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Mechanical blocking of the columnar front during the columnar to equiaxed transition (CET) is studied by quantitatively comparing the CET positions obtained with one stochastic model and two deterministic models for the unidirectional solidification of an Al-7 (wt pct) Si alloy. One of the deterministic models is based on the solutal blocking of the columnar front, whereas the other model is based on the mechanical blocking. The solutal-blocking model and the mechanical-blocking model with the traditional blocking fraction of 0.49 give columnar zones larger than those predicted with the stochastic model. When a blocking fraction of 0.2 is adopted, however, the agreement is very good for a range of nucleation undercoolings and number density of equiaxed grains. Therefore, changing the mechanical-blocking fraction in deterministic models from 0.49 to 0.2 seems to model more accurately the mechanical-blocking process that can lead to the CET. [ABSTRACT FROM AUTHOR]

Background: Bismuth quadruple (BQT) and non-bismuth quadruple (N-BQT) therapies are the recommended first-line treatments for Helicobacter (H.) pylori infection., Objective: To compare the efficacy of BQT and N-BQT in clinical practice in an area with high clarithromycin resistance, choosing the regimen on the basis of previous exposure to clarithromycin., Methods: A total of 404 consecutive H pylori-positive, naïve patients were enrolled. A total of 203 patients without previous exposure to clarithromycin received N-BQT, 100 patients for 10 days and 103 for 14 days, whereas 201 with previous exposure to clarithromycin received 10-day BQT. Efficacy and treatment-related adverse events were assessed., Results and Conclusions: Eradication rates by intention-to-treat analysis were 88.2% for N-BQT and 91.5% for BQT (P = .26); per-protocol analysis eradication rates were 91.2% and 95.8% for N-BQT and BQT, respectively (P = .07). Eradication rates were significantly higher with 14-day than 10-day CT (P < .003). Almost all patients had a good compliance with both N-BQT (95.6%) and BQT (95%). Adverse events occurred in 24.1% and 26.9% (P = .53) of patients in the N-BQT and BQT group, respectively. In conclusion, clarithromycin-containing non-bismuth or bismuth quadruple therapy, based on the knowledge of previous clarithromycin exposure, is effective and safe even in an area of high prevalence of clarithromycin-resistant H pylori strains., (© 2020 John Wiley & Sons Ltd.)

Background: Urotensin II (U-II) is a vasoactive peptide that interacts with a specific receptor named UTR. Recently, our group has demonstrated increased UTR expression in both human colon adenocarcinoma cell lines and adenomatous polyps, as well as in colon carcinoma samples if compared to healthy colon samples of the same patients. We also showed that an UTR agonist induced an increase in colon adenocarcinoma cell growth in vitro, whereas the UTR block with a specific antagonist caused an inhibition of their growth and an inhibition of about 50% of both motility and cell invasion. Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) associated with an increased baseline risk for colon cancer compared with the general population, and this risk is mostly attributed to chronic inflammation and immune dysregulation. This risk increases along with the duration of the disease, as demonstrated by many studies. There are no UTR expression data related to UC, and we therefore evaluated UTR expression in ill colon biopsies and in healthy colon ones of patients with UC and colon biopsies of healthy patients., Methods: We enrolled, prior to informed consent, 11 patients (5 males and 6 females, age range 29-75 years, median age 52 years) with first UC diagnosis compared to 11 healthy controls (6 males and 5 females, age range 30-78 years, median age 55 years). We have therefore sampled inflammatory and healthy tissue in UC patients. We have also taken colic tissue samples in healthy subjects. Evaluation of receptor expression was performed by reverse transcription-polymerase chain reaction (RT-PCR), Western Blot analysis. The ANOVA Test (P<0.05) was used for statistical analysis., Results: We found: 1) increased expression of UTR in 11/11 UC patients with ill mucosa biopsies compared to healthy controls in RT-PCR and in Western Blot analysis; 2) increased UTR expression in 11/11 UC patients with ill colon biopsies compared to the results obtained from healthy colon biopsies of the same patients both in RT-PCR and in Western Blot analysis; 3) increased UTR expression in 9/11 UC patients healthy colon biopsy specimens compared to healthy controls., Conclusions: UTR could be considered as an inflammatory UC disease marker because its expression is greater in the mucosa of ill colon than in the healthy colon of the same patients and compared to healthy controls.

