1,720,969 research outputs found
Absorption, metabolism and protective role of fruits and vegetables polyphenols against gastric cancer
Full text linkGrowing evidence links free radicals to the aging processes, degenerative diseases and cancer, underlying the important role played by some antioxidants, as polyphenols, present in fruits and vegetables, which seem able to counteract the toxic effects induced by oxidative stress. The gastrointestinal tract is continuously exposed to oxidant and antioxidant substances and, in particular in this district, the food rich in antioxidants could exert a protective effect against the risk of cancer. Polyphenols have a direct protective effect on the gastrointestinal tract, detoxifying the Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS), preserving antioxidant proteins and complexing metals. Although polyphenols are a class of antioxidant largely represented in vegetables and fruits, we are still uncertain whether the beneficial effects of a diet rich in plant products, are mainly due to these compounds. Our knowledge does not allow to be sure about which antioxidants are capable of having therapeutic effects, through which mechanism, the exact therapeutic dose or how long they have to be taken to have a significant protective effect. In this review we take into account the most common antioxidants, usually found in the diet and the processes regulating their absorption, metabolism and excretion, in order to elucidate the mechanism that could be responsible for the protection against cancer
Factors influencing epigenetic mechanisms: is there a role for bariatric surgery?
Full text linkEpigenetics is the interaction between the genome and environmental stimuli capable of influencing gene expression during development and aging. A large number of studies have shown that metabolic diseases are highly associated with epigenetic alterations, suggesting that epigenetic factors may play a central role in obesity. To investigate these relationships, we focus our attention on the most common epigenetic modifications that occur in obesity, including DNA methylation and post-translational modifications of histones. We also consider bariatric surgery as an epigenetic factor, evaluating how the anatomic and physiologic modifications induced by these surgical techniques can change gene expression. Here we discuss the importance of epigenetic mechanisms in chronic disease and cancer, and the role of epigenetic disturbances in obesity, with a focus on the role of bariatric surgery
The surgical management of locally advanced well-differentiated thyroid carcinoma. Changes over the years according to the AJCC 8th edition Cancer Staging Manual
Full text linkBackground: Well-differentiated thyroid carcinoma is defined as locally advanced in the presence of an extra thyroid extension, e.g., when the surrounding structures such as the trachea, larynx, esophagus and main blood vessels are invaded by cancer. The 8th edition AJCC Cancer Staging Manual states that this is the main characteristic to evaluate for the staging and consequently for the prognosis in patients over 55 years old. Main body: Distinguishing different forms of locally advanced thyroid cancer is essential, and the various anatomical structures and the clinical and therapeutic consequences must be taken into account. An accurate diagnosis of the organs invaded by thyroid cancer is necessary for the planning of surgical treatment, and both aspects are crucial to improving the patients' survival. Patients affected by thyroid cancer with extra thyroid extension have a poor prognosis and the removal of the entire neoplasm represents a key factor for better disease-free survival. Conclusions: We discuss the changes introduced by the 8th edition AJCC Cancer Staging Manual, in terms of the diagnostic and surgical management of extra thyroid extension, in patients affected by papillary and follicular thyroid cancer
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
Pth after thyroidectomy as a predictor of post-operative hypocalcemia
No full textPost-thyroidectomy hypocalcemia is a frequent complication with significant morbidity, and has been shown to increase hospital stay and readmission rates. The evaluation of serum parathyroid hormone (PTH) levels after thyroidectomy represents a reliable method to predict post-thyroidectomy hypocalcemia, but it remains infrequently used. This retrospective study investigates serum PTH values 3 h after thyroidectomy as a predictor of hypocalcemia. In this study, we enrolled 141 patients aged between 27 and 71 years eligible for total thyroidectomy who presented with multin-odular goiter, suspicious nodule on cytological examination, Graves’ disease, or toxic multinodular goiter. Three hours after total thyroidectomy, 53 patients (37.6%) showed a reduction in serum PTH. Of these patients 75.5% developed hypocalcemia by 24 h after surgery and 100% were hypocalcemic after 48 h (p < 0.001). There was no significant difference attributable to the different thyroid diseases, nor to the age of the patients. PTH at 3 h after total thyroidectomy accurately predicts post-operative hypocalcemia. The early detection of patients at risk of developing post-operative hypocalcemia allows for prompt supplementation of calcium and Vitamin D in order to prevent symptoms and allows for a safe and timely discharge
Nipple-sparing mastectomy long-term outcomes: Early and late complications
No full textBackground and Objectives: The surgical choice treatment of the breast cancer mostly depends on the stage of the disease. In the last years, breast cancer surgery has moved from being destructive to being more respectful of the anatomical and physiological integrity of the gland. The aim of the breast surgery should be finalized to obtain the best aesthetic and functional results, respecting the principles of oncologic radicality. The present study is a retrospective analysis aimed to evaluate the long-term outcomes of a conservative technique like the nipple-sparing mastectomy. Materials and Methods: We observed 894 patients with a median age of 47.5 years old, underwent nipple-sparing mastectomy between 2002-2017. The data acquired include population and tumor characteristics, patient reconstructive outcomes, including locoregional, regional, and distant metastases; other variables, among nipple-areola complex necrosis and infection were collected. Results: The complications detected were considered as “early” within 1 month later the nipplesparing mastectomy or “late” after this time. The overall complications rate (early and late) and the overall survival and the relapses detected by this study were comparable with those reported in the literature. In order to identify factors that correlate with complications, either early or later, it has been processed an evaluation of the univariate analysis showing adjuvant chemotherapy as the only predictive factor for late complications, while we encountered no predictors for early complications. Conclusions: The present study adds to the data already present in literature, demonstrating that the nipple-sparing mastectomy is a safe procedure, providing good oncological and aesthetic results in patients carefully selected
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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