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Evidence for the functions of surface‐active behaviors in humpback whales (Megaptera novaeangliae) 下载免费PDF全文
Ailbhe S. Kavanagh Kylie Owen Michael J. Williamson Simon P. Blomberg Michael J. Noad Anne W. Goldizen Eric Kniest Douglas H. Cato Rebecca A. Dunlop 《Marine Mammal Science》2017,33(1):313-334
As part of their social sound repertoire, migrating humpback whales (Megaptera novaeangliae) perform a large variety of surface‐active behaviors, such as breaching and repetitive slapping of the pectoral fins and tail flukes; however, little is known about what factors influence these behaviors and what their functions might be. We investigated the potential functions of surface‐active behaviors in humpback whale groups by examining the social and environmental contexts in which they occurred. Focal observations on 94 different groups of whales were collected in conjunction with continuous acoustic monitoring, and data on the social and environmental context of each group. We propose that breaching may play a role in communication between distant groups as the probability of observing this behavior decreased significantly when the nearest whale group was within 4,000 m compared to beyond 4,000 m. Involvement in group interactions, such as the splitting of a group or a group joining with other whales, was an important factor in predicting the occurrence of pectoral, fluke, and peduncle slapping, and we suggest that they play a role in close‐range or within‐group communication. This study highlights the potentially important and diverse roles of surface‐active behaviors in the communication of migrating humpback whales. 相似文献
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PA Naesgaard RA León De La Fuente ST Nilsen L Woie T Aarsland C Brede H Staines DW Nilsen 《PloS one》2012,7(9):e43228
Background
Several studies have shown an association between vitamin D deficiency and cardiovascular risk. Vitamin D status is assessed by determination of 25-hydroxyvitamin D [25(OH)D] in serum.Methods
We assessed the prognostic utility of 25(OH)D in 982 chest-pain patients with suspected acute coronary syndrome (ACS) from Salta, Northern Argentina. 2-year follow-up data including all-cause mortality, cardiac death and sudden cardiac death were analyzed in quartiles of 25(OH)D, applying univariate and multivariate analysis.Results
There were statistically significant changes in seasonal 25(OH)D levels. At follow-up, 119 patients had died. The mean 25(OH)D levels were significantly lower among patients dying than in long-term survivors, both in the total population and in patients with a troponin T (TnT) release (n = 388). When comparing 25(OH)D in the highest quartile to the lowest quartile in a multivariable Cox regression model for all-cause mortality, the hazard ratio (HR) for cardiac death and sudden cardiac death in the total population was 0.37 (95% CI, 0.19–0.73), p = 0.004, 0.23 (95% CI, 0.08–0.67), p = 0.007, and 0.32 (95% CI, 0.11–0.94), p = 0.038, respectively. In patients with TnT release, the respective HR was 0.24 (95% CI, 0.10–0.54), p = 0.001, 0.18 (95% CI, 0.05–0.60), p = 0.006 and 0.25 (95% CI, 0.07–0.89), p = 0.033. 25(OH)D had no prognostic value in patients with no TnT release.Conclusion
Vitamin D was shown to be a useful biomarker for prediction of mortality when obtained at admission in chest pain patients with suspected ACS.Trial registration
ClinicalTrials.gov NCT01377402相似文献4.
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Mark A. Seefeld Hong Lin Joerg Holenz Dave Downie Brian Donovan Tingting Fu Kishore Pasikanti Wei Zhen Matthew Cato Khuram W. Chaudhary Pat Brady Tania Bakshi Dwight Morrow Sridharan Rajagopal Swapan Kumar Samanta Naveena Madhyastha Bharathi Mohan Kuppusamy Robert W. Dougherty Yasuji Matsuoka 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3793-3797
Neuronal voltage-gated potassium channels, KV7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule KV7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. KV7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual KV7 isoforms was investigated in human detrusor tissue using a panel of KV7 openers with distinct activity profiles among KV7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric KV7.4 did not reduce detrusor contraction. This may suggest that the homomeric KV7.4 channel plays a less significant role in bladder contraction and further investigation is needed. 相似文献
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A rapid PCR-based method for genetically mapping ESTs 总被引:12,自引:0,他引:12
S. A. Cato R. C. Gardner J. Kent T. E. Richardson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(2-3):296-306
A simple, semi-automatable procedure was developed for converting expressed sequence tags (ESTs) into mappable genetic markers.
The polymerase chain reaction is used to amplify regions immediately 5′ or 3′ to the coding regions of genes in order to maximise
sequence variability between alleles. Fragment length and nucleotide substitution polymorphisms among amplified alleles can
be detected using either ethidium bromide staining or automated laser-based fluorescence. A 6% non-denaturing acrylamide gel,
analysed with an ABI 377 DNA sequencer, proved capable of resolving homoduplexes and heteroduplexes formed between amplified
alleles containing nucleotide substitutions as well as resolving allelic length differences. With this approach 75% of 60
ESTs from a range of Pinus species could be genetically mapped in each of three pedigrees from P. radiata and P. taeda. Furthermore, three or four alleles were detected in each pedigree for 42% of the EST markers.
Received: 4 January 2000 / Accepted: 26 May 2000 相似文献
10.
Benny Bj?rkblom Altynai Adilbayeva Jodi Maple-Gr?dem Dominik Piston Mats ?kvist Xiang Ming Xu Cato Brede Jan Petter Larsen Simon Geir M?ller 《The Journal of biological chemistry》2013,288(31):22809-22820
The progressive loss of motor control due to reduction of dopamine-producing neurons in the substantia nigra pars compacta and decreased striatal dopamine levels are the classically described features of Parkinson disease (PD). Neuronal damage also progresses to other regions of the brain, and additional non-motor dysfunctions are common. Accumulation of environmental toxins, such as pesticides and metals, are suggested risk factors for the development of typical late onset PD, although genetic factors seem to be substantial in early onset cases. Mutations of DJ-1 are known to cause a form of recessive early onset Parkinson disease, highlighting an important functional role for DJ-1 in early disease prevention. This study identifies human DJ-1 as a metal-binding protein able to evidently bind copper as well as toxic mercury ions in vitro. The study further characterizes the cytoprotective function of DJ-1 and PD-mutated variants of DJ-1 with respect to induced metal cytotoxicity. The results show that expression of DJ-1 enhances the cells'' protective mechanisms against induced metal toxicity and that this protection is lost for DJ-1 PD mutations A104T and D149A. The study also shows that oxidation site-mutated DJ-1 C106A retains its ability to protect cells. We also show that concomitant addition of dopamine exposure sensitizes cells to metal-induced cytotoxicity. We also confirm that redox-active dopamine adducts enhance metal-catalyzed oxidation of intracellular proteins in vivo by use of live cell imaging of redox-sensitive S3roGFP. The study indicates that even a small genetic alteration can sensitize cells to metal-induced cell death, a finding that may revive the interest in exogenous factors in the etiology of PD. 相似文献