Background: Anaemia (AN) is frequently associated with inflammatory bowel diseases (IBD) and can negatively influence the quality of life of patients., Aim: To evaluate the prevalence and causes of AN in IBD., Methods: We prospectively performed a one-year multicentre observational study including all IBD cases attending six Units. We also investigated patients' main serological parameters., Results: The study population included 965 IBD patients (582 CD; 383 UC), of whom 142 were in-patients and 823 out-patients. AN was diagnosed in 134 out of 965 IBD patients (14%). No significant difference in AN prevalence was observed between CD and UC. The prevalence of AN was higher in the hospitalized IBD (26% in- vs. 11.7% out-patients; p<0.01; OR 2.2) and in active disease (CD: 34% active vs. 16% inactive; p<0.01; OR 2.1 - UC: 26% active vs. 19% inactive; p=0.03; OR 1.3). Iron deficiency was present in 72 patients (53.7%), AN of chronic diseases in 12 (8.2%), mixed type AN in 11 (8.2%), thalassemia in 9 (6.7%), and macrocytic AN in 8 (5.9%)., Conclusions: In Southern Italy, AN is common in IBD and is more frequent in active disease and hospitalized patients. Iron deficiency still remains the major cause of AN in IBD., (Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Background: Aim was to evaluate the efficacy and tolerability of a moxifloxacin-containing second-line triple regimen in patients whose previous Helicobacter pylori eradication treatment failed., Methods: Prospective multicentre study including patients in whom a triple therapy or a non-bismuth-quadruple-therapy failed. Moxifloxacin (400mg qd), amoxicillin (1g bid), and esomeprazole (40 mg bid) were prescribed for 14 days. Eradication was confirmed by (13)C-urea-breath-test. Compliance was determined through questioning and recovery of empty medication envelopes., Results: 250 patients were consecutively included (mean age 48 ± 15 years, 11% with ulcer). Previous (failed) therapy included: standard triple (n = 179), sequential (n = 27), and concomitant (n = 44); 97% of patients took all medications, 4 were lost to follow-up. Intention-to-treat and per-protocol eradication rates were 82.4% (95% CI, 77-87%) and 85.7% (95% CI, 81-90%). Cure rates were similar independently of diagnosis (ulcer, 77%; dyspepsia, 82%) and previous treatment (standard triple, 83%; sequential, 89%; concomitant, 77%). At multivariate analysis, only age was associated with eradication (OR = 0.957; 95% CI, 0.933-0.981). Adverse events were reported in 25.2% of patients: diarrhoea (9.6%), abdominal pain (9.6%), and nausea (9.2%)., Conclusion: 14-day moxifloxacin-containing triple therapy is an effective and safe second-line strategy in patients whose previous standard triple therapy or non-bismuth quadruple (sequential or concomitant) therapy has failed, providing a simple alternative to bismuth quadruple regimen., (Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Objectives: From an Italian Registry of patients with upper gastrointestinal hemorrhage (UGIH), we assessed the clinical outcomes and explored the roles of clinical, endoscopic, and therapeutic factors on 30-day mortality in a real life setting., Methods: Prospective analysis of consecutive patients endoscoped for UGIH at 23 community and tertiary care institutions from 2003 to 2004. Covariates and outcomes were defined a priori and 30-day follow-up obtained. Logistic regression analysis identified predictors of mortality., Results: One thousand and twenty patients were included. A total of 46 patients died for an overall 4.5% mortality rate. In all, 85% of deaths were associated with one or more major comorbidity. Sixteen of 46 patients (35%) died within the first 24 h of the onset of bleeding. Of these, eight had been categorized as ASA class 1 or 2 and none of them was operated upon, despite a failure of endoscopic intention to treatment in four. Regression analysis showed advanced age, presence of severe comorbidity, low hemoglobin levels at presentation, and worsening health status as the only independent predictors of 30-day mortality (P < 0.001). The acute use of a PPI exerted a protective effect (OR 0.23, 95% CI 0.09-0.73). Recurrent bleeding was low (3.2%). Rebleeders accounted for only 11% of the total patients deceased (OR 3.27, 95% CI 1.5-11.2)., Conclusions: These results indicate that 30-day mortality for nonvariceal bleeding is low. Deaths occurred predominantly in elderly patients with severe comorbidities or those with failure of endoscopic intention to treatment.