1,720,980 research outputs found
Nickel-Related Intestinal Mucositis in IBS-Like Patients: Laser Doppler Perfusion Imaging and Oral Mucosa Patch Test in Use
No full textNickel (Ni) is often the trigger of irritable bowel syndrome (IBS)-like gastrointestinal disorders: its ingestion may cause allergic contact mucositis, identifiable by means of oral mucosa patch test (omPT). OmPT effectiveness has been proven, but it is still an operator-dependent method. Laser Doppler perfusion imaging (LDPI) was tested to support omPT in Ni allergic contact mucositis diagnosis. Group A: 22 patients with intestinal/systemic symptoms related to the ingestion of Ni-containing foods. Group B: 12 asymptomatic volunteers. Ni-related symptoms and their severity were tested by a questionnaire. All patients underwent Ni omPT with clinical evaluation at baseline (T0), after 30 min (T1), after 2 h (T2), and after 24-48 h (T3). LDPI was performed to evaluate the mean mucosal perfusion at T0, T1, and T2. Statistical analysis was performed by ANOVA test and Bonferroni multiple-comparison test. All 22 Ni-sensitive patients (group A) presented oral mucosa hyperemia and/or edema at T2. Eight out of the same 22 patients presented a local delayed vesicular reaction at T3 (group A1), unlike the remaining 14 out of 22 patients (group A2). All 12 patients belonging to control group B did not show any alteration. The mean mucosal perfusion calculated with LDPI showed an increase in both subgroups A1 and A2. In group B, no significant perfusion variations were observed. LDPI may support omPT for diagnostic purposes in Ni allergic contact mucositis. This also applies to symptomatic Ni-sensitive patients without aphthous stomatitis after 24-48 h from omPT and that could risk to miss the diagnosis
The Spigelman Staging System and the Risk of Duodenal and Papillary Cancer in Familial Adenomatous Polyposis: A Systematic Review and Meta-Analysis
No full textINTRODUCTION: Individuals with familial adenomatous polyposis (FAP) have an almost 20% lifetime risk of duodenal adenocarcinoma, currently the leading cause of death in FAP. The Spigelman staging system provides guidance on the surveillance intervals and timing of prophylactic surgery. Still, its accuracy in predicting duodenal and papillary cancer development has not been systematically evaluated. We investigated the sensitivity and cancer risk of the Spigelman stages. METHODS: We performed a systematic review on PubMed, MEDLINE, EMBASE, and Cochrane and used a random-effects model to pool effect sizes. RESULTS: After removing duplicate entries, we screened 1,170 records and included 27 studies for quantitative analysis. Once duodenal polyposis reaches Spigelman stage IV, the risk of duodenal and papillary cancers increased to 25% (95% confidence interval [CI] 12%-45%). However, the sensitivity of Spigelman stage IV for these cancers was low (51%, 95% CI 42%-60%), especially for papillary adenocarcinoma (39%, 95% CI 16%-68%). We investigated the reasons behind these low values and observed that duodenal cancer risk factors included polyps >10 mm, polyp count >20, and polyps with high-grade dysplasia. Risk factors associated with papillary cancer included a papilla with high-grade dysplasia or >10 mm. The evidence on other risk factors was inconclusive. DISCUSSION: The current Spigelman staging system had a low sensitivity for duodenal and papillary adenocarcinomas. Two Spigelman variables (duodenal villous histology and polyp count) and the lack of papilla-specific variables likely contributed to the low sensitivity values for duodenal and papillary cancers, respectively. While clinicians may be familiar with its current form, there is an urgent need to update it.INTRODUCTION: Individuals with familial adenomatous polyposis (FAP) have an almost 20% lifetime risk of duodenal adenocarcinoma, currently the leading cause of death in FAP. The Spigelman staging system provides guidance on the surveillance intervals and timing of prophylactic surgery. Still, its accuracy in predicting duodenal and papillary cancer development has not been systematically evaluated. We investigated the sensitivity and cancer risk of the Spigelman stages. METHODS: We performed a systematic review on PubMed, MEDLINE, EMBASE, and Cochrane and used a random-effects model to pool effect sizes. RESULTS: After removing duplicate entries, we screened 1,170 records and included 27 studies for quantitative analysis. Once duodenal polyposis reaches Spigelman stage IV, the risk of duodenal and papillary cancers increased to 25% (95% confidence interval [CI] 12%-45%). However, the sensitivity of Spigelman stage IV for these cancers was low (51%, 95% CI 42%-60%), especially for papillary adenocarcinoma (39%, 95% CI 16%-68%). We investigated the reasons behind these low values and observed that duodenal cancer risk factors included polyps >10 mm, polyp count >20, and polyps with high-grade dysplasia. Risk factors associated with papillary cancer included a papilla with high-grade dysplasia or >10 mm. The evidence on other risk factors was inconclusive. DISCUSSION: The current Spigelman staging system had a low sensitivity for duodenal and papillary adenocarcinomas. Two Spigelman variables (duodenal villous histology and polyp count) and the lack of papilla-specific variables likely contributed to the low sensitivity values for duodenal and papillary cancers, respectively. While clinicians may be familiar with its current form, there is an urgent need to update it
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
Association of endogenous and exogenous factors with early-onset colorectal cancer: germline mutations, epigenetic modifications, diet and lifestyle habits
Full text linkThe incidence of early-onset colorectal cancer (eoCRC), defined as colorectal cancer occurring in young adults under the age of 50, is increasing globally. However, knowledge of the etiological factors and characteristics of CRC in young adults is far from complete.
