Assessment of radiofrequency ablation technique in development of aortic valve stenosis in rabbits

Purpose: To develop a minimally invasive and reproducible model of aortic stenosis in rabbits using radiofrequency ablation technique (RFA). Material and methods: Eleven rabbits were studied. A radiofrequency ablation catheter was introduced via the femoral artery and advanced to the aortic valve area under fluoroscopic control. In three rabbits radiofrequency energies, at 5 W, 10 W and 15 W respectively, were applied thrice for 90 sec. In eight rabbits, energy of 15 W was applied for the same time periods. The velocity of the blood through the aortic valve was determined by color Doppler ultrasound immediately before and after ablation and after six weeks. After six weeks the rabbits were sacrificed and the aortic valve was examined macroscopically. Results: Peak systolic velocity (PSV) was similar at the time of ablation and after six weeks in eight of the nine surviving rabbits, and had increased from 1.1 to 1.75 m/s in one rabbit. Two rabbits developed aortic insufficiencies visualized by color Doppler. No macroscopic changes were seen at the aortic valve area 6 weeks after ablation. Conclusion: In the current study we did not succeed in inducing aortic valve damage/fibrosis using different RFA energies. Inadequate RFA power or inappropriate positioning of the RFA catheter could be limitations of our study

Classification of tumours

Tumours are classified according to the most differentiated cells with the exception of carcinomas where a few tumour cells show neuroendocrine differentiation. In this case these cells are regarded as redifferentiated tumour cells, and the tumour is not classified as neuroendocrine. However, it is now clear that normal neuroendocrine cells can divide, and that continuous stimulation of such cells results in tumour formation, which during time becomes increasingly malignant. To understand tumourigenesis, it is of utmost importance to recognize the cell of origin of the tumour since knowledge of the growth regulation of that cell may give information about development and thus possible prevention and prophylaxis of the tumour. It may also have implications for the treatment. The successful treatment of gastrointestinal stromal tumours by a tyrosine kinase inhibitor is an example of the importance of a correct cellular classification of a tumour. In the future tumours should not just be classified as for instance adenocarcinomas of an organ, but more precisely as a carcinoma originating from a certain cell type of that organ

Proton pump inhibitors and risk of gastric cancer: a population-based cohort study

Proton pump inhibitor (PPI) use leads to hypergastrinaemia, which has been associated with gastrointestinal neoplasia. We evaluated the association between PPI use and risk of gastric cancer using population-based health-care registers in North Jutland, Denmark, during 1990–2003. We compared incidence rates among new users of PPI (n=18 790) or histamine-2-antagonists (H2RAs) (n=17 478) and non-users of either drug. Poisson regression analysis was used to estimate incidence rate ratios (IRRs) adjusted for multiple confounders. We incorporated a 1-year lag time to address potential reverse causation. We identified 109 gastric cancer cases among PPI users and 52 cases among H2RA users. After incorporating the 1-year lag time, we observed IRRs for gastric cancer of 1.2 (95% CI: 0.8–2.0) among PPI users and 1.2 (95% CI: 0.8–1.8) among H2RA users compared with non-users. These estimates are in contrast to significant overall IRRs of 9.0 and 2.8, respectively, without the lag time. In lag time analyses, increased IRRs were observed among PPI users with the largest number of prescriptions or the longest follow-up compared with H2RA users or non-users. Although our results point to a major influence of reverse causation and confounding by indication on the association between PPI use and gastric cancer incidence, the finding of increased incidence among PPI users with most prescriptions and longest follow-up warrants further investigation

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

The epidemiology of renal replacement therapy in two different parts of the worldThe Latin American Dialysis and Transplant Registry versus the European Renal Association-European Dialysis and Transplant Association Registry

Publisher Copyright: © 2018 Pan American Health Organization. All rights reserved.Objective: To compare the epidemiology of renal replacement therapy (RRT) for end-stage renal disease (ESRD) in Latin America and Europe, as well as to study differences in macro-economic indicators, demographic and clinical patient characteristics, mortality rates, and causes of death between these two populations. Methods: We used data from 20 Latin American and 49 European national and subnational renal registries that had provided data to the Latin American Dialysis and Renal Transplant Registry (RLADTR) and the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry, respectively. The incidence and prevalence of RRT in 2013 were calculated per million population (pmp), overall and by subcategories of age, sex, primary renal disease, and treatment modality. The correlation between gross domestic product and the prevalence of RRT was analyzed using linear regression. Trends in the prevalence of RRT between 2004 and 2013 were assessed using Joinpoint regression analysis. Results: In 2013, the overall incidence at day 91 after the onset of RRT was 181 pmp for Latin American countries and 130 pmp for European countries. The overall prevalence was 660 pmp for Latin America and 782 pmp for Europe. In the Latin American countries, the annual increase in the prevalence averaged 4.0% (95% confdence interval (CI): 2.5%-5.6%) from 2004 to 2013, while the European countries showed an average annual increase of 2.2% (95% CI: 2.0%-2.4%) for the same time period. The crude mortality rate was higher in Latin America than in Europe (112 versus 100 deaths per 1 000 patient-years), and cardiovascular disease was the main cause of death in both of those regions. Conclusions. There are considerable differences between Latin America and Europe in the epidemiology of RRT for ESRD. Further research is needed to explore the reasons for these differences.Peer reviewe