1,721,137 research outputs found
CLEAR CELL-PAPILLARY RENAL CELL CARCINOMA
Full text linkIl carcinoma renale papillare a cellule chiare e il carcinoma renale con stroma leiomuscolare sono due entità recentemente descritte in letteratura, a comportamento biologico non aggressivo e composte da elementi a citoplasma chiaro e basso grado nucleare, la cui distinzione dai principali istotipi renali e in particolare dal carcinoma renale a cellule chiare di tipo convenzionale risulta spesso complessa.
In questa tesi sono stati studiati 14 carcinomi renali papillari a cellule chiare e 7 carcinomi renali con stroma leiomuscolare, utilizzando un ampio pannello immunoistochimico e diverse metodiche di biologia molecolare, allo scopo di definirne maggiormente i caratteri comuni e permettere una loro distinzione più efficace dai più comuni istotipi tumorali renali.
Entrambe le entità descritte hanno presentato diffusa espressione di CK7, CAIX e costante negatività per AMACR. E’ stata inoltre evidenziata la frequente positività per i marcatori 34βE12 e GATA3. I tumori hanno evidenziato inoltre un profilo genetico stabile, l’assenza di alterazioni del gene VHL e di perdita del cromosoma 3p. Un solo caso, con caratteristiche morfologiche e in parte immunofenotipiche e genetiche del gruppo dei carcinomi renali papillari a cellule chiare, ha presentato negatività per 34βE12, GATA3 e presenza di alterazioni a carico del gene VHL ed è pertanto stato riclassificato come carcinoma renale a cellule chiare.
L’insieme dei caratteri descritti, comuni ai carcinomi renali papillari a cellule chiare e a quelli con stroma leiomuscolare, permettono di distinguerli dagli istotipi renali “convenzionali” e di ipotizzare una loro origine comune. Tuttavia, la presenza di casi con caratteri in parte sovrapponibili al carcinoma renale a cellule chiare sottolinea la necessità dell’utilizzo di più metodiche diagnostiche per loro il riconoscimento nella pratica clinica.Clear cell papillary renal cell carcinoma (CCPRCC) is renal neoplasm that has been recently proposed to be added to the current WHO classification of renal tumors. We collected and described a series of these neoplasms, in order to get insights to their clinico-pathological and molecular profiles.
We identified 14 CCPRCC. A first level of Immunohistochemical analysis was performed using CK7, CD10, AE1/AE3, alpha-methylacyl-CoA racemase, PV, S100A1, α-SMA, caldesmon and desmin. We also performed FISH analysis using probes for chromosome 3 and 3p25, array CGH, VHL sequencing and methylation analysis on a part of the cases. Than with a second level of immunoistochemical analysis, we investigated the immunoexpression of 34βE12, CK1, CK5, CK10, CK14 and GATA3, looking for specific markers.
The mean age of the patients was 61, including 9 males and 5 females. The average tumor diameter was 2,62 cm. CCPRCC presented a thick encapsulation and a tubule-papillary or tubule-cystic morphology composed of clear cells with low-grade nuclei. With the first level of immunoistochemical analyses all cases were positive for CK7 and AE1-AE3 and negative for P504S, Parvalbumin, HMB45 and cathepsin K; 75% and 62% of cases were positive respectively for CD10 and S100A1. No deletion of chromosome 3p, significant VHL methylation or changes in copy number was detected in any case, whereas only one CCPRCC showed VHL mutation and presented deletions in chromosome 3 and 6 at CGH analysis.
The second level immunoistochemical analysis showed that 13 of 14 cases of CCPRCC express 34βE12. The immunoexpression of CK14 had the same result of 34βE12. All cases were negative for Ck1 and CK10; only 4 cases of CCPRCC were positive for CK5. GATA3 was expressed in 7 of 13 (54%) cases of CCPRCC.
Comparing as control the immunoexpression of 292 cases of conventional clear cell RCC 34βE12 (or CK14) was expressed in 0,3% and GATA3 was expressed in 1% of the cases giving to them a strong specific meaning.
