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901.
902.
Laura Roesler Nery Natalia Silva Eltz Cristiana Hackman Raphaela Fonseca Stefani Altenhofen Heydi Noriega Guerra Vanessa Morais Freitas Carla Denise Bonan Monica Ryff Moreira Roca Vianna 《PloS one》2014,9(9)
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder with no effective treatment and commonly diagnosed only on late stages. Amyloid-β (Aβ) accumulation and exacerbated tau phosphorylation are molecular hallmarks of AD implicated in cognitive deficits and synaptic and neuronal loss. The Aβ and tau connection is beginning to be elucidated and attributed to interaction with different components of common signaling pathways. Recent evidences suggest that non-fibrillary Aβ forms bind to membrane receptors and modulate GSK-3β activity, which in turn phosphorylates the microtubule-associated tau protein leading to axonal disruption and toxic accumulation. Available AD animal models, ranging from rodent to invertebrates, significantly contributed to our current knowledge, but complementary platforms for mechanistic and candidate drug screenings remain critical for the identification of early stage biomarkers and potential disease-modifying therapies. Here we show that Aβ1–42 injection in the hindbrain ventricle of 24 hpf zebrafish embryos results in specific cognitive deficits and increased tau phosphorylation in GSK-3β target residues at 5dpf larvae. These effects are reversed by lithium incubation and not accompanied by apoptotic markers. We believe this may represent a straightforward platform useful to identification of cellular and molecular mechanisms of early stage AD-like symptoms and the effects of neuroactive molecules in pharmacological screenings. 相似文献
903.
The nucleotide sequence of the tcpC gene has been determined. It encodes a 53995-Da protein precursor with a signal sequence and cleavage site typical of a number of outer membrane lipoproteins, which are cleaved by the equivalent of signal peptidase II (Lsp) of Escherichia coli. The location of the tcpC gene is such that it is predicted to be translationally coupled to the 5' and 3' flanking genes, tcpY and tcpD, respectively, indicating that it forms part of an operon. Together with the lipoprotein signal sequence and the several hydrophobic domains it seems likely that TcpC is a surface-anchored trans-outer membrane lipoprotein. 相似文献
904.
Edith Calixto-Pérez Jesús Alarcón-Guerrero Gabriel Ramos-Fernández Pedro Américo D. Dias Ariadna Rangel-Negrín Monica Améndola-Pimenta Cristina Domingo Víctor Arroyo-Rodríguez Gilberto Pozo-Montuy Braulio Pinacho-Guendulain Tania Urquiza-Haas Patricia Koleff Enrique Martínez-Meyer 《Primates; journal of primatology》2018,59(5):451-467
Ecological niche modeling is used to estimate species distributions based on occurrence records and environmental variables, but it seldom includes explicit biotic or historical factors that are important in determining the distribution of species. Expert knowledge can provide additional valuable information regarding ecological or historical attributes of species, but the influence of integrating this information in the modeling process has been poorly explored. Here, we integrated expert knowledge in different stages of the niche modeling process to improve the representation of the actual geographic distributions of Mexican primates (Ateles geoffroyi, Alouatta pigra, and A. palliata mexicana). We designed an elicitation process to acquire information from experts and such information was integrated by an iterative process that consisted of reviews of input data by experts, production of ecological niche models (ENMs), and evaluation of model outputs to provide feedback. We built ENMs using the maximum entropy algorithm along with a dataset of occurrence records gathered from a public source and records provided by the experts. Models without expert knowledge were also built for comparison, and both models, with and without expert knowledge, were evaluated using four validation metrics that provide a measure of accuracy for presence-absence predictions (specificity, sensitivity, kappa, true skill statistic). Integrating expert knowledge to build ENMs produced better results for potential distributions than models without expert knowledge, but a much greater improvement in the transition from potential to realized geographic distributions by reducing overprediction, resulting in better representations of the actual geographic distributions of species. Furthermore, with the combination of niche models and expert knowledge we were able to identify an area of sympatry between A. palliata mexicana and A. pigra. We argue that the inclusion of expert knowledge at different stages in the construction of niche models in an explicit and systematic fashion is a recommended practice as it produces overall positive results for representing realized species distributions. 相似文献
905.
