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101.
102.
Glutamate metabolism in cerebral mitochondria after ischemia and post‐ischemic recovery during aging: relationships with brain energy metabolism 下载免费PDF全文
Federica Ferrari Antonella Gorini Siegfried Hoyer Roberto Federico Villa 《Journal of neurochemistry》2018,146(4):416-428
103.
Scotti C Iamele L Alessandrini A Vannini V Cazzalini O Lazzè MC Melli R Savio M Pizzala R Stivala LA Biglieri S Tomasi A Bianchi L 《Mitochondrion》2003,2(5):361-373
We investigated the molecular relationships between lipid peroxidation and mitochondrial DNA (mtDNA) single strand breaks (ssb) in isolated rat hepatocytes and mitochondria exposed to tert-butylhydroperoxide (TBH). Our results show that mtDNA ssb induced by TBH are independent of lipid peroxidation and dependent on the presence of iron and of hydroxyl free radicals. These data contribute to the definition of the mechanisms whereby mtDNA ssb are induced and provide possible molecular targets for the prevention of this kind of damage in vivo. 相似文献
104.
Kátia Regina da Silva Roberto Costa Elizabeth Sartori Crevelari Marianna Sobral Lacerda Caio Marcos de Moraes Albertini Martino Martinelli Filho José Eduardo Santana Jo?o Ricardo Nickenig Vissoci Ricardo Pietrobon Jacson V. Barros 《PloS one》2013,8(7)
Background
The ability to apply standard and interoperable solutions for implementing and managing medical registries as well as aggregate, reproduce, and access data sets from legacy formats and platforms to advanced standard formats and operating systems are crucial for both clinical healthcare and biomedical research settings.Purpose
Our study describes a reproducible, highly scalable, standard framework for a device registry implementation addressing both local data quality components and global linking problems.Methods and Results
We developed a device registry framework involving the following steps: (1) Data standards definition and representation of the research workflow, (2) Development of electronic case report forms using REDCap (Research Electronic Data Capture), (3) Data collection according to the clinical research workflow and, (4) Data augmentation by enriching the registry database with local electronic health records, governmental database and linked open data collections, (5) Data quality control and (6) Data dissemination through the registry Web site. Our registry adopted all applicable standardized data elements proposed by American College Cardiology / American Heart Association Clinical Data Standards, as well as variables derived from cardiac devices randomized trials and Clinical Data Interchange Standards Consortium. Local interoperability was performed between REDCap and data derived from Electronic Health Record system. The original data set was also augmented by incorporating the reimbursed values paid by the Brazilian government during a hospitalization for pacemaker implantation. By linking our registry to the open data collection repository Linked Clinical Trials (LinkedCT) we found 130 clinical trials which are potentially correlated with our pacemaker registry.Conclusion
This study demonstrates how standard and reproducible solutions can be applied in the implementation of medical registries to constitute a re-usable framework. Such approach has the potential to facilitate data integration between healthcare and research settings, also being a useful framework to be used in other biomedical registries. 相似文献105.
Differences in the chitinolytic activity of mammalian chitinases on soluble and insoluble substrates
Benjamin A. Barad Lin Liu Roberto E. Diaz Ralp Basilio Steven J. Van Dyken Richard M. Locksley James S. Fraser 《Protein science : a publication of the Protein Society》2020,29(4):952-963
Chitin is an abundant polysaccharide used by many organisms for structural rigidity and water repulsion. As such, the insoluble crystalline structure of chitin poses significant challenges for enzymatic degradation. Acidic mammalian chitinase, a processive glycosyl hydrolase, is the primary enzyme involved in the degradation of environmental chitin in mammalian lungs. Mutations to acidic mammalian chitinase have been associated with asthma, and genetic deletion in mice increases morbidity and mortality with age. We initially set out to reverse this phenotype by engineering hyperactive acidic mammalian chitinase variants. Using a screening approach with commercial fluorogenic substrates, we identified mutations with consistent increases in activity. To determine whether the activity increases observed were consistent with more biologically relevant chitin substrates, we developed new assays to quantify chitinase activity with insoluble chitin, and identified a one‐pot fluorogenic assay that is sufficiently sensitive to quantify changes to activity due to the addition or removal of a carbohydrate‐binding domain. We show that the activity increases from our directed evolution screen were lost when insoluble substrates were used. In contrast, naturally occurring gain‐of‐function mutations gave similar results with oligomeric and insoluble substrates. We also show that activity differences between acidic mammalian chitinase and chitotriosidase are reduced with insoluble substrate, suggesting that previously reported activity differences with oligomeric substrates may have been driven by differential substrate specificity. These results highlight the need for assays against physiological substrates when engineering metabolic enzymes, and provide a new one‐pot assay that may prove to be broadly applicable to engineering glycosyl hydrolases. 相似文献
106.
