Background

Sorafenib is the current standard of care for patients with advanced hepatocellular carcinoma (aHCC) and has been shown to improve survival by about 3 months compared to placebo. However, survival varies widely from under three months to over two years. The aim of this study was to build a statistical model that allows personalised survival prediction following sorafenib treatment.

Methods

We had access to 1130 patients undergoing sorafenib treatment for aHCC as part of the control arm for two phase III randomised clinical trials (RCTs). A multivariable model was built that predicts survival based on baseline clinical features. The statistical approach permits both group-level risk stratification and individual-level survival prediction at any given time point. The model was calibrated, and its discrimination assessed through Harrell’s c-index and Royston-Sauerbrei’s R²_D.

Results

The variables influencing overall survival were vascular invasion, age, ECOG score, AFP, albumin, creatinine, AST, extra-hepatic spread and aetiology. The model-predicted survival very similar to that observed. The Harrell’s c-indices for training and validation sets were 0.72 and 0.70, respectively indicating good prediction.

Conclusions

Our model (‘PROSASH’) predicts patient survival using baseline clinical features. However, it will require further validation in a routine clinical practice setting.

Visual perception, and by implication underlying neural events, can become unstable when optical information specifying objects is ambiguous. Here we report that one striking form of instability—perceived three-dimensional structure-from-motion (SFM)—can be stabilized when an otherwise ambiguous object appears within a context implying frictional interactions with another rotating object; violations of physical conditions specifying friction disrupt stabilization. Evidently, information about frictional interaction is embedded within neural mechanisms specifying SFM.

A panel of human colonic adenocarcinoma cell lines was examined both for expression of mRNAs of the nitric oxide synthase (NOS) gene family and for evidence of enzymic activity based on citrulline and nitrite (NO2-) formation. Reverse transcription-polymerase chain reaction (RT-PCR), revealed that all lines (SW480, SW620, DLD-1 and WiDr) expressed mRNA for the Ca(2+)-dependent endothelial (e)NOS, while SW480 cells also expressed the Ca(2+)-dependent neuronal (n)NOS. The mRNA for the Ca(2+)-independent inducible (i)NOS was expressed both by cytokine-stimulated and by unstimulated SW480, SW620 and DLD-1 cells, but none was seen at any time in the WiDr cells. There was, however, little correlation between mRNA expression and enzymic activity based on citrulline and NO2- formation. Thus none of the cell lines exhibited measurable Ca(2+)-dependent NOS activity, while Ca(2+)-independent NOS activity was seen in all but the WiDr cells. Furthermore, DLD-1 cells generated citrulline with resultant NO2- formation only after stimulation with lipopolysaccharide (LPS) and/or cytokines, while SW480 and SW620 did so constitutively. Thus RT-PCR studies indicate that tumour cells of similar epithelial origin display a diverse pattern of NOS gene family expression, and parallel biochemical studies clearly indicate that such expression does not always result in measurable enzymic activity leading to the generation of NO.

Promising advances in nonviral gene transfer have been made as a result of the production of cationic liposomes formulated with synthetic cationic lipids (cytofectins) that are able to transfect cells. However few cationic liposome systems have been examined for their ability to transfect CNS cells. Building upon our earlier use of cationic liposomes formulated from 3β-[N-(N′,N′-dimethylaminoethane)carbamoyl] cholesterol (DC-Chol) and dioleoyl-L-α-phosphatidyl-ethanolamine (DOPE), we describe studies using two cationic viral peptides, μ (mu) and Vp1, as potential enhancers for cationic liposome-mediated transfection. Mu is derived from the condensed core of the adenovirus and was selected to be a powerful nucleic acid charge neutralising and condensing agent. Vp1 derives from the polyomavirus and harbours a classical nuclear localisation signal (NLS). Vp1 proved disappointing but lipopolyplex mixtures formulated from pCMVβ plasmid, mu peptide and DC-Chol/DOPE cationic liposomes were able to transfect an undifferentiated neuronal ND7 cell line with β-galactosidase reporter gene five-fold more effectively than lipoplex mixtures prepared from pCMVβ plasmid and DC-Chol/DOPE cationic liposomes. Mu was found to give an identical enhancement to cationic liposome-mediated transfection of ND7 cells as poly-L-lysine (pLL) or protamine sulfate (PA). The enhancing effects of mu were found to be even greater (six- to 10-fold) when differentiated ND7 cells were transfected with mu-containing lipopolyplex mixtures. Differentiated ND7 cells represent a simple ex vivo-like post-mitotic CNS cell system. Successful transfection of these cells bodes well for transfection of primary neurons and CNS cells in vivo. These findings have implications for experimental and therapeutic uses of cationic liposome-mediated delivery of nucleic acids to CNS cells.

