| 1. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 2. |
- Li, Zhen, et al.
(författare)
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Regional heterogeneity of right atrial repolarization. Monophasic action potential mapping in swine.
- 2011
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Ingår i: Scandinavian cardiovascular journal : SCJ. - : Informa UK Limited. - 1651-2006 .- 1401-7431. ; 45, s. 336-341
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Objectives. To establish a set of reference values for regional dispersion of repolarization of the right atrium in the in situ heart of pigs and to see if the global dispersion of repolarization could be estimated from regional mapping. Design. Monophasic action potential (MAP) were sequentially recorded from 28 ± 3 sites in seven different regional areas of the right atrium: lateral, anterior and posterior wall, septum, sinoatrial node (SAN), appendage, and near the tricuspid annulus (TA) in 10 healthy pigs using the CARTO mapping system. Results. The activation time (AT), MAP duration (MAPd) and end of repolarization time (EOR) of the whole right atrium were 68 ± 7, 239 ± 20 and 270 ± 23 ms, respectively. There were no significant differences on MAPd and EOR among the seven regional areas, nor between each of the regional and global values. The global dispersions of the MAPd and EOR were 75 ± 19 and 103 ± 13 ms, which were significantly greater than those obtained from any of the seven regional areas and those between two remote regions, SAN vs. TA and SAN vs. appendage regions. Conclusions. The data of regional and global dispersion of repolarization in healthy pigs can serve as reference values for evaluation of increased dispersion of repolarization. The global dispersions of MAPd and EOR in the right atrium were poorly estimated from regional mapping, suggesting the importance of global mapping in evaluating the dispersion of atrial repolarization.
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| 3. |
- Li, Zhijian, et al.
(författare)
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Systematic exploration of essential yeast gene function with temperature-sensitive mutants.
- 2011
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Ingår i: Nature biotechnology. - : Springer Science and Business Media LLC. - 1546-1696 .- 1087-0156. ; 29:4, s. 361-7
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Tidskriftsartikel (refereegranskat)abstract
- Conditional temperature-sensitive (ts) mutations are valuable reagents for studying essential genes in the yeast Saccharomyces cerevisiae. We constructed 787 ts strains, covering 497 (∼45%) of the 1,101 essential yeast genes, with ∼30% of the genes represented by multiple alleles. All of the alleles are integrated into their native genomic locus in the S288C common reference strain and are linked to a kanMX selectable marker, allowing further genetic manipulation by synthetic genetic array (SGA)-based, high-throughput methods. We show two such manipulations: barcoding of 440 strains, which enables chemical-genetic suppression analysis, and the construction of arrays of strains carrying different fluorescent markers of subcellular structure, which enables quantitative analysis of phenotypes using high-content screening. Quantitative analysis of a GFP-tubulin marker identified roles for cohesin and condensin genes in spindle disassembly. This mutant collection should facilitate a wide range of systematic studies aimed at understanding the functions of essential genes.
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| 4. |
- Lu, Wen, et al.
(författare)
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Design concept of a narrow-wideband antenna for spectrum sensing applications
- 2011
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Konferensbidrag (refereegranskat)abstract
- Design concept of a novel combined antenna for cognitive radio applications is proposed and numerically verified. The antenna is composed of a wideband circular monopole and a narrowband dipole. The impedance bandwidth of the wideband monopole antenna is from 4.25-10GHz. The narrowband dipole antenna's central frequency is 5.8GHz. The isolation between the two elements is higher than 50dB, which indicates that the two elements independently co-exist within a small printed circuit board (PCB). The design concept proposed in this paper should be useful to the design and realization of compact, planar antennas and antenna modules having spectrum sensing function.
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| 5. |
- Moser, Debra K., et al.
(författare)
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Identification of symptom clusters among patients with heart failure: An international observational study
- 2014
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Ingår i: International Journal of Nursing Studies. - : Elsevier. - 0020-7489 .- 1873-491X. ; 51:10, s. 1366-1372
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Tidskriftsartikel (refereegranskat)abstract
- Background: Virtually all patients with heart failure experience multiple symptoms simultaneously, yet clinicians and researchers usually consider symptoms in isolation. Recognizing and responding early to escalating symptoms is essential to preventing hospitalizations in heart failure, yet patients have considerable difficulty recognizing symptoms. Identification of symptom clusters could improve symptom recognition, but cultural differences may be present that must be considered. Objectives: To identify and compare symptom clusters in heart failure patients from the United States, Europe and Asia. Design: Cross-sectional, observational study. Settings: In- and out-patient settings in three regions of the world: Asia (i.e., China and Taiwan); Europe (i.e., the Netherlands and Sweden); and the United States. Participants: A total of 720 patients with confirmed heart failure. Propensity scoring using New York Heart Association Classification was used to match participants from each of the three regions. Methods: Symptoms were identified using the Minnesota Living with Heart Failure Questionnaire. To identify symptom clusters we used cluster analysis with the hierarchical cluster agglomerative approach. We used the Euclidean distance to measure the similarity of variables. Proximity between groups of variables was measured using Wards method. The resulting clusters were displayed with dendrograms, which show the proximity of variables to each other on the basis of semi-partial R-squared scores. Results: There was a core group of symptoms that formed two comparable clusters across the countries. Dyspnea, difficulty in walking or climbing, fatigue/increased need to rest, and fatigue/low energy were grouped into a cluster, which was labeled as a physical capacity symptom cluster. Worrying, feeling depressed, and cognitive problems were grouped into a cluster, which was labeled as an emotional/cognitive symptom cluster. The symptoms of edema and trouble sleeping were variable among the countries and fell into different clusters. Conclusion: Despite the diversity in cultures studied, we found that symptoms clustered similarly among the cultural groups. Identification of similar symptoms clusters among patients with heart failure may improve symptom recognition in both patients and healthcare providers.
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| 6. |
- Yuan, Na-Juan, et al.
(författare)
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A Study of Mn(II) Ion Capture by Mesoporous Silica
- 2011
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Ingår i: Adsorption Science and Technology. - : Hindawi Limited. - 0263-6174 .- 2048-4038. ; 29:4, s. 345-356
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Tidskriftsartikel (refereegranskat)abstract
- The removal of Mn(II) ions from water using mesoporous silica as the adsorbent material is discussed. The mesoporous silica was prepared in an economic manner through the use of sodium silicate as an inexpensive source of silica and decaoxyethylene cetyl ether [C-16(EO)(10)] as the template agent. The properties of the material were characterized and its adsorption capacity for Mn(II) ions from aqueous solution investigated by varying parameters such as the pH of the initial suspension, the contact time, the initial concentration of Mn(II) ions in the solution and the adsorbent dosage. With no subsequent modification, the prepared materials exhibited a high adsorption capability towards Mn(II) ions with q(e) = 44 mg/g. The adsorption isotherms could be described by both the Langmuir and Freundlich models, the former model providing a better representation of the adsorption process. Characterization using UV-vis spectroscopy, nitrogen sorption isotherms and thermogravimetric analysis after adsorption indicated that the Mn(II) ions were adsorbed onto the mesoporous silica surface.
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