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Caratterizzazione clinica, diagnostica e morfologica di particolari forme di malattie infiammatorie del pancreas: pancreatite associata a mutazioni geniche e pancreatite autoimmune
No full textIntroduzione: La ricerca svolta nel corso di questo dottorato è stata orientata verso la valutazione della pancreatite associata a mutazioni geniche e della pancreatite autoimmune.
Nell’ambito dello studio della pancreatite associata a mutazioni geniche, l’indirizzo di ricerca si è orientato (1) al confronto tra l’evoluzione clinico-morfologica di queste forme rispetto alle pancreatiti ad altra eziologia e (2) alla valutazione delle caratteristiche radiologiche delle calcificazioni pancreatiche che si osservano nelle fasi più avanzate di malattia.
Nell’ambito dello studio della pancreatite autoimmune, l’indirizzo di ricerca si è orientato (3) alle caratteristiche cliniche e all’evoluzione nel tempo della malattia, differenziando la forma diffusa da quella formante massa e (4) alla ricerca di un marcatore sierico.
Risultati e conclusioni:
(1) Studio delle mutazioni dei geni CFTR, SPINK1 e PRSS1 con valutazione clinica radiologica e funzionale di 34 pazienti portatori di mutazioni geniche confrontati con 164 pazienti affetti da pancreatite cronica e negativi ai tests genetici.
Conclusioni:
a.L’outcome clinico dei pazienti affetti da pancreatite cronica associata a mutazioni geniche sembra essere differente da quanto osservato nei pazienti affetti da pancreatite cronica ad altra eziologia.
b.Lo sviluppo di insufficienza pancreatica esocrina ed endocrina sembra essere più tardivo nel gruppo di pazienti affetti da positivi ai tests genetici.
c.L’alcol, anche in piccole quantità, ed il fumo di sigaretta influenzano in modo considerevole lo sviluppo di calcificazioni pancreatiche nei pazienti con mutazioni geniche.
(2) Valutazione del ruolo della TC Addome nell’individuazione di calcoli con aspetto “bull’s eye” per distinguere i pazienti affetti da pancreatite cronica associata a mutazioni geniche rispetto a quelli con tests genetici negativi.
Conclusioni: il riscontro alla TC di calcoli di grandi dimensioni (>15 mm) e struttura a “bull’s eye” è fortemente suggestivo della presenza di una mutazione genica associata alla pancreatite cronica, in particolare in assenza di altri fattori eziopatogenetici.
(3) Analisi delle caratteristiche cliniche e radiologiche di una serie prospettica di pazienti affetti da AIP (87 tot., di cui 55 affetti da forma focale di malattia e 32 da forma diffusa), seguiti per un lungo periodo di tempo, ponendo attenzione tra le due forme di malattia.
Conclusioni:
a.La forma focale e quella diffusa presentano differenze cliniche significative.
b.La colite ulcerosa è la patologia autoimmune più frequentemente associata alla pancreatite autoimmune.
c.Le ricorrenze di malattia sono più frequenti nei pazienti anziani, affetti dalla forma focale, in particolare se fumatori ed in presenza di elevati livelli di IgG4 sieriche.
d.L’insorgenza d’insufficienza pancreatica esocrina ed endocrina non è correlata alla chirurgia pancreatica e sembra essere progressiva, suggerendo la natura cronica della malattia, anche in assenza di segni e sintomi clinici.
(4) Identificazione di un marcatore sierico in grado di discriminare la pancreatite autoimmune focale dall’adenocarcinoma pancreatico. A tale scopo è stato utilizzato un approccio di biologia molecolare già applicato con risultati soddisfacenti nello studio di altre malattie autoimmuni.
Conclusioni: abbiamo identificato un peptide di 7 amminoacidi, che presenta una analogia con una proteina dell’H.pylori, riconosciuto da quasi tutti i sieri dei pazienti affetti da pancreatite autoimmune. Tale peptide è in grado di discriminare questi pazienti da quelli affetti da altre patologie infiammatorie e neoplastiche pancreatiche, in particolare da quelli affetti da adenocarcinoma del pancreas, e da altre patologie autoimmuni.Introduction: the aim of the studies was to evaluate chronic pancreatitis associated to gene mutations and autoimmune pancreatitis.
