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11.
Gabriela de Lima Menezes Ricardo Lemes Gonçalves Raisa Melo Lima Maristela Pereira Marcos Lázaro Moreli 《Journal of biomolecular structure & dynamics》2020,38(17):5277-5286
Communicated by Ramaswamy H. Sarma 相似文献
12.
Rodolpho Santos Telles Menezes Thiago Magalhães Silva Antônio Freire Carvalho Vanderly Andrade-Souza Janisete Gomes Silva Marco Antonio Costa 《Genetica》2013,141(7-9):273-280
The Neotropical Polistinae wasps are diverse in taxonomy, social behavior, and nesting founding characteristics. Although some species in this group have been used as models for studies on wasp’s biology, they are poorly known in terms of cytogenetics. Here we reported an intraspecific numerical-structural chromosome variation in the swarm-founding wasp Metapolybia decorata from the Brazilian Atlantic Rainforest using conventional and molecular cytogenetic techniques. The observed structural chromosome change involved a telomeric fusion that resulted in a chromosome number range of 2n = 34–36. The origin and geographic distribution of the variant chromosome forms as well as their frequency and maintenance in the studied populations are discussed. In addition, we reported a novel and geographically restricted deletion in the fused chromosomes indicating that the species is undergoing a continued process of karyotype evolution leading to fused chromosome stabilization by elimination of inactive centromeric sequences. Evidence of differences in the telomeric sequences of this wasp was also found by in situ hybridization using the motif (T2AG2)7 as probe. 相似文献
13.
Parathyroidectomy Improves Survival In Patients with Severe Hyperparathyroidism: A Comparative Study
Patricia Taschner Goldenstein Rosilene Motta Elias Lilian Pires de Freitas do Carmo Fernanda Oliveira Coelho Luciene Pereira Magalh?es Gisele Lins Antunes Melani Ribeiro Custódio Fábio Luiz de Menezes Montenegro Silvia Maria Titan Vanda Jorgetti Rosa Maria Affonso Moysés 《PloS one》2013,8(8)
Background and objectives
Secondary hyperparathyroidism (SHPT) in CKD is associated with an increased risk for mortality, but definitive data showing that parathormone control decreases mortality is still lacking. This study aimed to compare the mortality of patients with severe SHPT submitted to parathyroidectomy(PTX) with those who did not have access to surgery.Methods
This is a retrospective study in a cohort of 251 CKD patients with severe SHPT who were referred to a CKD-MBD Center for PTX from 2005 until 2012.Results
Most of our patients had indication of PTX, but only 49% of them had access to this surgical procedure. After a mean follow-up of 23 months, 72 patients had died. Non-survivors were older; more often had diabetes, lower serum 25 vitamin D and mostly had not been submitted to surgery. The relative risk of death was lower in the PTX patients (0.428; 95% CI, 0.28 to 0.67; p<0.0001). After adjustments, mortality risk was dependent on age (1.04; 95% CI, 1.01 to 1.07; p = 0.002), 25 vitamin D (0.43; 95% CI, 0.24 to 0.81; p = 0.006) and no access to PTX (4.13; 95% CI, 2.16 to 7.88; p<0.0001). Results remained the same in a second model using the PTX date as the study start date for the PTX group.Conclusions
Our data confirms the benefit of PTX on mortality in patients with severe SHPT. The high mortality encountered in our population is significant and urges the need to better treat these patients. 相似文献14.
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16.
