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The approach to limit therapy in very old intensive care unit patients (VIPs) significantly differs between regions. The focus of this multicenter analysis is to illuminate, whether the Clinical Frailty Scale (CFS) is a suitable tool for risk stratification in VIPs admitted to intensive care units (ICUs) in Germany. Furthermore, this investigation elucidates the impact of therapeutic limitation on the length of stay and mortality in this setting.

Abstract

We have examined the chromatin structure around and upstream of the transcriptional start site of the human α2(I) collagen (COL1A2) gene. Four strong DNase I-hypersensitive sites (HS2–5) were only detected in fibroblasts, and a weaker one (HS1) was identified in type I collagen-negative cells. Another hypersensitive site potentially involved in COL1A2 silencing was found in intron 1 (HS(In)). HS1 and HS2 were mapped within conserved promoter sequences and at locations comparable to the mouse gene. HS3, HS4, and HS5 were likewise mapped ∼20 kilobases upstream of COL1A2 at about the same position as the mouse far-upstream enhancer and within a remarkably homologous genomic segment. DNase I footprinting identified twelve areas of nuclease protection in the far-upstream region (FU1–12) and within stretches nearly identical to the mouse sequence. The region containing HS3–5 was found to confer high and tissue-specific expression in transgenic mice to the otherwise minimally active COL1A2 promoter. Characterization of the human element documented functional differences with the mouse counterpart. Enhancer activity substantially decreased without the segment containing FU1–7 and HS5, and inclusion of AluI repeats located 3′ of HS3 augmented position-independent expression of the transgene. Hence, subtle differences may characterize the regulation of mammalian α2(I) collagen genes by evolutionarily conserved sequences.

While the natural intact protein does not possess any transactivator function, C-terminal truncation of the middle hepatitis B surface (MHBs) protein yields a novel transactivator function. We have previously found that the truncated transactivator protein, MHBst167, is not secreted but retained within the secretory pathway. Here, we provide evidence that when full-length MHBs is coexpressed with the truncated MHBst167 protein, the secretion of the full-length protein is inhibited and both proteins accumulate within the cell. We further show that MHBs, forcibly retained in the cell by C-terminal fusion to the endoplasmic reticulum retention signal KDEL (MHBsKDEL), mimics the effects of MHBst167 in enhancing the nuclear-binding activity of transcription factors NFĸB and AP-1, and activation of NFĸB- and AP-1-dependent transcription of reporter genes. As is the case for MHBst167, MHBsKDEL-dependent activation of NFĸB is inhibited by the antioxidant N-acetyl-L-cysteine indicating the involvement of reactive oxygen intermediates and suggesting a similar mechanism of activation. This study suggests that the intracellular retention and accumulation of the normally secreted MHBs leads to oxidative stress and activation of transcription. This may be an important but not exclusive mechanism in hepatocarcinogenesis.

Hepatitis B infection is associated with an increased risk of hepatocellular carcinoma development. Hepatitis B proteins, such as the hepatitis B x protein, the large hepatitis B surface protein, or truncated middle hepatitis B surface proteins, regulate transcription of many candidate genes for liver carcinogenesis by trans-mechanisms. They also alter mechanisms of apoptosis and interfere with nucleotide excision repair of damaged DNA. Together with an influence on cellular signaling, these mechanisms may favor the cell’s clonal expansion.

Hepatitis B infection is strongly linked epidemiologically to hepatocellular carcinoma development. This article reviews the molecular mechanisms by which hepatitis B encoded proteins such as hepatitis B x and hepatitis B surface transactivators may interact with gene transcription, tumor suppression, apoptosis, and signalling pathways of the liver cell with the possible consequence of tumor induction. Data on the interaction between hepatitis B proteins and cellular processes are often conflicting indicating a non-specific simultaneous interaction with antagonistic cellular processes that result in the formation of escape mutants that are not subject to these selective pressures.

Olanzapine is a second-generation antipsychotic drug which is generally considered safe with well therapeutic antipsychotic effects. We describe a patient suffering from bilateral intracerebral hemorrhage after severe olanzapine intoxication without underlying thrombocytopenia, arterial hypertension, or vascular malformation as cause of intracerebral hemorrhage. This raises the possibility of a direct side effect of high-dose olanzapine intake. So far, intracranial hemorrhage after olanzapine intoxication in such constellation has not been reported before. Given the high number of its prescription rates, our finding of intracranial hemorrhage after olanzapine intoxication is of high clinical relevance.