[Current treatment concepts for trauma-related cardiac arrest : Focal points, differences and similarities]. / Aktuelle Behandlungskonzepte des "traumatischen Herz-Kreislauf-Stillstands" : Schwerpunkte, Unterschiede und Gemeinsamkeiten.

Trauma-related deaths are not only a relevant medical problem but also a socioeconomic one. The care of a polytraumatized patient is one of the less commonly occurring missions in the rescue and emergency medical services. The aim of this article is to compare the similarities and differences between different course concepts and guidelines in the treatment of trauma-related cardiac arrests (TCA) and to filter out the main focus of each concept. Because of the various approaches in the treatment of polytraumatized patients, there are decisive differences between trauma-related cardiac arrests and cardiac arrests from other causes.

[Inflammatory pseudotumours of the liver associated with Crohn's disease: a possible pitfall in contrast-enhanced ultrasound]. / Inflammatorische Pseudotumoren der Leber bei Morbus Crohn: ein möglicher Pitfall bei der Echokontrast-Sonografie.

Pseudotumours of the liver are rare entities, which cannot be differentiated from malignant liver lesions by contrast-enhanced ultrasound (CEUS) or radiological imaging. We report of a 22-year-old man with persistant abdominal pain and fever after appendectomy. Fundamental ultrasound showed an inflammatory swelling of the terminal ileum, suspicious of Crohn's disease as well as two solid liver lesions and left portal vein thrombosis. The enhancement patterns of both liver tumors on CEUS showed inhomogeneous isoenhancement during the arterial and portal phases and hypoenhancement during the late phase, mimiking malignant lesions. Ultrasound-guided biopsy, histology and follow-up, however, confirmed the diagnosis of hepatic inflammatory pseudotumour (IPT). When diagnosing a pseudotumour of the liver, the rare coincidence with chronic inflammatory bowel disease should be considered.

Downregulation of beta2-microglobulin in human cord blood somatic stem cells after transplantation into livers of SCID-mice: an escape mechanism of stem cells?

Adherently growing, non-hematopoietic somatic stem cells isolated from human cord blood were stained with the fluorescent dye PKH26 and transplanted into livers of SCID-mice to examine a possible cell fate transition. Already 7 days after transplantation stem cells were well integrated into the liver tissue. Human albumin that was not expressed by the stem cells before transplantation was detectable in the host's livers after injection of cord blood stem cells. Human alpha1-antitrypsin was detectable in stem cells already before transplantation and remained positive in the mouse liver. The most interesting observation in this study was the downregulation of human beta2-microglobulin (beta2M) in the stem cells after transplantation: beta2M is expressed constitutively in our cord blood stem cells. However, beta2M was no longer detectable by RT-PCR in all tissues where human albumin and alpha1-antitrypsin were expressed after stem cell transplantation. beta2M is known to participate as an integral part of the major histocompatibility complex. Absence of beta2M makes the residual heavy chain inactive as an antigen. Thus, downregulation of beta2M may represent an escape mechanism from killer-T cells and may be a molecular mechanism explaining the recently described "immunological blindness" [37] of stem cells. In contrast to the results obtained after direct injection of stem cells as a suspension, no consistent downregulation of beta2M was observed after transplantation of stem cells encapsulated in alginate beads to generate a compartment where stem cells are protected from the host's natural killer cells. No expression of human genes was observed after transplantation of human cord blood derived mononuclear cells (MNC) that were used as a negative control. In conclusion, we have shown that human cord blood somatic stem cells survive and are reprogrammed after transplantation into mouse livers, although a complete transdifferentiation to hepatocytes did not occur within 7 days, since some marker genes (GATA4 and alpha-fetoprotein) were still negative. Switching off expression of beta2M may be part of an intriguing and novel mechanism explaining why stem cells escape the host's immune system.