The 1-year spontaneous mortality rate in patients with Budd-Chiari syndrome (BCS) approaches 70%. No prospective assessment of indications and impact on survival of current therapeutic procedures has been performed. We evaluated a therapeutic strategy uniformly applied during the last 8 years in a single referral center. Fifty-one consecutive patients first received anticoagulation and were treated for associated diseases. Symptomatic patients were considered for hepatic vein recanalization; then for transjugular intrahepatic portosystemic shunt (TIPS), and finally for liver transplantation. The absence of a complete response led to the next procedure. Assessment was according to the strategy, whether procedures were technically applicable and successful. At entry, median (range) Child-Pugh score and Clichy prognostic index were 8 (5-12), and 5.4 (3.1-7.7), respectively. A complete response was achieved on medical therapy alone in 9 patients; after recanalization in 6, TIPS in 20, liver transplantation in 9, and retransplantation in 1. Of the 41 patients considered for recanalization, the procedure was not feasible in 27 and technically unsuccessful in 3. Of the 34 patients considered for TIPS, the procedure was considered not feasible in 9 and technically unsuccessful in 4. At 1 year of follow-up, a complete response to TIPS was achieved in 84%. One-and 5-year survival from starting anticoagulation were 96% (95% CI, 90-100) and 89% (95% CI, 79-100), respectively. In conclusion, excellent survival can be achieved in BCS patients when therapeutic procedures are introduced by order of increasing invasiveness, based on the response to previous therapy rather than on the severity of the patient's condition. (HEPATOLOGY 2006;44:1308-1316
Many different cells' signalling pathways are universally regulated by Ca2+ concentration [Ca2+] rises that have highly variable amplitudes and kinetic properties. Optical imaging can provide the means to characterise both the temporal and spatial aspects of Ca2+ signals involved in neurophysiological functions. New methods for in vivo imaging of Ca2+ signalling in the brain of Drosophila are required for probing the different dynamic aspects of this system. In studies here, whole brain Ca2+ imaging was performed on transgenic flies with targeted expression of the bioluminescent Ca2+ reporter GFP-aequorin (GA) in different neural structures. A photon counting based technique was used to undertake continuous recordings of cytosolic [Ca2+] over hours. Time integrals for reconstructing images and analysis of the data were selected offline according to the signal intensity. This approach allowed a unique Ca2+ response associated with cholinergic transmission to be identified by whole brain imaging of specific neural structures. Notably, [Ca2+] transients in the Mushroom Bodies (MBs) following nicotine stimulation were accompanied by a delayed secondary [Ca2+] rise (up to 15 min. later) in the MB lobes. The delayed response was sensitive to thapsigargin, suggesting a role for intra-cellular Ca2+ stores. Moreover, it was reduced in dunce mutant flies, which are impaired in learning and memory. Bioluminescence imaging is therefore useful for studying Ca2+ signalling pathways and for functional mapping of neurophysiological processes in the fly brain.
We have previously demonstrated that adult pig islets of Langerhans are not destroyed in vitro by primate sera. Whether these islets can function when placed into the liver of non-human primates is not known. We now report on the outcome of pig islet xenotransplantation into five non diabetic primates (four baboons and one macacus fascicularis) receiving intraportally purified adult pig islets. The average number of islet-equivalent per graft was 110,000 (60-180,000). All animals received associations of ATG, cyclosporine or LF 195 (a deoxyspergualin analog), mycophenolate mofetil and corticosteroids. A specific porcine C-peptide (C-pep) RIA test was used to monitor insulin secretion. Two hours after grafting, porcine C-peptide was positive (from 0.37 to 4.25 ng/ml) in all monkeys except one. Primate C-pep was normal in all cases. Only two monkeys had detectable levels of porcine C-pep on day 1 or 2 with undetectable levels thereafter, even after glucagon challenge between days 6 and 10. Several normal islets with moderate inflammatory infiltration were observed in one animal liver on day 2 (the time of necropsy) as well as islets with IgM and complement deposition. Among animals sacrificed on days 14, 16 and 38, some residual islet cells could be identified only in livers collected on day 14. Partial glycaemic control was achieved in some rats receiving islets from the same preparations. In conclusion, adult pig islets are not able to maintain insulin secretion for more than 24 h when injected intraportally into non diabetic immunosuppressed monkeys. suggesting immediate islet xenograft destruction.
mRNA levels result from an equilibrium between transcription and degradation. Ribonucleases (RNases) facilitate the turnover of mRNA, which is an important way of controlling gene expression, allowing the cells to adjust transcript levels to a changing environment. In contrast to the heterotrophic model bacteria Escherichia coli and Bacillus subtilis, RNA decay has not been studied in detail in cyanobacteria. Synechocystis sp. PCC6803 encodes orthologs of both E. coli and B. subtilis RNases, including RNase E and RNase J, respectively. We show that in vitro Sy RNases E and J have an endonucleolytic cleavage specificity that is very similar between them and also compared to orthologous enzymes from E. coli, B. subtilis, and Chlamydomonas. Moreover, Sy RNase J displays a robust 5 -exoribonuclease activity similar to B. subtilis RNase J1, but unlike the evolutionarily related RNase J in chloroplasts. Both nucleases are essential and gene deletions could not be fully segregated in Synechocystis. We generated partially disrupted strains of Sy RNase E and J that were stable enough to allow for their growth and characterization. A transcriptome analysis of these strains partially depleted for RNases E and J, respectively, allowed to observe effects on specific transcripts. RNase E altered the expression of a larger number of chromosomal genes and antisense RNAs compared to RNase J, which rather affects endogenous plasmid encoded transcripts. Our results provide the first description of the main transcriptomic changes induced by the partial depletion of two essential ribonucleases in cyanobacteria.
It is well established that Zif268/Egr1 , a member of the Egr family of transcription factors, is critical for the consolidation of several forms of memory; however, it is as yet uncertain whether increasing expression of Zif268 in neurons can facilitate memory formation. Here, we used an inducible transgenic mouse model to specifically induce Zif268 overexpression in forebrain neurons and examined the effect on recognition memory and hippocampal synaptic transmission and plasticity. We found that Zif268 overexpression during the establishment of memory for objects did not change the ability to form a long-term memory of objects, but enhanced the capacity to form a long-term memory of the spatial location of objects. This enhancement was paralleled by increased long-term potentiation in the dentate gyrus of the hippocampus and by increased activity-dependent expression of Zif268 and selected Zif268 target genes. These results provide novel evidence that transcriptional mechanisms engaging Zif268 contribute to determining the strength of newly encoded memories.
Vertebrate CASK is a member of the membrane-associated guanylate kinase (MAGUK) family of proteins. CASK is present in the nervous system where it binds to neurexin, a transmembrane protein localized in the presynaptic membrane. The Drosophila homologue of CASK is CAKI or CAMGUK. CAKI is expressed in the nervous system of larvae and adult flies. In adult flies, the expression of caki is particularly evident in the visual brain regions. To elucidate the functional role of CASK, we employed a caki null mutant in the model organism Drosophila melanogaster. By means of electrophysiological methods, we analyzed, in adult flies, the spontaneous and evoked neurotransmitter release at the neuromuscular junction (NMJ) as well as the functional status of the giant fiber pathway and of the visual system. We found that in caki mutants, when synaptic activity is modified, the spontaneous neurotransmitter release of the indirect flight muscle NMJ was increased, the response of the giant fiber pathway to continuous stimulation was impaired, and electroretinographic responses to single and continuous repetitive stimuli were altered and optomotor behavior was abnormal. These results support the involvement of CAKI in neurotransmitter release and nervous system function.
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