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91.
Differential toxicity of TAR DNA‐binding protein 43 isoforms depends on their submitochondrial localization in neuronal cells 下载免费PDF全文
Illari Salvatori Alberto Ferri Silvia Scaricamazza Ilaria Giovannelli Alessia Serrano Simona Rossi Nadia D'Ambrosi Mauro Cozzolino Andrea Di Giulio Sandra Moreno Cristiana Valle Maria Teresa Carrì 《Journal of neurochemistry》2018,146(5):585-597
92.
Characterization of a truncated form of arrestin isolated from bovine rod outer segments. 总被引:4,自引:2,他引:4 下载免费PDF全文
K. Palczewski J. Buczylko H. Ohguro R. S. Annan S. A. Carr J. W. Crabb M. W. Kaplan R. S. Johnson K. A. Walsh 《Protein science : a publication of the Protein Society》1994,3(2):314-324
The inactivation of photolyzed rhodopsin requires phosphorylation of the receptor and binding of a 48-kDa regulatory protein, arrestin. By binding to phosphorylated photolyzed rhodopsin, arrestin inhibits G protein (Gt) activation and blocks premature dephosphorylation, thereby preventing the reentry of photolyzed rhodopsin into the phototransduction pathway. In this study, we isolated a 44-kDa form of arrestin, called p44, from fresh bovine rod outer segments and characterized its structure and function. A partial primary structure of p44 was established by a combination of mass spectrometry and automated Edman degradation of proteolytic peptides. The amino acid sequence was found to be identical with arrestin, except that the C-terminal 35 residues (positions 370-404) are replaced by a single alanine. p44 appeared to be generated by alternative mRNA splicing, because intron 15 interrupts within the nucleotide codon for 369Ser in the arrestin gene. Functionally, p44 binds avidly to photolyzed or phosphorylated and photolyzed rhodopsin. As a consequence of its relatively high affinity for bleached rhodopsin, p44 blocks Gt activation. The binding characteristics of p44 set it apart from tryptic forms of arrestin (truncated at the N- and C-termini), which require phosphorylation of rhodopsin for tight binding. We propose that p44 is a novel splice variant of arrestin that could be involved in the regulation of Gt activation. 相似文献
93.
Nonalcoholic fatty liver disease and measures of early brain health in middle‐aged adults: The CARDIA study 下载免费PDF全文
94.
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96.
Sevillano LG Melero CP Boya M López JL Tomé F Caballero E Carrón R Montero MJ Medarde M Feliciano AS 《Bioorganic & medicinal chemistry》1999,7(12):74-3001
A synthetic approach to hydroindenic inotropic agents has been developed, starting from enantiopure Hajos-Parrish (1). Hajos-Wiechert (2), and related diketones. Their transformation into C-1 formyl derivatives and other subsequent synthetic targets is described. The results of the thermodynamic equilibration between both epimers of each formyl derivative are analysed. The inotropic activities of selected compounds on right and left atrial preparations are also evaluated and discussed. 相似文献
97.
Vitamin K uptake in hepatocytes and hepatoma cells 总被引:1,自引:0,他引:1
Hepatocellular carcinoma (HCC) or hepatoma cells have impaired ability to perform vitamin K-dependent carboxylation reactions. Vitamin K can also inhibit growth of HCC cells in vitro. Both carboxylation and growth inhibition are vitamin K dose dependent. We used rat hepatocytes, a vitamin K-growth sensitive (MH7777) and a vitamin K-growth resistant (H4IIE) rat hepatoma cell line to examine vitamin K uptake and vitamin K-mediated microsomal carboxylation. We found that vitamin K is taken up by normal rat hepatocytes against a saturable concentration gradient. The relative rates of uptake by rat hepatocytes and the two rat cell lines MH7777 and H4IIE correlated with their sensitivity to vitamin K-mediated cell growth inhibition. Pooled hepatocytes from liver nodules from rats treated with the hepatocarcinogen diethylnitrosamine (DEN) also had a reduced rate of vitamin K uptake. However, using a cell-free system, microsomes from both normal rat hepatocytes and the two rat hepatoma cell lines had a similar ability to support carboxylation mediated by exogenously added vitamin K. The results support the hypothesis that different sensitivity of hepatoma cells to vitamin K may be due to differences in vitamin K uptake and may be unrelated to the actions of vitamin K on carboxylation. 相似文献
98.