Estimating the impact of pathogenic variants (PVs) in eoCRC predisposition remains an active field of research. Therefore the 1st aim was to evaluate the associations of germline PVs and family history of CRC with eoCRC. A total of 105 eoCRCs were enrolled (mean age at diagnosis of 41.2 ± 6.7 years; 48.6% females, 51.4% males) for genetic testing through next-generation sequencing and multiplex ligation-dependent probe amplification. 20% of eoCRC carried a germline PV of genes known to be associated with CRC, of which 12.4% of mismatch repair genes, 2.9% of BRCA1-2, 3.8% of MUTYH, 0.9% of ATM, 0.9% of SDHAF2. One patient exhibited mosaicism of PVs in MSH2/MUTYH genes. 71.4% of eoCRCs didn’t have a family history of CRC; 19% of eoCRCs reported having a first degree relative (FDR) with CRC and 12.4% had a second degree relative (SDR) with CRC; three patients had both a FDR and SDR with CRC and were all Lynch patients. When comparing mutated-eoCRCs with non-mutated eoCRCs, no statistically significant differences were found in terms of age at diagnosis or sex, location of CRC, presence of FDR with CRC. Mutated eoCRC differed significantly from non-mutated eoCRCs in terms of SDRs with CRC (p < 0.001).
In conclusion, 20% of eoCRCs are caused by germline pathogenic variants (PV) and a negative family history does not exclude hereditary cancer syndromes. Therefore, thorough family history should be routinely collected for all individuals with eoCRC and all patients with eoCRC should be offered multi-gene panel germline genetic testing. Identification of LS individuals as well as carriers of other relevant germline PVs (e.g. BRCA2, MUTYH) will allow at-risk individuals to take personalised preventive measures for both proband and relatives.
Questionable eoCRCs' exogenous risk factors are represented by diet and lifestyle, even though a still scant literature is available to date. Moreover, most studies are small, heterogeneous, focused exclusively on peculiar dietary and drinking habits of single countries without analyzing cooking, processing, and storage techniques. Therefore, our 2nd aims were to (i) develop a unique and shared semi-quantitative food frequency questionnaire (SQFFQ) able to accurately describe dietary and drinking habits of eoCRCs and healthy controls of different countries at global level that will be involved in the future DEMETRA study (international case-control study evaluating the association of dietary, lifestyle and anthropometric factors with eoCRC of countries with different eoCRC incidence); (ii) validate the SQFFQ, making data obtained from different dietary questionnaires comparable. We designed an ad-hoc, shared, online SQFFQ to investigate the usual consumption of 329 foods, grouped into 61 food groups, over the past year. In addition to frequency of consumption, the tool investigates the portions habitually consumed using validated photographs, household measures, and standard units, as well as types of seasoning and methods of cooking. A special software was then developed to analyze responses and link them to food composition tables in order to provide a nutritional breakdown of individual and collective diets. The SQFFQ was then validated for repeatability by administering it twice, 3 weeks apart, to a sample of 30 young adults under 50 years (Internal Validation). To evaluate repeatability, the measurement error for each food group was estimated as the percentage change between the estimates of food consumption for the same individual. Afterwards, the agreement between the two measurements for each food group was measured with Cohen's kappa coefficient. Agreement levels, represented by the calculation of Cohen's kappa coefficient, were as follows: 12 food groups showed fair/sufficient agreement (Cohen's kappa 20-40), 23 foods exhibited good/moderate agreement (Cohen's kappa >40-60), and 22 food groups demonstrated high substantial agreement (Cohen's kappa >60). Therefore, the ad hoc designed SQFFQ provides a reasonably repeatable measure of dietary intake and can be used to assess the dietary and drinking habits of volunteers in this age group. Indeed, most staple foods in the Italian diet, including pasta, fruit, vegetables, legumes, eggs, meat, coffee, and tea, are well estimated by the SQFFQ. However, as yet described in literature, challenges persist in estimating the consumption of foods assumed sporadically (such as snacks) or in small quantities such as spices. Definitive conclusions will be drawn after the completion of the ongoing External validation, involving 100 volunteers from the same age group. In this phase, the SQFFQ will be validated against the gold standard, represented by a 4 days-food diary followed by a dietary recall. Once validation is complete, the international, multicenter, case-control study will start to evaluate the associations of diet, lifestyle and anthropometric factors with eoCRC comparing patients from countries with different incidence of eoCRC.