We identified 14 mutations in 15 Japanese subjects from 13 families with galactose-1-phosphate uridyltransferase (GALT) deficiency using denaturing gradient gel electrophoresis (DGGE) and direct sequence analysis. These mutations accounted for 22 (96%) of 23 mutant alleles in 15 Japanese subjects. The mutational spectrum included nine missense mutations (M142V, G179D, A199T, R231H, W249R, N314D, P325L, R333Q, and R333W), two deletions (L275fsdelT and Q317fsdelC), a nonsense mutation (W249X), and two splicing mutations (V85-N97fsdel38bp and IVS4nt⁺1). Ten of the 14 mutations have not been reported in Caucasians. Differences in frequency and spectrum of GALT mutations suggest that the mutations may have occurred after racial divergence of Caucasians and Asians. The Duarte variant in Japanese was associated with the N314D mutation, g.1105G>C, g.1323G>A, and g.1391G>A (SacI -) polymorphisms, as in Caucasians. The Duarte variant may have occurred before racial divergence, and was an ancient mutation. In vitro GALT activities of nine missense mutations were determined by a COS cell expression system, and indicated between 1.3% and 35% of wild-type control. Patients with R333Q (29% in vitro GALT activity) or A199T (35%) showed mild clinical phenotypes, ie no ovarian failure or neurological deterioration. Genotype determination is useful for predicting biochemical and clinical phenotypes in classic galactosaemia, and can be of further help in managing patients with this disorder.

Hereditary non-syndromic deafness has been associated with a point mutation in the mitochondrial 12S rRNA gene. We present data from deaf individuals in 12 nuclear families originating from a small village in Zaire. The patients have a sudden-onset and profound, bilateral sensorineural deafness with a highly variable age of onset. Inheritance is compatible with a mitochondrial DNA defect. Sequencing of the mitochondrial 12S rRNA gene revealed the presence of a homoplasmic 1555 A to G mutation in the patients and their normal siblings. The mutation is invariably associated with a T to C transition at 1420 in the same gene. Additional (mitochondrial or autosomal) genetic defect(s) or an environmental factor must be implicated in the expression of the defect. In Epstein-Barr-virus-transformed lymphocytes harbouring the normal or mutant mitochondrial DNA, no differential effect of aminoglycosides on protein translation was observed.

Study Design: To determine the changes on gastric emptying and gastrointestinal transit of liquid throughout the first week after spinal cord transection (SCT) in rats. Methods: Male Wistar rats (n=121) were fasted for 16 h and a complete SCT or laminectomy was performed between C₇ and T₁ (cervical group) or between T₄ and T₅ (thoracic group). Dye recovery in the stomach, proximal, mid and distal small intestine was determined 30 min, 6 h, 1, 3 or 7 days after surgery. The test meal (1.5 ml of a phenol red solution, 0.5 mg/ml in 5% glucose) was intragastrically administered and the animals sacrificed by cervical dislocation 10 min later. Results: Cervical SCT increased dye recovery in the stomach (P<0.05) by 70.1, 78.7, 34.2, 41.3 and 50.9% while it decreased recovery in the mid small intestine (P<0.05) by 87.1, 85.1, 74.8, 59.5 and 80.1%, respectively 30 min, 6 h, 1, 3 and 7 days after SCT. Thoracic SCT increased gastric recovery (P<0.05) by 43.5, 67.6, 51.2, 75.4 and 38.9% while it decreased recovery in the mid small intestine (P<0.05) by 100, 100, 45.6, 100 and 66.6%, respectively 30 min, 6 h, 1, 3 and 7 days after SCT. A separate group was submitted to laminectomy+bilateral sciatic nerve transection (paraplegic sham). Gastric emptying and gastrointestinal transit were not inhibited in this group. Conclusion: In summary, gastric emptying and gastrointestinal transit of liquid are inhibited throughout the first week after high SCT in awake rats.

Here we show that a new class of antibiotics—acyldepsipeptides—has antibacterial activity against Gram-positive bacteria in vitro and in several rodent models of bacterial infection. The acyldepsipeptides are active against isolates that are resistant to antibiotics in clinical application, implying a new target, which we identify as ClpP, the core unit of a major bacterial protease complex. ClpP is usually tightly regulated and strictly requires a member of the family of Clp-ATPases and often further accessory proteins for proteolytic activation. Binding of acyldepsipeptides to ClpP eliminates these safeguards. The acyldepsipeptide-activated ClpP core is capable of proteolytic degradation in the absence of the regulatory Clp-ATPases. Such uncontrolled proteolysis leads to inhibition of bacterial cell division and eventually cell death.