Progress in the treatment of gastroenterologic diseases in advanced age

Therapeutic advances in gastroenterology benefit patients of all ages, although the elderly ones receive more benefits than others. The latter is especially true for operative endoscopy where, in some cases, otherwise high-risk patients can be spared an operation. Peptic stenosis, which is common in elderly patients as a result of reflux oesophagitis, can be treated by bougienage. Bleeding from gastric and duodenal ulcers can cause problems in the elderly. In most cases endoscopic treatment by electro- or laser coagulation, or by sclerotherapy can avoid the need for surgery, or at least the conversion of an emergency operation into an elective one with a better prognosis is possible. Adenomata in the colon are common causes of chronic blood loss and can become malignant. They should be removed endoscopically. Another typical age-dependent finding, which can be treated by electro- or laser coagulation in the colon are angiodysplasia, which can be the origin of massive haemorrhage. It is now becoming accepted that in an elderly patient, stones in the common bile duct should be managed by endoscopic sphincterotomy and gallstone removal. This approach is safer and quicker than conventional surgery. The practice of endoscopic drainage by insertion of a prosthesis in cases of malignant obstructive jaundice is although increasing in older patients.     

Complications after meniscal repair with bioabsorbable arrows: two cases and analysis of literature

Biodegradable implants were introduced in the middle 1990s as a new technique for the arthroscopic treatment of reparable meniscal tears. We have used these implants since 1999 and present two cases of failure of biodegradable meniscal repair implants. One foreign-body reaction with granuloma and one fresh meniscus tear after renewed trauma in the case of receding meniscus arrows with a chondral lesion. We also performed a review of the literature with the Medline database. Meniscus refixation with bioabsorbable arrows is considered reliable but shows various other complications that must be borne in mind.     

A combined DNA-microarray and mechanism-specific toxicity approach with zebrafish embryos to investigate the pollution of river sediments

The zebrafish embryo has repeatedly proved to be a useful model for the analysis of effects by environmental toxicants. This proof-of-concept study was performed to investigate if an approach combining mechanism-specific bioassays with microarray techniques can obtain more in-depth insights into the ecotoxicity of complex pollutant mixtures as present, e.g., in sediment extracts. For this end, altered gene expression was compared to data from established bioassays as well as to results from chemical analysis. Mechanism-specific biotests indicated a defined hazard potential of the sediment extracts, and microarray analysis revealed several classes of significantly regulated genes which could be related to the hazard potential. Results indicate that potential classes of contaminants can be assigned to sediment extracts by both classical biomarker genes and corresponding expression profile analyses of known substances. However, it is difficult to distinguish between specific responses and more universal detoxification of the organism.     

Differential host determinants contribute to the pathogenesis of 2009 pandemic H1N1 and human H5N1 influenza A viruses in experimental mouse models

Influenza viruses are responsible for high morbidities in humans and may, eventually, cause pandemics. Herein, we compared the pathogenesis and host innate immune responses of a seasonal H1N1, two 2009 pandemic H1N1, and a human H5N1 influenza virus in experimental BALB/c and C57BL/6J mouse models. We found that both 2009 pandemic H1N1 isolates studied (A/Hamburg/05/09 and A/Hamburg/NY1580/09) were low pathogenic in BALB/c mice [log mouse lethal dose 50 (MLD(50)) >6 plaque-forming units (PFU)] but displayed remarkable differences in virulence in C57BL/6J mice. A/Hamburg/NY1580/09 was more virulent (logMLD(50) = 3.5 PFU) than A/Hamburg/05/09 (logMLD(50) = 5.2 PFU) in C57BL/6J mice. In contrast, the H5N1 influenza virus was more virulent in BALB/c mice (logMLD(50) = 0.3 PFU) than in C57BL/6J mice (logMLD(50) = 1.8 PFU). Seasonal H1N1 influenza revealed marginal pathogenicity in BALB/c or C57BL/6J mice (logMLD(50) >6 PFU). Enhanced susceptibility of C57BL/6J mice to pandemic H1N1 correlated with a depressed cytokine response. In contrast, enhanced H5N1 virulence in BALB/c mice correlated with an elevated proinflammatory cytokine response. These findings highlight that host determinants responsible for the pathogenesis of 2009 pandemic H1N1 influenza viruses are different from those contributing to H5N1 pathogenesis. Our results show, for the first time to our knowledge, that the C57BL/6J mouse strain is more appropriate for the evaluation and identification of intrinsic pathogenicity markers of 2009 pandemic H1N1 influenza viruses that are "masked" in BALB/c mice.