Epigenetic changes are crucial in the pathogenesis of CRC, representing the missing link between CRC, specific gene expression patterns and the absence of genetic alterations. One of the most important epigenetic modifications involved in carcinogenesis is represented by an altered expression of microRNAs (miRNAs). Distinct miRNAs could be differentially expressed in patients with recurrent vs. non-recurrent eoCRC and used as simple predictive biomarkers to select the optimal post-treatment surveillance regimen in managing patients with stage I-III eoCRC. Therefore, the 3rd aim was to identify candidate miRNAs that were differentially expressed in eoCRC patients with and without recurrence and define which patients could benefit most from more aggressive surveillance. We employed a five-layer approach for the development of a simple and clinically feasible test that may be translated into clinical practice. The first phase of the study (Discovery) consisted in the systematic interrogation and profiling of miRNA expression levels in 20 formalin-fixed paraffin-embedded (FFPE) samples of stage II-III eoCRCs that did (n 10) or did not (n 10) develop recurrence in five years following curative-intent surgery. In phase two (Assay development), we performed several bioinformatic analyses to identify the best candidate miRNAs that were differentially expressed in eoCRCs with and without recurrence and provided the highest discriminatory power between the two groups. At the end of phase two, we selected 10 best performing miRNAs and quantified their expression via qPCR. This third phase utilized 88 FFPE from a larger, independent training cohort of stage I-III eoCRC who received curative-intent surgery (24 recurrent and 63 non-recurrent eoCRCs). Because there is no unique and universally accepted normalized miRNA, we employed several bioinformatic approaches to rigorously establish the ideal candidate based on intra- and inter-group expression stability. In the Assay Training phase, we optimized and trained an advanced machine learning algorithm (XGBoost) to predict the development of eoCRC recurrence based on RT-qPCR data and performed several interrogations to the model to understand its functioning. The optimized XGBoost-based 9-miRNAs risk-assessment model demonstrated a high accuracy in predicting recurrence in stage I-III eoCRCs in the training cohort with an AUC value of 0.90 (95% CI 83-95%) with a Youden index of 64.9% (CI 95%, 55%-82%), an accuracy of 81.8% (77-93%), sensitivity 84.0% (65-96%), specificity 81.0% (72-98%). We then evaluated the survival characteristics of the XGB model and observed that our 9-miRNA model can discriminate effectively between recurrent and non-recurrent cases up to 20 years after surgical resection: patients predicted to be at a high risk of recurrence by the XGB model had a statistically significant cumulative hazard of disease recurrence than those classified as low-risk (p<0.001). Finally, we performed an independent validation of our assay in a distinct and ethnically different validation cohort of 69 FFPE of stage I-III eoCRCs who received curative-intent surgery for eoCRC (9 recurrent and 60 non-recurrent). The XGBoost-based risk-assessment model, incorporating 9-miRNAs, exhibited good accuracy in predicting recurrence among stage I-III eoCRCs in the validation cohort, achieving an AUC value of 0.77 (95% CI 67.0-87.0%), with a sensitivity of 100% (88-100%), specificity of 62.9% (55-82%), accuracy 66.7% (59.0-83.0%), and Youden index of 62.9% (54-73%). To truly gauge the effects that this assay would have in a real-world scenario, we performed several decision-curve analyses. We observed a net benefit of the surveillance based on our 9-miRNA signature compared to the clinical-based surveillance especially in stage I and II high risk eoCRC, representing the subgroups of patients that could benefit more from more aggressive post-treatment follow-up strategies. Therefore, if confirmed in prospective trials, this 9-miRNA signature could establish the fundamentals of personalized medicine
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
