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91.
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Postural instability is one of the most incapacitating symptoms of Parkinson’s disease (PD) and appears to be related to cognitive deficits. This study aims to determine the cognitive factors that can predict deficits in static and dynamic balance in individuals with PD. A sociodemographic questionnaire characterized 52 individuals with PD for this work. The Trail Making Test, Rule Shift Cards Test, and Digit Span Test assessed the executive functions. The static balance was assessed using a plantar pressure platform, and dynamic balance was based on the Timed Up and Go Test. The results were statistically analysed using SPSS Statistics software through linear regression analysis. The results show that a statistically significant model based on cognitive outcomes was able to explain the variance of motor variables. Also, the explanatory value of the model tended to increase with the addition of individual and clinical variables, although the resulting model was not statistically significant The model explained 25–29% of the variability of the Timed Up and Go Test, while for the anteroposterior displacement it was 23–34%, and for the mediolateral displacement it was 24–39%. From the findings, we conclude that the cognitive performance, especially the executive functions, is a predictor of balance deficit in individuals with PD. 相似文献
93.
Genetic and paleomodelling evidence of the population expansion of the cattle egret Bubulcus ibis in Africa during the climatic oscillations of the Late Pleistocene 下载免费PDF全文
Carlos Congrains Antônio F. Carvalho Elder A. Miranda Graeme S. Cumming Dominic A. W. Henry Shiiwua A. Manu Jacinta Abalaka Cristiano D. Rocha Moussa S. Diop Joãozinho Sá Hamilton Monteiro Lars H. Holbech Francis Gbogbo Silvia N. Del Lama 《Journal of avian biology》2016,47(6):846-857
Increasing aridity during glacial periods produced the retraction of forests and the expansion of arid and semi‐arid environments in Africa, with consequences for birds. Cattle egret Bubulcus ibis is a dispersive species that prefers semi‐arid environments and requires proximity to bodies of water. We expected that climatic oscillations led to the expansion of the range of the cattle egret during arid periods, such as the Last Maximum Glacial (LGM) and contraction of distribution during the Last Interglacial (LIG) period, resulting in contact of populations previously isolated. We investigated this hypothesis by evaluating the genetic structure and population history of 15 cattle egret breeding colonies located in west and South Africa using the mitochondrial DNA (mtDNA) control region, mtDNA ATPase 8 and 6, and an intron of nuclear gene transforming growth factor‐beta 2. Occurrence data and bioclimatic information were used to generate ecological niche models of three periods (present, LGM and LIG). We used the genetic and paleomodelling data to assess the responses of the cattle egret from Africa to the climatic oscillations during the late Pleistocene. Genetic data revealed low levels of genetic differentiation, signs of isolation‐by‐distance, as well as recent increases in effective population size that started during the LGM. The observed low genetic structure may be explained by recent colonization events due to the demographic expansion following the last glacial period and by dispersal capacity of this species. The paleomodels corroborated the expansion during the LGM, and a more restricted potential distribution during the LIG. Our findinds supports the hypothesis that the species range of the cattle egret expanded during arid periods and contracted during wet periods. 相似文献
94.
Cristiane Lenz Dalla Corte Angélica Ramos Clarissa Marques Moreira dos Santos Valderi Luiz Dressler João Batista Teixeira da Rocha 《Biometals》2016,29(3):543-550
Organoseleno-compounds have been investigated for its beneficial effects against methylmercury toxicity. In this way, diphenyl diselenide (PhSe)2 was demonstrated to decrease Hg accumulation in mice, protect against MeHg-induced mitochondrial dysfunction, and protect against the overall toxicity of this metal. In the present study we aimed to investigate if co-treatment with (PhSe)2 and MeHg could decrease accumulation of Hg in liver slices of rats. Rat liver slices were co-treated with (PhSe)2 (0.5; 5 µM) and/or MeHg (25 µM) for 30 min at 37 °C and Se and Hg levels were measured by inductively coupled plasma mass spectrometry (ICP-MS) in the slices homogenate, P1 fraction, mitochondria and incubation medium. Co-treatment with (PhSe)2 and MeHg did not significantly alter Se levels in any of the samples when compared with compounds alone. In addition, co-treatment with (PhSe)2 and MeHg did not decrease Hg levels in any of the samples tested, although, co-incubation significantly increased Hg levels in homogenate. We suggest here that (PhSe)2 could exert its previously demonstrated protective effects not by reducing MeHg levels, but forming a complex with MeHg avoiding it to bind to critical molecules in cell. 相似文献
95.
