusion: Our results show that this combined 2D/TDI method is highly predictive for the development of aortic dissection in Marfan syndrome and should suggest aggressive treatment
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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