Piero Pollesello Renato Toffanin Erminio Murano Roberto Rizzo Sergio Paoletti Bjarne J. Kvam 《Journal of applied phycology》1992,4(2):149-155
Lipid extracts of the red algaGracilaria longa were studied by1H- and13C-NMR spectroscopy. Peaks in the13C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g
wet alga was estimated from the1H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The13C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison
between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation
and some glycolipid degradation during the drying process. 相似文献
107.
Melgar-Fernández R Demare P Hong E Rosas MA Escalante J Muñoz-Muñiz O Juaristi E Regla I 《Bioorganic & medicinal chemistry letters》2004,14(1):191-194
The synthesis of four novel analogues of metoprolol, a well-known beta1-blocker used to reduce arterial blood pressure, is described. The preparation of (2S,2'S)-7, (2R,2'S)-7, (2R,2'R)-8, and (2S,2'R)-8 was based on the reaction of racemic 2-[4-(2'-methoxyethyl)-phenoxymethyl]-oxirane (4) with (R)- or (S)-2-amino-1-butanol. Salient characteristics of analogues 7 and 8 relative to metoprolol are the incorporation of an additional stereogenic center, as well as a methyl group and a hydroxyl function on the nitrogen-containing chain. These novel derivatives present significant hypotensive and bradycardiac activity, although no blocking action toward beta1 and beta2 adrenergic receptor. 相似文献
108.
109.
Anatomy of the antennal dorsal organ in female of Neodryinus typhlocybae (Hymenoptera: Dryinidae): A peculiar sensory structure possibly involved in perception of host vibration 下载免费PDF全文
Paola Riolo Nunzio Isidoro Sara Ruschioni Roxana L. Minuz Ferdinando Bin Roberto Romani 《Journal of morphology》2016,277(1):128-137
Neodryinus typhlocybae (Hymenoptera: Dryinidae) is a natural enemy of the planthopper Metcalfa pruinosa, which was introduced from North America into Europe and has become established in various regions as a pest species. Vibrational signals play a crucial role in the communication of M. pruinosa, which appears to be exploited by N. typhlocybae. Scanning and transmission electron microscopy have shown that the antennae of N. typhlocybae females have peculiar and complex sensory structures: deep longitudinal grooves that house long sensilla trichodea, termed here “Antennal Dorsal Organs.” Such structures were not present on male antennae. These sensilla extend for the length of the grooves, without contact with the groove cuticle. Their hair shaft is empty and aporous, and inserted into a specialized socket, underneath which there is a cuticular ampulla‐like chamber. Each sensillum is associated with two sensory neurons: one terminates at the proximal end of the dendritic sheath; the other continues into the sensillum sinus and is enclosed in the dendritic sheath. This second sensory neuron then enters the ampulla‐like chamber through the circular opening, and then terminates with a conspicuous tubular body at the shaft base. The possible involvement of this peculiar structure in the context of host recognition mechanism is discussed. J. Morphol. 277:128–137, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
110.
This study aimed to test the concurrent validity of an electronic version (to run on tablet) of a sleep diary derived from the core Consensus Sleep Diary compared with the traditional paper and pencil version. To this end, 15 healthy volunteers (6 males; mean age 37.20 ± 17.55 years) every morning, for at least 7 consecutive days, filled both paper and electronic sleep diary. Furthermore, sleep was objectively assessed through actigraphy. With reference to all sleep parameters examined, no significant differences were observed between paper and electronic sleep diary. As expected, paper and electronic sleep diary showed the same poor agreement with actigraphic estimates of sleep quantity and sleep quality. On the basis of the present data, we can conclude that electronic sleep diary performs like paper sleep diary. Bearing in mind that electronic sleep diary presents several benefits in comparison to the paper sleep diary (e.g. avoiding of the “parking lot syndrome”, in which patient retrospectively completes more days at the same time; reducing the time for data entry and scoring), we suggest that, if the present findings will be confirmed also in clinical populations, electronic sleep diary should replace paper sleep diary in both research and clinical settings. 相似文献