Guilherme Rocha Melo Gondim Fabiana Baroni Alves Makdissi Ricardo Cesar Fogaroli Juan Bautista Donoso Collins Hirofumi Iyeyasu Douglas Guedes de Castro Maria Letícia Gobo Silva Michael Jenwei Chen Tharcisio Machado Coelho Henderson Ramos Antônio Cássio Assis Pellizzon 《Reports of Practical Oncology and Radiotherapy》2019,24(6):551-555
BackgroundWhole breast irradiation reduces loco-regional recurrence and risk of death in patients submitted to breast-conserving treatment. Data show that radiation to the index quadrant alone may be enough in selected patients.AimTo report the experience with intra-operative radiotherapy (IORT) with Electron-beam Cone in Linear Accelerator (ELIOT) and the results in overall survival, local control and late toxicity of patients submitted to this treatment.Materials and Methods147 patients treated with a median follow up of 6.9 years (0.1?11.5 years). The actuarial local control and overall survival probabilities were estimated using the Kaplan Meier method. All tests were two-sided and p ? 0.05 was considered statistically significant.ResultsOverall survival of the cohort in 5 years, in the median follow up and in 10 years was of 98.3%, 95.1% and 95.1%, respectively, whereas local control in 5 years, in the median follow up and in 10 years was of 96%, 94.9% and 89.5%, respectively. Two risk groups were identified for local recurrence depending on the estrogen or progesterone receptors, axillary or margin status and lymphovascular invasion (LVI) (p = 0.016).ConclusionsIORT is a safe and effective treatment. Rigorous selection is important to achieve excellent local control results. 相似文献
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97.
Amin Soltangheisi Paul J. A. Withers Paulo Sergio Pavinato Maurício Roberto Cherubin Raffaella Rossetto Janaina Braga Do Carmo Gustavo Casoni da Rocha Luiz Antonio Martinelli 《Global Change Biology Bioenergy》2019,11(12):1444-1455
Phosphorus (P) use in global food and bioenergy production needs to become more efficient and sustainable to reduce environmental impacts and conserve a finite and critical resource (Carpenter & Bennett, Environmental Research Letters, 2011, 6, 014009; Springmann et al., Nature, 2018, 562, 519). Sugarcane is one crop with a large P footprint because production is centered on P‐fixing soils with low P availability (Roy et al., Nature Plants, 2016, 2, 16043; Withers et al., Scientific Reports, 2018, 8, 2537). As global demand for processed sugar and bioethanol continues to increase, we advocate that improving P efficiency could become a key sustainability goal for the sugarcane industry. Here, we applied the 5R global P stewardship framework (Withers et al., Ambio, 2015, 44, 193) to identify more sustainable options to manage P in Brazilian sugarcane production. We show that current inputs of P fertilizer to the current crop area could be reduced by over 305 Gg, or 63%, over the next three decades by reducing unnecessary P fertilizer use, better utilization of recyclable bioresources and redesigning recommendation systems. Adoption of these 5R options would save the sugarcane industry in Brazil 528 US$ million and help safeguard global food and energy security. 相似文献
98.
