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61.
The objective of this study was to evaluate the clinical efficacy and safety of nitroprusside injection for preventing the slow-flow/no-reflow phenomenon after percutaneous coronary intervention (PCI). We searched the Cochrane Central Register of Controlled Trials (Issue 2, 2011), PubMed, EMbase, and Google Scholar for data. Two reviewers independently evaluated the quality of the included studies and extracted the data. A meta-analysis was performed using RevMan 5.0 software. Four randomized controlled trials (RCTs) involving 319 patients were included. The results of the meta-analyses showed that intracoronary nitroprusside is beneficial in preventing no-reflow/slow-flow, in reducing corrected TIMI frame count, and in improving left ventricular ejection fraction. It also likely reduces adverse reactions in patients after PCI and rehospitalization due to cardiovascular events. However, we must caution that in this review, there is a moderate possibility of bias with regard to patient selection, performance, and publication because of the small number of included studies. A larger sample size and high-quality RCTs are needed for a more reassuring analysis. 相似文献
62.
Larry M. Palato Shannon Pilcher Alissa Oakes Arleen Lamba Jaris Torres Litza I. Ledesma Monjaraz Crystabel Munoz Edward Njoo Dillon J. Rinauro Kate Alexandra Menefee Angela Tun Betssy L. Jauregui Sarah Shapiro Olivia H. Nossiff Eileen Olivares Kevin Chang Viviane Nguyen Luiza A. Nogaj David A. Moffet 《Journal of peptide science》2019,25(8)
The aggregation of the 37‐amino acid polypeptide human islet amyloid polypeptide (hIAPP), as either insoluble amyloid or as small oligomers, appears to play a direct role in the death of human pancreatic β‐islet cells in type 2 diabetes. hIAPP is considered to be one of the most amyloidogenic proteins known. The quick aggregation of hIAPP leads to the formation of toxic species, such as oligomers and fibers, that damage mammalian cells (both human and rat pancreatic cells). Whether this toxicity is necessary for the progression of type 2 diabetes or merely a side effect of the disease remains unclear. If hIAPP aggregation into toxic amyloid is on‐path for developing type 2 diabetes in humans, islet amyloid polypeptide (IAPP) aggregation would likely need to play a similar role within other organisms known to develop the disease. In this work, we compared the aggregation potential and cellular toxicity of full‐length IAPP from several diabetic and nondiabetic organisms whose aggregation propensities had not yet been determined for full‐length IAPP. 相似文献
63.
Influence of a freeze-thaw cycle on the stress-stretch curves of tissues of porcine abdominal organs
NH Nguyn MT D Ng TN Trn PT Phạm O Grottke R Tolba M Staat 《Journal of biomechanics》2012,45(14):2382-2386
The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze-thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze-thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines. 相似文献
64.
65.
Tun Nurul Aimi Mat Jaafar Martin I. Taylor Siti Azizah Mohd Nor Mark de Bruyn Gary R. Carvalho 《PloS one》2012,7(11)
Background
DNA barcodes, typically focusing on the cytochrome oxidase I gene (COI) in many animals, have been used widely as a species-identification tool. The ability of DNA barcoding to distinguish species from a range of taxa and to reveal cryptic species has been well documented. Despite the wealth of DNA barcode data for fish from many temperate regions, there are relatively few available from the Southeast Asian region. Here, we target the marine fish Family Carangidae, one of the most commercially-important families from the Indo-Malay Archipelago (IMA), to produce an initial reference DNA barcode library.Methodology/Principal Findings
Here, a 652 bp region of COI was sequenced for 723 individuals from 36 putative species of Family Carangidae distributed within IMA waters. Within the newly-generated dataset, three described species exhibited conspecific divergences up to ten times greater (4.32–4.82%) than mean estimates (0.24–0.39%), indicating a discrepancy with assigned morphological taxonomic identification, and the existence of cryptic species. Variability of the mitochondrial DNA COI region was compared within and among species to evaluate the COI region''s suitability for species identification. The trend in range of mean K2P distances observed was generally in accordance with expectations based on taxonomic hierarchy: 0% to 4.82% between individuals within species, 0% to 16.4% between species within genera, and 8.64% to 25.39% between genera within families. The average Kimura 2-parameter (K2P) distance between individuals, between species within genera, and between genera within family were 0.37%, 10.53% and 16.56%, respectively. All described species formed monophyletic clusters in the Neighbour-joining phylogenetic tree, although three species representing complexes of six potential cryptic species were detected in Indo-Malay Carangidae; Atule mate, Selar crumenophthalmus and Seriolina nigrofasciata.Conclusion/Significance
This study confirms that COI is an effective tool for species identification of Carangidae from the IMA. There were moderate levels of cryptic diversity among putative species within the central IMA. However, to explain the hypothesis of species richness in the IMA, it is necessary to sample the whole family across their broad geographic range. Such insights are helpful not only to document mechanisms driving diversification and recruitment in Carangidae, but also to provide a scientific framework for management strategies and conservation of commercially-important fisheries resources. 相似文献66.