Utility of ninhydrin reagent for spectrofluorimetric determination of heptaminol in human plasma
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For the determination of heptaminol (HEP) in its authentic and dosage form as well as in human plasma, a new simple, sensitive and cheap fluorimetric method of analysis was developed and validated. The presented method is based on the reaction between aliphatic primary amino moiety present in HEP with ninhydrin and phenylacetaldehyde using Torell and Stenhagen buffer at pH 8.2 that yields a highly fluorescent derivative which after excitation at 390 nm showed a fluorescence emission at 464 nm. The effects of various experimental factors on both the development and stability of the fluorescent product was evaluated and optimized. In the concentration range (0.5–6.0 μg/ml), the constructed calibration curve was linear with a good correlation coefficient (0.9997) and the calculated limit of detection (LOD) and limit of quantitation (LOQ) were 0.14 and 0.43 respectively. The presented method was successfully applied for determination of Corasore® tablets and validated according to ICH guidelines. 相似文献
906.
Yogendra Khedikar Manish K. Pandey V. Sujay Sube Singh Spurthi N. Nayak Henry W. Klein-Gebbinck Cholin Sarvamangala Ganapati Mukri Vanika Garg Hari D. Upadhyaya H. L. Nadaf M. V. C. Gowda Rajeev K. Varshney Ramesh S. Bhat 《Molecular breeding : new strategies in plant improvement》2018,38(1):7
An effort was made in the present study to identify the main effect and epistatic quantitative trait locus (QTL) for the morphological and yield-related traits in peanut. A recombinant inbred line (RIL) population derived from TAG 24 × GPBD 4 was phenotyped in seven environments at two locations. QTL analysis with available genetic map identified 62 main-effect QTLs (M-QTLs) for ten morphological and yield-related traits with the phenotypic variance explained (PVE) of 3.84–15.06%. Six major QTLs (PVE >?10%) were detected for PLHT, PPP, YPP, and SLNG. Stable M-QTLs appearing in at least two environments were detected for PLHT, LLN, YPP, YKGH, and HSW. Five M-QTLs governed two traits each, and 16 genomic regions showed co-localization of two to four M-QTLs. Intriguingly, a major QTL reported to be linked to rust resistance showed pleiotropic effect for yield-attributing traits like YPP (15.06%, PVE) and SLNG (13.40%, PVE). Of the 24 epistatic interactions identified across the traits, five interactions involved six M-QTLs. Three interactions were additive × additive and remaining two involved QTL × environment (QE) interactions. Only one major M-QTL governing PLHT showed epistatic interaction. Overall, this study identified the major M-QTLs for the important productivity traits and also described the lack of epistatic interactions for majority of them so that they can be conveniently employed in peanut breeding. 相似文献
907.
908.
P. Garg R. Aziz T. Al Musa D. P. Ripley P. Haaf J. R. J. Foley P. P. Swoboda G. J. Fent L. E. Dobson J. P. Greenwood S. Plein 《Netherlands heart journal》2018,26(2):85-93
Aims
Myocardial perfusion imaging during hyperaemic stress is commonly used to detect coronary artery disease. The aim of this study was to investigate the relationship between left ventricular global longitudinal strain (GLS), strain rate (GLSR), myocardial early (E’) and late diastolic velocities (A’) with adenosine stress first-pass perfusion cardiovascular magnetic resonance (CMR) imaging.Methods and results
44 patients met the inclusion criteria and underwent CMR imaging. The CMR imaging protocol included: rest/stress horizontal long-axis (HLA) cine, rest/stress first-pass adenosine perfusion and late gadolinium enhancement imaging. Rest and stress HLA cine CMR images were analysed using feature-tracking software for the assessment of myocardial deformation. The presence of perfusion defects was scored on a binomial scale. In patients with hyperaemia-induced perfusion defects, rest global longitudinal strain GLS (?16.9 ± 3.7 vs. ?19.6 ± 3.4; p-value = 0.02), E’ (?86 ± 22 vs. ?109 ± 38; p-value = 0.02), GLSR (69 ± 31 vs. 93 ± 38; p-value = 0.01) and stress GLS (?16.5 ± 4 vs. ?21 ± 3.1; p < 0.001) were significantly reduced when compared with patients with no perfusion defects. Stress GLS was the strongest independent predictor of perfusion defects (odds ratio 1.43 95% confidence interval 1.14–1.78, p-value <0.001). A threshold of ?19.8% for stress GLS demonstrated 78% sensitivity and 73% specificity for the presence of hyperaemia-induced perfusion defects.Conclusions
At peak myocardial hyperaemic stress, GLS is reduced in the presence of a perfusion defect in patients with suspected coronary artery disease. This reduction is most likely caused by reduced endocardial blood flow at maximal hyperaemia because of transmural redistribution of blood flow in the presence of significant coronary stenosis.909.
910.
Gunjal Garg Ali Yilmaz Praveen Kumar Onur Turkoglu David G. Mutch Matthew A. Powell Barry Rosen Ray O. Bahado-Singh Stewart F. Graham 《Metabolomics : Official journal of the Metabolomic Society》2018,14(12):154