1,720,966 research outputs found
Gastric Cancer: Molecular Pathology State
No full textDespite the progressive decrease observed in the past fifty years, gastric cancer (GC) is the
fourth of the world rankings incidence of various types of cancer and is the second as a cause
of cancer-related death. There is distinct geographical variation in gastric cancer incidence with
the highest rates reported from Japan, Korea and Eastern Asia. Other high incidence areas are
Eastern Europe and parts of Latin America, while Western Europe, Africa, Australia and the
US generally have low incidence rates. In the last decade there has been a downward trend in
the incidence and mortality from this cancer. The reasons are to be found in the improvement
of food both as regards its preservation procedures and the variability in the diet and for the
decrease of infection by Helicobacter pylori (H. pylori). H. pylori infection is strongly associated
with risk for stomach cancer. Likely, this association is supported by the strong link between
this bacterium infections and precancerous lesions, including chronic atrophic gastritis and
dysplasia. The development of gastric cancer is characterized by multistage process in which
several alterations of genetic and epigenetic nature accumulate. These alterations are mainly
related to abnormalities of growth factors and receptors, DNA mismatch repair genes,
angiogenic factors, transcription factors, adaptor proteins, cell cycle regulators, and many
other macromolecular cell components. All these abnormalities identify from one side the
molecular and biological aspect of gastric cancer cells and from the other might suggest
possible strategies for therapeutic intervention
An overview on factors underlying gastric cancer; strategies for its management with particular reference to diet
No full textThe incidence of stomach cancer and the number of victims of this disease have decreased dramatically over the
last 60 years. However, gastric cancer still remains a very serious disease that requires further studies to enlarge
knowledge on its causes and to prevention methods. To date, the causes of gastric cancer are still not yet well
known but it is clear that some people are more prone than others to develop this disease. Gastric cancer affects
mostly adults aged 55 and over and men in percentage double than women. Stomach ulcer apparently does not
increase the risk of gastric cancer however, Helicobacter pylori, usually due to inflammation and gastric ulcers, may
be an important risk factor for this disease. Moreover, patients who have undergone stomach surgery or suffering
from pernicious anemia, achlorhydria or atrophic gastritis (that typically produce a reduction in the amount of acid)
are subject to a higher risk of gastric cancer. Exposure in workplaces to certain agents such as dust or fumes is
linked to a higher risk than average of developing stomach cancer. Smoking also contributes to increase this risk.
Moreover, epidemiological studies and animal models, conducted for years, have shown that some eating habits can
increase the risk of cancer. Other studies instead report that fresh foods (especially fruits and vegetables) play a
protective function against gastric cancer. For this reason, this paper provides an overview of the possible causes of
gastric cancer and the different therapeutic approaches, focusing in particular on the effects of diet
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
Role of Gastrokine 1 in Gastric Cancer: A Potential Diagnostic Marker and Antitumor Drug
No full textGastric cancer is still one of the prevalent leading causes of cancer-related deaths worldwide. The high mortality rate is mainly due to late-stage diagnosis, which has a very poor prognosis (five-year survival rates are as little as 3-10%). By contrast, early stage gastric cancer is highly curable with five-year survival rates exceeding 90%. Early detection is therefore the single most important factor influencing the outcome for gastric cancer patients. However, there are currently no biomarkers of acceptable sensitivity and specificity to detect early stage gastric cancer. Gastric infection with Helicobacter pylori (H. pylori) seems to be a risk factor for gastric cancer. Epidemiological studies have shown that patients that test serum positive to H. pylori infection are associated with a three- to six-fold increase in the risk of gastric cancer, findings that are compatible with pathological links between H. pylori-associated gastritis, pre-cancerous lesions, and subsequent cancer of the stomach. In a previous study, moving from genomic to proteomic investigation, we have identified a protein, gastrokine 1 (GKN1), a stomach-secreted protein previously named AMP-18 (18kDa Antrum Mucosa Protein) that was highly expressed in normal tissues and significantly down-regulated in H. pylori positive patients with respect to H. pylori negative subjects. In addition, we have also found that GKN1 is normally expressed in gastric mucosa but not in primary tumours, both at the transcriptional and translational levels. On the basis of these findings, we propose that GKN1 can be used as a new molecular marker that could be useful to predict early cell transformation and might be a potential novel target for gastric cancer therapeutics. Moreover, we have also found that recombinant GKN1 affect cancer cell growth and that the transient expression of GKN1 in human gastric cancer also inhibits cell growth and induces apoptosis, thus suggesting the importance of GKN1 in preventing cancer development in gastric tissues. Finally, we hypothesize that GKN1 might act as a tumor suppressor and thus foresee its importance as an antitumor drug
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
Role of human GKN1 on APP processing in gastric cancer
No full textGastrokine 1 (GKN1) is highly expressed in gastric tissue and is secreted into the stomach but is not expressed in gastric cancer. GKN1 belongs to the BRICHOS domain family and plays a major role in maintaining gastric mucosa integrity. We previously demonstrated that a recombinant human GKN1 protein was able to interact with the amyloid precursor protein (APP) and was endowed with an anti-amyloidogenic property because it inhibited polymerization of the Aβ(1-40) peptide released from APP upon its partial hydrolysis. Here, we report that GKN1 can act as a physiological suppressor of Aβ production in gastric cancer cells. GKN1 blocked the access of γ-secretase to APP, thereby facilitating the cleavage of APP by α- and β-secretases. GKN1 directly interacted with APP C-terminal fragments, C83 and C99. In addition, it did not affect γ-secretase activity in gastric cancer cells because it did not alter Notch1 processing. GKN1-mediated inhibition of APP processing might represent a new approach for the prevention and therapy of Alzheimer's disease (AD)
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