We concluded that CCPRCC show strong and diffuse positivity for CK7 and do not show 3p deletion, VHL mutation or methylation abnormalities. These tumors show a genomic stability after wide whole genomic analysis.
We propose the immunoistochemical markers 34βE12 (or CK14) and GATA3 as specific markers useful for the identification of these distinct renal neoplasms
INTEGRAZIONE TRA MODELLI DI SIMULAZIONE COLTURALE, PREVISIONI METEO STAGIONALI E DATI PROSSIMALI PER ORIENTARE LE CONCIMAZIONI A DOSAGGIO VARIABILE
No full textLe concimazioni azotate sono uno degli aspetti più importanti dell’agricoltura di oggi. Negli scorsi decenni, diverse metodologie, legate ad informazioni derivanti da sensori prossimali e remoti, sono state proposte per una migliore gestione dell’azoto, e per migliorarne l’efficienza d’uso. I modelli di simulazione colturale sono stati utilizzati per definire il potenziale produttivo di un’area, e, in funzione di questo, dosaggi ottimali di azoto da apportare in maniera sito-specifica. Ovviamente, le stime fatte da un modello di simulazione colturale dipendono in buona parte dal dataset meteo che viene utilizzato. L’utilizzo di dataset meteo climatologico, dove 20-100 anni di dati meteo storici vengono forniti al modello, risulta appropriato quando le variabili meteo osservate (temperatura minima e massima, radiazione solare e precipitazione) non si discostano molto dai valori medi storici. Nel caso contrario, il modello andrà a sovrastimare o sottostimare lo sviluppo della coltura. Per cercare di aumentare l’accuratezza delle informazioni meteo fornite al modello, spesso si ricorre a dataset meteo che sono l’integrazione di dati osservati e previsioni stagionali.
Nel presente lavoro di tesi, che viene presentato come una collezione di articoli, tre principali aspetti sono stati studiati. Nel primo capitolo, il modello di simulazione DSSAT è stato utilizzato per simulare la crescita e lo sviluppo del frumento tenero, secondo due diverse metodologie: (i) il modello è stato utilizzato con un dataset meteo climatologico (dal 1992 al 2018), e (ii) il modello è stato utilizzato con un dataset che combinava dati meteo osservati, fino alla data di concimazione, e previsioni stagionali, dalla data di concimazione in poi. Rese più elevate, maggior contenuto proteico della granella e migliori efficienze d’uso dell’azoto hanno contraddistinto le metodologie basate sul modello di simulazione.
Nel secondo capitolo, il modello è stato utilizzato con le stesse due metodologie testate su frumento, in questo caso su mais. In questo caso, il modello non ha portato a performance consistentemente migliori rispetto alla concimazione uniforme, a causa di: (i) sensori prossimali utilizzati in fase troppo precoce, portando alla definizione di una minima parte della variabilità spaziale; (ii) frequenza ed entità degli eventi piovosi osservati non presente né nel dataset climatologico né in quello previsionale.
Nel terzo capitolo, una metodologia di auto calibrazione del modello di simulazione è stata testata su frumento tenero e mais. I risultati ottenuti dalla cultivar auto calibrata, da quella calibrata manualmente, e da una cultivar di default sono stato confrontati con i valori misurati di biomassa, azoto assimilato, leaf area index, e produzione finale. La cultivar auto calibrata ha mostrato le migliori performances, suggerendo che la seguente metodologià potrà essere utilizzata per fornire calibrazioni robuste e veloci sia su mais che su frumento.Nitrogen (N) fertilization is crucial in today’s crop production. Over the last decades, several proximal and remote-sensing-based approaches have been proposed to improve nitrogen use efficiency (NUE). In addition, crop simulation models (CSMs) have been utilized to determine yield potential and optimal N fertilization rates, considering the weather's effect during a given growing season. In the past, CSMs have been run using datasets of weather variables observed over 20 to 100 years (historical weather data). Historical data works well when the observed weather is close to the historical average but under or overestimates the crop's actual crop production, and N needs when outlier conditions occur. To this, crop models have been run using a combination of the observed and seasonal forecasts.
