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961.
An evolutionary tolerance model explaining spatial patterns in species richness under environmental gradients and geometric constraints 总被引:1,自引:0,他引:1
In this study, we developed a simulation model based on the ecological and evolutionary dynamics of geographical ranges, to understand the role of species' environmental tolerances and the strength of the environmental gradient in determining spatial patterns in species richness. Using an one-dimensional space, we present the model and dissect its parameters. Also, we test the ability of the model to simulate richness in complex two-dimensional domains and to fit real patterns in species richness, using South American Tyrannidae as an example. We found that a mid-spatial peak in species richness arises spontaneously under conditions of high environmental tolerances and/or a weak environmental gradient, since this condition causes wide species' geographic ranges, which are constrained by domain's boundary and tend to overlap in the middle. Our model was also a good predictor of real patterns in species richness, especially under conditions of high environmental strength and small species' tolerance. We conclude that this kind of spatial simulation models based on species' physiological tolerance may be an important tool to understand the evolutionary dynamics of species' geographic ranges and in spatial patterns of species richness. 相似文献
962.
Juliane Guimar?es Carvalho Aline de Lima Leite Camila Peres-Buzalaf Fernanda Salvato Carlos Alberto Labate Eric T. Everett Gary Milton Whitford Marília Afonso Rabelo Buzalaf 《PloS one》2013,8(1)
A/J and 129P3/J mouse strains have different susceptibilities to dental fluorosis due to their genetic backgrounds. They also differ with respect to several features of fluoride (F) metabolism and metabolic handling of water. This study was done to determine whether differences in F metabolism could be explained by diversities in the profile of protein expression in kidneys. Weanling, male A/J mice (susceptible to dental fluorosis, n = 18) and 129P3/J mice (resistant, n = 18) were housed in pairs and assigned to three groups given low-F food and drinking water containing 0, 10 or 50 ppm [F] for 7 weeks. Renal proteome profiles were examined using 2D-PAGE and LC-MS/MS. Quantitative intensity analysis detected between A/J and 129P3/J strains 122, 126 and 134 spots differentially expressed in the groups receiving 0, 10 and 50 ppmF, respectively. From these, 25, 30 and 32, respectively, were successfully identified. Most of the proteins were related to metabolic and cellular processes, followed by response to stimuli, development and regulation of cellular processes. In F-treated groups, PDZK-1, a protein involved in the regulation of renal tubular reabsorption capacity was down-modulated in the kidney of 129P3/J mice. A/J and 129P3/J mice exhibited 11 and 3 exclusive proteins, respectively, regardless of F exposure. In conclusion, proteomic analysis was able to identify proteins potentially involved in metabolic handling of F and water that are differentially expressed or even not expressed in the strains evaluated. This can contribute to understanding the molecular mechanisms underlying genetic susceptibility to dental fluorosis, by indicating key-proteins that should be better addressed in future studies. 相似文献
963.
Daniela Leite Jabes Ana Claudia de Freitas Oliveira Valquíria Campos Alencar Fabiano Bezerra Menegidio Débora Liliane Souza Reno Daiene Souza Santos David Aciole Barbosa Renata Ozelami Vilas Boas Rodrigo Luiz de Oliveira Rodrigues Cunha Tiago Rodrigues Regina Costa de Oliveira Luiz R. Nunes 《Molecular genetics and genomics : MGG》2016,291(3):1347-1362
964.
Fortini Evandro Alexandre Batista Diego Silva de Castro Kamila Motta Silva Tatiane Dulcineia Felipe Sérgio Heitor Sousa Correia Ludmila Nayara Freitas Chagas Kristhiano Farias Letícia Monteiro Leite João Paulo Viana Otoni Wagner Campos 《Plant Cell, Tissue and Organ Culture》2020,142(3):595-611
Plant Cell, Tissue and Organ Culture (PCTOC) - Photoperiod regulates different morphophysiological processes in plants, directly impacting photosynthetic performance and, consequently, primary and... 相似文献
965.
966.
967.