Daniels JP Hunc K Cochrane DD Carr R Shaw NT Taylor A Heathcote S Brant R Lim J Ansermino JM 《CMAJ》2012,184(1):29-34
Background:
Identifying adverse events and near misses is essential to improving safety in the health care system. Patients are capable of reliably identifying and reporting adverse events. The effect of a patient safety reporting system used by families of pediatric inpatients on reporting of adverse events by health care providers has not previously been investigated.Methods:
Between Nov. 1, 2008, and Nov. 30, 2009, families of children discharged from a single ward of British Columbia’s Children’s Hospital were asked to respond to a questionnaire about adverse events and near misses during the hospital stay. Rates of reporting by health care providers for this period were compared with rates for the previous year. Family reports for specific incidents were matched with reports by health care providers to determine overlap.Results:
A total of 544 familes responded to the questionnaire. The estimated absolute increase in reports by health care providers per 100 admissions was 0.5% (95% confidence interval −1.8% to 2.7%). A total of 321 events were identified in 201 of the 544 family reports. Of these, 153 (48%) were determined to represent legitimate patient safety concerns. Only 8 (2.5%) of the adverse events reported by families were also reported by health care providers.Interpretation:
The introduction of a family-based system for reporting adverse events involving pediatric inpatients, administered at the time of discharge, did not change rates of reporting of adverse events and near misses by health care providers. Most reports submitted by families were not duplicated in the reporting system for health care providers, which suggests that families and staff members view safety-related events differently. However, almost half of the family reports represented legitimate patient safety concerns. Families appeared capable of providing valuable information for improving the safety of pediatric inpatients.It has been estimated that adverse events occur in about 1% of children treated in hospital and that, on average, 60% of these events are preventable.1 To increase institutional awareness of adverse events, hospitals have implemented systems to encourage health care providers to report adverse events.2 The reporting of adverse events can be improved by making electronic systems for reporting readily accessible3 and by ensuring a “just culture,” which includes nonpunitive reporting policies.4 However, adverse events reported by health care providers account for only a small fraction of total adverse events as determined by chart review.5 Time pressures to treat patients, fear of punishment, lack of belief in the benefit of reporting and differing opinions of what defines a reportable event contribute to low reporting rates.6 However, patients and their families are readily available, keen and motivated observers who may not be subject to these reporting barriers. Family members are capable of observing and reporting adverse events in a variety of clinical settings.7 It is known that the interpretation of safety events and the threshold for reporting differ among health care disciplines and individual health care providers.6 However, it is not clear how families of pediatric patients interpret safety-related events or what their threshold would be for reporting events.The purpose of this study was to test whether the introduction of an adverse event reporting system for use by families of pediatric patients at the time of discharge from a surgical ward would significantly change the rate of reporting of adverse events by health care providers. We also evaluated the types of events that families reported, the relevance of these events with respect to patient safety, families’ desires for anonymous reporting and families’ assessments of institutional responses to reported events. We anticipated that health care providers’ reporting rates would rise with the introduction of the family reporting system, on the assumption that greater attention would be paid to reporting safety-related events on the ward. We also anticipated that families would provide useful information about safety-related events, at least some of the time. In particular, we thought that facilitating communication from the patient’s family directly to the study institution’s Quality, Safety and Outcome Improvement Department would allow more opportunities to improve safety through changes in practice. 相似文献99.
A. Soteriou M. D. Carr T. A. Frenkiel J. E. McCormick C. J. Bauer D. Šali B. Birdsall J. Feeney 《Journal of biomolecular NMR》1993,3(5):535-546
Summary
13C-based three-dimensional 1H–1H correlation experiments have been used to determine essentially complete 13C and 1H resonance assignments for the amino acid side chains of uniformly 13C/15N labelled L. casei dihydrofolate reductase in a complex with the drug methotrexate. Excellent agreement is observed between these assignments and an earlier set of partial assignments made on the basis of correlating nuclear Overhauser effect and crystal structure data, indicating that the tertiary structure of the enzyme is similar in solution and in the crystal state.To whom correspondence should be addressed. 相似文献
100.
Spheroplasts have been prepared from the photosynthetic purple sulfur bacterium Chromatium vinosum by lysozyme plus ethylenediaminetetraacetic acid treatment. These spheroplasts are able to take up alanine in the light, but light-dependent alanine uptake is lost upon subsequent washing of the spheroplasts. The observations that alanine uptake driven by a potassium plus valinomycin-induced membrane potential (outside positive) is not affected by washing and that light-dependent alanine uptake can be restored by addition of the supernatant from washing suggest that a soluble electron carrier is lost during washing. Light-dependent alanine uptake in washed spheroplasts could be restored by addition of C. vinosum cytochrome c-551. Other soluble electron carriers from C. vinosum (high-potential iron protein, cytochrome ‘f’, cytochrome c′ and the flavocytochrome c-552) did not restore alanine uptake nor did a variety of other soluble electron carrier proteins from other organisms. These results suggest that cytochrome c-551 functions as an electron carrier in the cyclic electron transfer chain of C. vinosum. Mitochondrial cytochrome c (equine heart) and cytochrome c-551 from Pseudomonas aeruginosa were highly effective in restoring light-dependent alanine uptake in washed spheroplasts, making it likely that C. vinosum cytochrome c-551 is related by evolution to the same cytochrome c family as these other two c cytochromes. 相似文献