Sitry D Seeliger MA Ko TK Ganoth D Breward SE Itzhaki LS Pagano M Hershko A 《The Journal of biological chemistry》2002,277(44):42233-42240
Previous studies have shown that the cyclin-dependent kinase (Cdk) inhibitor p27(Kip1) is targeted for degradation by an SCF(Skp2) ubiquitin ligase complex and that this process requires Cks1, a member of the highly conserved Suc1/Cks family of cell cycle regulatory proteins. All proteins of this family have Cdk-binding and anion-binding sites, but only mammalian Cks1 binds to Skp2 and promotes the association of Skp2 with p27 phosphorylated on Thr-187. The molecular mechanisms by which Cks1 promotes the interaction of the Skp2 ubiquitin ligase subunit to p27 remained obscure. Here we show that the Skp2-binding site of Cks1 is located on a region including the alpha2- and alpha1-helices and their immediate vicinity, well separated from the other two binding sites. All three binding sites of Cks1 are required for p27-ubiquitin ligation and for the association of Skp2 with Cdk-bound, Thr-187-phosphorylated p27. Cks1 and Skp2 mutually promote the binding of each other to a peptide similar to the 19 C-terminal amino acids of p27 containing phosphorylated Thr-187. This latter process requires the Skp2- and anion-binding sites of Cks1, but not its Cdk-binding site. It is proposed that the Skp2-Cks1 complex binds initially to the C-terminal region of phosphorylated p27 in a process promoted by the anion-binding site of Cks1. The interaction of Skp2 with the substrate is further strengthened by the association of the Cdk-binding site of Cks1 with Cdk2/cyclin E, to which phosphorylated p27 is bound. 相似文献
67.
Gonad morphology and structure of sex cells in juvenile triploid trout Oncorhynchus mykiss of the Donaldson breed incubated and reared at a trout plant under climatic conditions of South Vietnam have been studied. Anomalies in the structure of sex gonads and oocyte structure were found, and partial resorption of sex cells was detected. It was shown that sex inversion in triploid (unisexual) fingerlings of rainbow trout passed successfully on the whole since many sex gonads of these fish simultaneously had both female and male sex cells and sometimes were sterile. The connection of anomalies found in the structure of sex system of trout with species rearing under unusual for it climatic conditions and artificial sex inversion is discussed. 相似文献
68.
Dynamin-related proteins (DRPs) are key components of the organelle division machineries, functioning as molecular scissors during the fission process. In Arabidopsis, DRP3A and DRP3B are shared by peroxisomal and mitochondrial division, whereas the structurally-distinct DRP5B (ARC5) protein is involved in the division of chloroplasts and peroxisomes. Here, we further investigated the roles of DRP3A, DRP3B, and DRP5B in organelle division and plant development. Despite DRP5B's lack of stable association with mitochondria, drp5B mutants show defects in mitochondrial division. The drp3A-2 drp3B-2 drp5B-2 triple mutant exhibits enhanced mitochondrial division phenotypes over drp3A-2 drp3B-2, but its peroxisomal morphology and plant growth phenotypes resemble those of the double mutant. We further demonstrated that DRP3A and DRP3B form a supercomplex in vivo, in which DRP3A is the major component, yet DRP5B is not a constituent of this complex. We thus conclude that DRP5B participates in the division of three types of organelles in Arabidopsis, acting independently of the DRP3 complex. Our findings will help elucidate the precise composition of the DRP3 complex at organelle division sites, and will be instrumental to studies aimed at understanding how the same protein mediates the morphogenesis of distinct organelles that are linked by metabolism. 相似文献
69.
Preparation of cellulose carbonate 总被引:2,自引:0,他引:2
70.
U Kyaw Tha Paw 《International journal of biometeorology》1988,32(2):73-77
Clustering of organisms under cold air temperature conditions is modelled with a finite-difference method. Metabolic functions of temperature are used to simulate completely ectothermic, completely endothermic, and other organisms. To adequately match real conditions, the core temperature is kept constant at a high level, while the periphery of the organism cluster is assigned a lower temperature representing the cold conditions under which clustering is observed for organisms. The numerical model reasonably predicts the observed temperature distribution in honeybee clusters. The results do not support suggestions that organisms could overheat in the core of a cluster if they do not use thermoregulatory mechanisms to cool down. Endothermic organisms are not as efficient as ectothermic ones in heating a cluster core temperature to a given level. The general ectothermic metabolic rate function exhibited one of the highest efficiencies for heating the cluster. 相似文献