Renato Chaves Souto Branco Rafael Ludemann Camargo Thiago Martins Batista Jean Franciesco Vettorazzi Camila Lubaczeuski Lucas Henrique Montes Bomfim Leonardo Reis Silveira Antônio Carlos Boschero Cláudio Cesar Zoppi Everardo Magalhães Carneiro 《Journal of cellular physiology》2019,234(5):6313-6323
Nutrient malnutrition, during the early stages of development, may facilitate the onset of metabolic diseases later in life. However, the consequences of nutritional insults, such as a high-fat diet (HFD) after protein restriction, are still controversial. We assessed overall glucose homeostasis and molecular markers of mitochondrial function in the gastrocnemius muscle of protein-restricted mice fed an HFD until early adulthood. Male C57BL/6 mice were fed a control (14% protein-control diet) or a protein-restricted (6% protein-restricted diet) diet for 6 weeks. Afterward, mice received an HFD or not for 8 weeks (mice fed a control diet and HFD [CH] and mice fed a protein-restricted diet and HFD [RH]). RH mice showed lower weight gain and fat accumulation and did not show an increase in fasting plasma glucose and insulin levels compared with CH mice. RH mice showed higher energy expenditure, increased citrate synthase, peroxisome-proliferator-activated receptor gamma coactivator 1-alpha protein content, and higher levels of malate and α-ketoglutarate compared with CH mice. Moreover, RH mice showed increased AMPc-dependent kinase and acetyl coenzyme-A (CoA) carboxylase phosphorylation, lower intramuscular triacylglycerol content, and similar malonyl-CoA levels. In conclusion, protein undernourishment after weaning does not potentiate fat accumulation and insulin resistance in adult young mice fed an HFD. This outcome seems to be associated with increased skeletal muscle mitochondrial oxidative capacity and reduced lipids accumulation. 相似文献
968.
Lacerda Filho Armando Marsden Cavalcante Cecília Menelau Da Silva Andrey Batista Inácio Cicero Pinheiro de Lima-Neto Reginaldo Gonçalves de Andrade Melyna Chaves Leite Magalhães Oliane Maria Correia dos Santos Franz de Assis Graciano Neves Rejane Pereira 《Mycopathologia》2019,184(4):547-549
Mycopathologia - The article describes an atypical case of cat-transmitted ocular sporotrichosis due Sporothrix brasiliensis in a young patient. This report contributes significantly to knowledge... 相似文献
969.
Juliana M. M. Angheben Guus H. M. Schoorlemmer Marcio V. Rossi Thiago A. Silva Sergio L. Cravo 《PloS one》2014,9(1)
Spontaneously hypertensive rats (SHR), like patients with sleep apnea, have hypertension, increased sympathetic activity, and increased chemoreceptor drive. We investigated the role of carotid chemoreceptors in cardiovascular responses induced by obstructive apnea in awake SHR. A tracheal balloon and vascular cannulas were implanted, and a week later, apneas of 15 s each were induced. The effects of apnea were more pronounced in SHR than in control rats (Wistar Kyoto; WKY). Blood pressure increased by 57±3 mmHg during apnea in SHR and by 28±3 mmHg in WKY (p<0.05, n = 14/13). The respiratory effort increased by 53±6 mmHg in SHR and by 34±5 mmHg in WKY. The heart rate fell by 209±19 bpm in SHR and by 155±16 bpm in WKY. The carotid chemoreceptors were then inactivated by the ligation of the carotid body artery, and apneas were induced two days later. The inactivation of chemoreceptors reduced the responses to apnea and abolished the difference between SHR and controls. The apnea-induced hypertension was 11±4 mmHg in SHR and 8±4 mmHg in WKY. The respiratory effort was 15±2 mmHg in SHR and 15±2 mmHg in WKY. The heart rate fell 63±18 bpm in SHR and 52±14 bpm in WKY. Similarly, when the chemoreceptors were unloaded by the administration of 100% oxygen, the responses to apnea were reduced. In conclusion, arterial chemoreceptors contribute to the responses induced by apnea in both strains, but they are more important in SHR and account for the exaggerated responses of this strain to apnea. 相似文献
970.
Patricia Postilione Appolinário Danilo Bilches Medinas Adriano B. Chaves-Filho Thiago C. Genaro-Mattos José Renato Rosa Cussiol Luis Eduardo Soares Netto Ohara Augusto Sayuri Miyamoto 《PloS one》2015,10(4)
Docosahexaenoic acid (C22:6, n-3, DHA) is a polyunsaturated fatty acid highly enriched in the brain. This fatty acid can be easily oxidized yielding hydroperoxides as primary products. Cu, Zn-Superoxide dismutase (SOD1) aggregation is a common hallmark of Amyotrophic Lateral Sclerosis (ALS) and the molecular mechanisms behind their formation are not completely understood. Here we investigated the effect of DHA and its hydroperoxides (DHAOOH) on human SOD1 oligomerization in vitro. DHA induced the formation of high-molecular-weight (HMW) SOD1 species (>700 kDa). Aggregation was dependent on free thiols and occurred primarily with the protein in its apo-form. SOD1 incubation with DHA was accompanied by changes in protein structure leading to exposure of protein hydrophobic patches and formation of non-amyloid aggregates. Site-directed mutagenesis studies demonstrated that Cys 6 and Cys 111 in wild-type and Cys 6 in ALS-linked G93A mutant are required for aggregation. In contrast, DHAOOH did not induce HMW species formation but promoted abnormal covalent dimerization of apo-SOD1 that was resistant to SDS and thiol reductants. Overall, our data demonstrate that DHA and DHAOOH induce distinct types of apo-SOD1 oligomerization leading to the formation of HMW and low-molecular-weight species, respectively. 相似文献