Rafael Silva Menezes Aline Terra Soares Jair Gonzalez Marques Júnior Rafael Garcia Lopes Rafael Fonseca da Arantes Roberto Bianchini Derner Nelson Roberto Antoniosi Filho 《Journal of applied phycology》2016,28(5):2679-2686
The purposes of this study were to assess the influence of culture medium on biomass production, fatty acid, and pigment composition of Choricystis minor var. minor and to evaluate the use of this microalga as a source of fatty raw material for biodiesel production. Cultures of C. minor var. minor were grown using WC (Wright’s cryptophyte) and BBM (Bold’s Basal medium) media. BBM medium produced more biomass (984.3 mg L?1) compared to the WC medium (525.7 mg L?1). Despite this result, WC medium produced a higher methyl ester yield for biodiesel production than the BBM medium (170.0 and 90.2 mg g?1 of biomass, respectively). The average percentage of fatty acids obtained using the WC medium (17.0 %) was similar to soybean (18.0 %) and with similar biomass fatty acid profile. However, for pigment production, carotenoids and chlorophyll concentrations were twice as high when using the BBM medium. 相似文献
17.
Paulo Eduardo Menezes‐Silva Lucas Loram‐Loureno Rauander Douglas Ferreira Barros Alves Letícia Ferreira Sousa Sabrina Emanuella da Silva Almeida Fernanda Santos Farnese 《Ecology and evolution》2019,9(20):11979-11999
Anthropogenic activities such as uncontrolled deforestation and increasing greenhouse gas emissions are responsible for triggering a series of environmental imbalances that affect the Earth's complex climate dynamics. As a consequence of these changes, several climate models forecast an intensification of extreme weather events over the upcoming decades, including heat waves and increasingly severe drought and flood episodes. The occurrence of such extreme weather will prompt profound changes in several plant communities, resulting in massive forest dieback events that can trigger a massive loss of biodiversity in several biomes worldwide. Despite the gravity of the situation, our knowledge regarding how extreme weather events can undermine the performance, survival, and distribution of forest species remains very fragmented. Therefore, the present review aimed to provide a broad and integrated perspective of the main biochemical, physiological, and morpho‐anatomical disorders that may compromise the performance and survival of forest species exposed to climate change factors, particularly drought, flooding, and global warming. In addition, we also discuss the controversial effects of high CO2 concentrations in enhancing plant growth and reducing the deleterious effects of some extreme climatic events. We conclude with a discussion about the possible effects that the factors associated with the climate change might have on species distribution and forest composition. 相似文献
18.
Corrêa Soares JB Maya-Monteiro CM Bittencourt-Cunha PR Atella GC Lara FA d'Avila JC Menezes D Vannier-Santos MA Oliveira PL Egan TJ Oliveira MF 《FEBS letters》2007,581(9):1742-1750
Hemozoin (Hz) is a heme crystal produced upon hemoglobin digestion as the main mechanism of heme disposal in several hematophagous organisms. Here, we show that, in the helminth Schistosoma mansoni, Hz formation occurs in extracellular lipid droplets (LDs). Transmission electron microscopy of adult worms revealed the presence of numerous electron-lucent round structures similar to LDs in gut lumen, where multicrystalline Hz assemblies were found associated to their surfaces. Female regurgitates promoted Hz formation in vitro in reactions partially inhibited by boiling. Fractionation of regurgitates showed that Hz crystallization activity was essentially concentrated on lower density fractions, which have small amounts of pre-formed Hz crystals, suggesting that hydrophilic-hydrophobic interfaces, and not Hz itself, play a key catalytic role in Hz formation in S. mansoni. Thus, these data demonstrate that LDs present in the gut lumen of S. mansoni support Hz formation possibly by allowing association of heme to the lipid-water interface of these structures. 相似文献
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20.
Maruyama Fernanda Harumi de Paula Daphine Ariadne Jesus Menezes Isabela de Godoy Favalessa Olívia Cometti Hahn Rosane Christine de Almeida Arleana do Bom Parto Ferreira Sousa Valéria Régia Franco Nakazato Luciano Dutra Valéria 《Mycopathologia》2019,184(1):45-51
Mycopathologia - Cryptococcosis is caused by fungi of the genus Cryptococcus. Owing to its importance, this study aimed to analyze the genetic diversity of C. gattii isolates from animals, humans,... 相似文献