I. Castro J. Rocha C. Costa G. Costa R. Ramírez-Rodríguez F. Amich 《Plant biosystems》2019,153(3):417-426
The morpho–environmental similarity between subsections Natrix and Viscosae has been pointed out as the reason for the genetic complexity of these groups of taxa. Based on this characterization a question emerges: could a very recent ongoing evolutionary process explain that morpho–environmental similarity? ISSR and cpSSR amplifications for 45 specimens belonging to taxa of Natrix and Viscosae subsections were developed, along their biogeographic distribution areas. Twenty-nine haplotypes were detected in the biogeographic area of both subsections, 79% were exclusive haplotypes, but the rest is shared between subsections Natrix and Viscosae species. Could that haplotype sharing be the result of potential hybridization between these taxa? Do current environmental conditions restrict the gene flow among taxa? The combination of ancestral genetic polymorphism, introgression, coalescence processes and periodic restricted environments (PRE) by glacial–interglacial environmental dynamics were discussed to explain the relevant percentage of exclusive haplotypes detected, as well as the persistence of shared haplotypes. These results are in accordance with the morpho–environmental proximity previously described for both subsections. 相似文献
99.
Rita Rocha Celso M. Teixeira-Duarte João M.P. Jorge João Henrique Morais-Cabral 《Journal of structural biology》2019,205(3):34-43
RCK (regulating conductance of K+) domains are common regulatory domains that control the activity of eukaryotic and prokaryotic K+ channels and transporters. In bacteria these domains play roles in osmoregulation, regulation of turgor and membrane potential and in pH homeostasis. Whole-genome sequencing unveiled RCK gene redundancy, however the biological role of this redundancy is not well understood. In Bacillus subtilis, there are two closely related RCK domain proteins (KtrA and KtrC) that regulate the activity of the Ktr cation channels. KtrA has been well characterized but little is known about KtrC. We have characterized the structural and biochemical proprieties of KtrC and conclude that KtrC binds ATP and ADP, just like KtrA. However, in solution KtrC exist in a dynamic equilibrium between octamers and non-octameric species that is dependent on the bound ligand, with ATP destabilizing the octameric ring relative to ADP. Accordingly, KtrC-ADP crystal structures reveal closed octameric rings similar to those in KtrA, while KtrC-ATP adopts an open assembly with RCK domains forming a super-helix. In addition, both KtrC-ATP and -ADP octamers are stabilized by the signaling molecule cyclic-di-AMP, which binds to KtrC with high affinity. In contrast, c-di-AMP binds with 100-fold lower affinity to KtrA. Despite these differences we show with an E. coli complementation assay that KtrC and KtrA are interchangeable and able to form functional transporters with both KtrB and KtrD. The distinctive properties of KtrC, in particular ligand-dependent assembly/disassembly, suggest that this protein has a specific physiological role that is distinct from KtrA. 相似文献
100.
Bingxin Wang Daniel G. Rocha Mark I. Abrahams Andr P. Antunes Hugo C. M. Costa Andr Luis Sousa Gonalves Wilson Roberto Spironello Milton Jos de Paula Carlos A. Peres Juarez Pezzuti Emiliano Ramalho Marcelo Lima Reis Elildo Carvalho Jr Fabio Rohe David W. Macdonald Cedric Kai Wei Tan 《Ecology and evolution》2019,9(9):5049-5062
Amazonia forest plays a major role in providing ecosystem services for human and sanctuaries for wildlife. However, ongoing deforestation and habitat fragmentation in the Brazilian Amazon has threatened both. The ocelot is an ecologically important mesopredator and a potential conservation ambassador species, yet there are no previous studies on its habitat preference and spatial patterns in this biome. From 2010 to 2017, twelve sites were surveyed, totaling 899 camera trap stations, the largest known dataset for this species. Using occupancy modeling incorporating spatial autocorrelation, we assessed habitat use for ocelot populations across the Brazilian Amazon. Our results revealed a positive sigmoidal correlation between remote‐sensing derived metrics of forest cover, disjunct core area density, elevation, distance to roads, distance to settlements and habitat use, and that habitat use by ocelots was negatively associated with slope and distance to river/lake. These findings shed light on the regional scale habitat use of ocelots and indicate important species–habitat relationships, thus providing valuable information for conservation management and land‐use planning. 相似文献