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Background Coeliac disease is one of the most prevalent immune-mediated gastrointestinal disorders in children. Aim To review the incidence and prevalence of paediatric coeliac disease, and their trends, regionally across Europe, overall and according to age at diagnosis. Methods Systematic review and meta-analysis from January 1, 1950 to December 31, 2019, based on PubMed, CINAHL and the Cochrane Library, searches of grey literature and websites and hand searching of reference lists. A total of 127 eligible studies were included. Results The prevalence of previously undiagnosed coeliac disease from screening surveys (histology based) ranged from 0.10% to 3.03% (median = 0.70%), with a significantly increasing annual trend (P = 0.029). Prevalence since 2000 was significantly higher in northern Europe (1.60%) than in eastern (0.98%), southern (0.69%) and western (0.60%) Europe. Large increases in the incidence of diagnosed coeliac disease across Europe have reached 50 per 100 000 person-years in Scandinavia, Finland and Spain. The median age at diagnosis increased from 1.9 years before 1990 to 7.6 since 2000. Larger increases in incidence were found in older age groups than in infants and ages Paediatric coeliac disease incidence and prevalence have risen across Europe and appear highest in Scandinavia, Finland and Spain. The most recent evidence shows large increases in incidence in most regions, but stabilisation in some (notably Sweden and Finland). Sharp increases in the age at diagnosis may reflect increases in milder and asymptomatic cases diagnosed since reliable serology testing became widely used, through endomysial antibodies after 1990 and tissue transglutaminase antibodies around 2000.

The effect of perioperative blood transfusion on the recurrence of Crohn's disease is controversial. Various studies have suggested that perioperative blood transfusions reduce the risk of recurrence ; others have failed to find a protective effect. Since all the studies are based on relatively small numbers, we performed a pooled analysis. We contacted the senior authors of seven previously published studies and asked for the original data. Four authors provided their data. The pooled database included 622 patients with a primary and complete resection of macroscopic disease. Recurrence was defined as the need for repeat surgery for disease control. Kaplan-Meier life table analysis was performed. Of the study sample, 366 cases (59%) were female. Disease distribution was as follows : small bowel (47%), small/large bowel (35%), and large bowel only (18%). Three hundred thirty-one patients (53%) received blood in the perioperative period. Mean follow-up was 72.8 months. For the overall sample, the 5-year recurrence rates were 26.9% for the transfused group and 25.2% for the nontransfused (p = 0.456). When the data were stratified by age, gender, disease location, and length of resection, no difference in 5-year recurrence rates between transfused and nontransfused cases could be detected. In this pooled analysis of four retrospective studies on the effect of blood transfusions on the risk of recurrence in Crohn's disease, we were unable to document a protective effect.

The purpose of this study was to validate a new technique for measuring duodenogastric bile reflux in the human subject. A custom built cadmium telluride gamma detector (Radiation Monitoring Devices, Mass), small enough to be passed into the oesophagus and stomach, was developed and tested for sensitivity to 99Tcm and 75Se radioisotopes. When immersed in radiolabelled water, the detector was capable of measuring gamma radiation in quantities as low as 0.1 microCi (0.0037 MBq) per ml. Two patients (A and B) with endoscopically proven bile reflux, and three normal volunteers (C, D and E) underwent oesophageal manometry to map the position of the lower oesophageal sphincter (LOS). The gamma probe was passed via the nose, to a position in the gastric fundus, 5 cm below the LOS. Each subject was placed supine under a gamma camera (Siemens LFOV 37 ZLC head), centred on the epigastrium. A 4 mCi (148 MBq) dose of radiolabelled 99Tcm-HIDA was administered intravenously, and simultaneous internal/external scanning was performed for between 45 and 90 min. Internal gamma probe data was transferred by a screened cable to a Memolog 600 portable recorder, using a 5 s counting interval, and from the gamma camera to a Nodecrest Micas III computer, using a 15 s counting interval. Gamma camera counts from a region of interest over the fundus of the stomach were then correlated with counts from the internal probe using a linear regression analysis program on the Nodecrest. The internal gamma probe functioned well at body temperature in the acidic gastric environment. Radiolabelled bile refluxed into the stomach during HIDA scanning in three out of the five subjects (one patient and two normal volunteers). There was a strong correlation between internal and external gamma counts (A, r = +0.79; C, r = +0.53; E, r = +0.54; P greater than 0.01). In the other two cases, there was no bile reflux, but still a significant correlation between internal and external gamma counts (B, r = +0.89; D, r = +0.75; P greater than 0.01). The mean correlation coefficient for the series of five cases was +0.70. We conclude firstly that the newly developed internal gamma detector is capable of measuring the reflux of radiolabelled bile into the human stomach and, secondly, that bile reflux may occur in normal subjects as well as those with upper gastrointestinal pathology.

Određivanje parametara mehanike loma polimernih materijala pri dinamičkim opterećenjima moguće je provesti dinamičkim testom savijanja u tri točke. Nažalost, točnost metode dominantno ovisi o udarnim brzinama, a kod udarnih brzina većih od 1 m/s potrebno je uvažiti i dinamičke efekte poput inercijalnih sila i propagaciju valova naprezanja kroz geometriju ispitnog tijela. U radu je provedena numerička analiza koja je identificirala omjer kontaktnih krutosti između opterećujućeg trna, oslonaca i ispitnog tijela kao važan parametar na korekcijsku funkciju za lomnu žilavost K uslijed dinamičkih efekata.

U radu je opisana numerička metoda za predviđanje zaostalih naprezanja u polimernim materijalima sa izraženom temperaturom staklišta Tg. Zaostala naprezanja simulirana su sa toplinskim naprezanjima, dobivenim kao odziv materijala na „zaostalo“ temperaturno polje Tres. „Zaostalo“ temperaturno polje Tres uzima u obzir temperaturnu povijest materijala prilikom termičke obrade, a poglavito temperaturni gradijent u trenutku solidifikacije na Tg, po iznosu i po smjeru. Ovaj temperaturni gradijent je mjera trajne deformacije uslijed skrutnjavanja u materijalu. Specifičnosti numeričkog algoritma sa ortogonalnim linijama na solidifikacijske frontove kao i numeričke nestabilnosti oko „vruće“ linije detaljno su opisani u radu.