In this thesis work, presented as a collection of articles, three main aspects were evaluated across three years of experiments. The first experiment tested two different crop model-based approaches in winter wheat. The Decision Support System for Agrotechnology Transfer (DSSAT) CSM was run using (i) historical weather data (1992-2018) and (ii) using a combination of observed weather data (up to the fertilization dates) and seasonal weather forecasts integrated with proximal sensing information. Results showed that feeding the CSM with historical and seasonal forecasts had greater yields, protein content and N efficiencies. In particular, coupling the model with in-season plant N estimates captured the spatial variability at the field level and provided the highest N efficiencies.
In the second experiment, the performance of the two aforementioned crop model-based approaches was also evaluated in corn. The DSSAT CSM was run using (i) historical weather data (1992-2018) and (ii) using a combination of observed weather data (up to the fertilization dates) and seasonal weather forecasts integrated with proximal sensing information. The CSM approaches did not consistently outperform uniform fertilization due to two aspects: first, the use of proximal sensing early in the season (at the V6 stage) was able to capture only a limited part of the spatial variability; second, the historical dataset and seasonal forecasts well not represented the observed rainfall timing and amounts, leading to underestimation of the actual N leaching.
In the third experiment, an automatic model calibration (AMC) approach was tested for providing user-independent model calibration in winter wheat and corn. AMC performances were compared, using RMSE and d-index, to those obtained with the manually calibrated and a default cultivar. Biomass, leaf area index, N uptake and grain yields collected over two growing seasons for each crop were the parameters used for the calibration. Results showed that the AMC aligned better to the observed values than the other two cultivars, suggesting AMC could be used for providing accurate, user-independent and less time-consuming cultivar genetic coefficients in corn and winter wheat
Postural Balance, Muscle Strength and History of Falls in Kidney Transplant Recipients. Equilibrio posturale, forza muscolare e storia di cadute nei pazienti nefrotrapiantati
Full text linkBackground. Although post-transplantation improvement in quality of life can lead to increased levels of physical activity, the amount achieved still remain lower than those measured in general health population. Moreover, the prevalence of sarcopenia and frailty is also higher among kidney transplant recipients (KTRs) and seems to occur at a younger age compared to the general population. In particular, postural instability has been identified as one of the main factors that can lead to adverse outcomes such as falls in the elderly; so, it is plausible to speculate that people living with a renal transplant may thus also be at increased risk for falling. Additionally, muscle atrophy, commonly reported in KTRs, has consistently been associated with impaired postural control and increased risk for falling. Finally, the side effects of immunosuppressive therapy, that include central neurologic disorders (tremors) and peripheral neuropathy may also hinder the postural control of KTRs. Starting from these assumptions, the overall aim of this project is to characterized KTRs from the functional point of view. Specifically, the project was set up in three steps: compare the static balance control in KTRs with healthy adults, explore the falls’ risk profile of KTRs population, and finally involve patients in an adapted and personalized training program. At the best of our knowledge, this is the first protocol investigating static balance control in KTRs and the effects of an exercise program on this skill.
Material and Methods. For the three aims were recruited three different samples. The first was composed by 19 KTRs and 19 healthy adults (HA), with same mean height, weight and age, which are the three determinants of static balance. In this protocol were assessed static balance in three different conditions: open eyes (EO), closed eyes (EC) and dual-task (DT). The second sample for the second project aim was composed by 59 KTRs divided in two groups, the first with 20 KTRs with history of falls in the previous year, and the second with 39 non-fallers. For this study were assessed fall efficacy scale (FES), static balance in the same three conditions of the first protocol, upper and lower limb strength respectively with handgrip strength test and isometric and isokinetic tests for knee and ankle muscles. For the third aim project were recruited 31 KTRs. They were involved in an adapted and personalized training program (10 sessions, 1 hour per session, 2 per week) to improve quality of life, strength and balance. Before and after training period patients’ physical function was evaluated using field tests included in the Senior Fitness Test.