In chronic pancreatitis associated to gene mutations, the search was addressed to evaluate (1) clinical-morphological evolution and (2) radiological characteristic of pancreatic calcifications compared with chronic pancreatitis negative to genetic tests.
In autoimmune pancreatitis, the search was addressed (3) to evaluate clinical aspects and evolution of diffuse and focal forms and (4) to find a serological marker of the disease.
Results and conclusions:
(1) Radiological, clinical and functional investigation of 34 patients suffering from chronic pancreatitis associated with CFTR, SPINK1 and PRSS1 genes mutations compared with 164 patients with chronic pancreatitis and negative genetic tests.
Conclusions:
a.The clinical outcome of patients suffering from chronic pancreatitis associated with genes mutations seems to be different from those with negative genetic tests.
b.The onset of pancreatic exocrine and endocrine insufficiency seems to be delayed in patients with chronic pancreatitis and gene mutations.
c.Alcohol, even in small quantities, and cigarette smoking consumption enhance the onset of pancreatic calcifications in patients with chronic pancreatitis associated with gene mutations.
(2)Role of CT in the evaluations of the presence of pancreatic calcifications to distinguish 16 patients suffering from chronic pancreatitis associated with gene mutations from 32 with negative genetic tests.
Conclusions: diameter of pancreatic calcifications (>15 mm) and “bull’s eye” aspects are strongly correlated with positive genetic tests.
(3) Clinical and radiological characteristic of patients suffering from 87 patients suffering from autoimmune pancreatitis (55 of focal and 32 of diffuse type), followed for a long period of time.
Conclusions:
a.Focal and diffuse type of the disease are clinically different.
b.Ulcerative colitis is the most common autoimmune disease associated with autoimmune pancreatitis.
c.Recurrences of the disease are more commonly observed in aged patients, with focal form, in smokers and in patients with elevated serum level of IgG4.
d.The onset of exocrine and endocrine pancreatic insufficiency is not related to surgery and seems to be progressive, suggesting that the process is chronic even in the absence of clinical signs.
(4) Identification of a serological marker able to discriminate between autoimmune pancreatitis and pancreatic adenocarcinoma.
Conclusions: a 7 amminoacids-peptide, that present a homology with a H.pylori protein, was recognized by serum of patients suffering from autoimmune pancreatitis. This peptide is able to discriminate these patients from those suffering from inflammatory and neoplastic pancreatic diseases, particularly from pancreatic adenocarcinoma, and from other autoimmune diseases
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Exocrine and Endocrine Pancreatic Function in 21 Patients Suffering from Autoimmune Pancreatitis before and after Steroid Treatment
No full textBackground/Aim: Autoimmune pancreatitis (AIP) responds rapidly and dramatically to steroid therapy. The aim of this study was to evaluate pancreatic exocrine and endocrine function in patients suffering from AIP both before and after steroid therapy. Patients andMethods: Fecal elastase 1 and diabetes were evaluated before steroid therapy and within 1 month of its suspension in 21 patients (13 males and 8 females, mean age 43 ± 16.5 years) diagnosed as having AIP between 2006 and 2008. Results: At clinical onset, fecal elastase 1 was 107 ± 126 μg/g stool. Thirteen patients (62%) showed severe pancreatic insufficiency (200 μg/g stool). Before steroids, diabetes was diagnosed in 5 patients (24%), all of whom had very low levels of fecal elastase 1 (<19 μg/g stool). Following steroids, fecal elastase 1 increased in all patients (237 ± 193 μg/g stool) and observed levels were significantly higher than those seen before steroids (p = 0.001). Conclusions: Patients suffering from AIP display exocrine and/or endocrine pancreatic insufficiency at clinical onset. These insufficiencies improve after steroid therapy
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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