Results. The first experiment confirmed that KTRs are generally sedentary, and the differences between KTRs and HA in postural sway in all conditions (EO, EC and DT) reveal that KTRs had higher postural sway scores than HA. Regarding the second study, 20 out of the 59 investigation participants (33.9%) reported at least one fall in the previous year. Our findings, on falling behavior, suggest that the prevalence of falls in KTRs patients is 1.6 to 4.3 times greater than in age-matched healthy people, which is indicative of an increased risk of falling. Moreover, the muscle strength analysis highlighted an overall trend of poorer upper and lower limb strength in fallers compared to non-fallers. Regarding the last part of the project, despite the little number of training sessions and the training period, improvements in all field tests were statistically significant.
Conclusions. Results corroborated the hypothesis that adapted physical activity should be prescribed as preventive therapy in KTRs, because despite the improvements in quality of life derived from the transplantation the risk of falls still remain high and strength level still remain low, increasing the risk of fracture, and accidental falls which may worsen quality of life and the health burden of these patients
Effects of exercise on dual-task ability and balance in older adults: a systematic review.
No full textThe interest in research on exercise and physical activity effects on dual-task performance has grown rapidly in the last decade due to the aging global population. Most of the available literature is focused on exercise benefits for the risk of falls, attention, and gait-speed; however, there is a lack of evidence reporting the exercise effects on balance in healthy older adults during dual-task performance. The objective of this study was to critically review the existing evidence of a potential relationship between exercise and improvement of static and dynamic balance during dual-task in healthy older adults and secondary outcomes in other physical and cognitive indices. A systematic search using online databases was used to source articles. Inclusion criteria included articles classified as randomized controlled trials (RCT), controlled trials (CT) and uncontrolled trials (UT). Moreover, the studies had to include an exercise or physical activity protocol in the intervention. Eight studies met the eligibility criteria and included 6 RCTs, 1 CT, and 1 UT. Several limitations were identified, mainly focused on the lack of a common and standardized method to evaluate the balance during the dual-task performance. Additionally, exercise protocols were extensively different, and generally lacked reporting measures. Preliminary findings show that the current body of evidence does not support that exercises used in these interventions entail clear and noteworthy benefits on static or dynamic balance improvements during dual-task performance. Innovative measures and exercise programs may need to be developed before efficacious screening and treatment strategies can be used in clinical settings
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
The effects of Pilates exercise training on physical fitness and mental health in elderly: a systematic review for upcoming exercise prescription.
No full textIntroduction: Reducing the risk of falls and associated medical costs are a major global health concern in elderly populations. The aim of this systematic review is to summarize and analyze the effects of Pilates exercise training (PET) in elderly populations on fall prevention and the effects on physical fitness, mental health, quality of life and functional autonomy. Methods: Keyword “Pilates” associated with “elderly”, “aging” and “old subjects” were identified as terms for the literature research in Medline bibliographic online database, PubMed
and Scopus. Only studies published in indexed and peer reviewed journals, written in the English language, were considered. The studies had to provide a PET’- intervention and age of participants had to be higher than 59 years. Results: 10 studies were identified, consisting of 6 RCTs, and 4 uncontrolled trials. Participants were mostly female, averaging 5 weeks to 12 months. Overall, PET training showed 80.2% reduction in numbers of falls, improving in static and dynamic balance, strength, walking performance, depression level, quality of life, functional autonomy and elderly population. Discussion: PET training should be considered as a way to improve quality of life of elderly, thanks to the imparted benefits of fall prevention, physical fitness, and mental health. Physicians should recommend this type of training for elderly patients since evidence has shown positive effects in several outcomes including static and dynamic balance, strength, walking performance, depression level, quality of life, functional autonomy and numbers of falls
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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