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991.
Sara Santos de Carvalho Ana Cristina Sim?es e Silva Adriano de Paula Sabino Fernanda Cristina Gontijo Evangelista Karina Braga Gomes Luci Maria SantAna Dusse Danyelle Romana Alves Rios 《PloS one》2016,11(3)
Background
There is substantial evidence that chronic renal and cardiovascular diseases are associated with coagulation disorders, endothelial dysfunction, inflammation and fibrosis. Angiotensin-Converting Enzyme Insertion/Deletion polymorphism (ACE I/D polymorphism) has also be linked to cardiovascular diseases. Therefore, this study aimed to compare plasma levels of ultrassensible C-reactive protein (usCRP), PAI-1, D-dimer and TGF-β1 in patients undergoing HD with different ACE I/D polymorphisms.Methods
The study was performed in 138 patients at ESRD under hemodialysis therapy for more than six months. The patients were divided into three groups according to the genotype. Genomic DNA was extracted from blood cells (leukocytes). ACE I/D polymorphism was investigated by single polymerase chain reaction (PCR). Plasma levels of D-dimer, PAI-1 and TGF-β1 were measured by enzyme-linked immunosorbent assay (ELISA), and the determination of plasma levels of usCRP was performed by immunonephelometry. Data were analyzed by the software SigmaStat 2.03.Results
Clinical characteristics were similar in patients with these three ACE I/D polymorphisms, except for interdialytic weight gain. I allele could be associated with higher interdialytic weight gain (P = 0.017). Patients genotyped as DD and as ID had significantly higher levels of PAI-1 than those with II genotype. Other laboratory parameters did not significantly differ among the three subgroups (P = 0.033). Despite not reaching statistical significance, plasma levels of usCRP were higher in patients carrying the D allele.Conclusion
ACE I/D polymorphisms could be associated with changes in the regulation of sodium, fibrinolytic system, and possibly, inflammation. Our data showed that high levels of PAI-1 are detected when D allele is present, whereas greater interdialytic gain is associated with the presence of I allele. However, further studies with different experimental designs are necessary to elucidate the mechanisms involved in these associations. 相似文献992.
Fernanda Gabriela Bitencourt Wommer Everton Miguel Silva Loreto Lenira Maria Nunes Sepel 《Journal of biological education》2018,52(2):155-165
The history of science is an important component to acquire for achieving scientific literacy. In this study, a collaborative activity was applied in which the students were presented with the historical context in which Robert Hooke lived and developed the first register of the microscopic world. Furthermore, the students explored the environment using a microscope made by themselves, employing PET bottles and lenses obtained from CD or DVD readers and, finally, they drew and described selected objects, and collaboratively rewrote a ‘new version’ of Hooke’s classical book ‘Micrographia’. The study was performed in a secondary school, with 12- to 15-year-old students, and the hypothesis was that the planned intervention could enlarge students’ perception of historical aspects of the scientific discovery of the microscopic world, to a greater extent than traditional classes involving lectures and textbooks. The comparison was evaluated using a quantitative tool, called the History-Word-Association test (HWAT), which aims to evaluate the general vision of students regarding the agents, historical period and sociocultural circumstance involved in the issue addressed. The students that participated in the planned didactic activity showed a significant improvement in identification and retention of ideas associated with the history of the discovery of the microscopic world. 相似文献
993.
Paul A. Garber Christini B. Caselli Anna C. McKenney Filipa Abreu Maria Fernanda De la Fuente Arrilton Araújo Maria de Fatima Arruda Antonio Souto Nicola Schiel Júlio Csar Bicca‐Marques 《American journal of primatology》2019,81(7)
Understanding the set of factors that promote and constrain a species’ ability to exploit ecologically distinct habitats is central for addressing questions of intraspecific variability in behavior and morphology. In this study, we compared newly collected data with published data on body measurements, group size and composition, daily path length, home range, and reproductive output in wild common marmosets naturally inhabiting two contrasting environments in northeastern Brazil: the Atlantic Forest (AF), which is characterized by high biodiversity and reduced seasonality in food availability and the Caatinga (CAT), which is characterized by a severe hot and dry season lasting from 5 to 11 months, drought‐resistant plant species, and reduced primary productivity. Despite marked differences in ecological conditions, CAT marmosets and AF marmosets differed minimally in daily path length, home range, reproductive output, and infant survivorship. CAT marmosets were found to live in smaller groups containing fewer adult females than AF marmosets, and also were characterized by a greater surface area to body mass ratio, a trait that may represent an adaptation to the hot and dry conditions of the Caatinga. We propose that in conjunction with body mass reduction, minor adjustments in behavior, the exploitation of cacti as a source of water and nutrients, and access to exudates as a dependable year‐round food resource, common marmosets successfully used the same adaptive pattern to maintain high reproductive output and infant survivorship in exploiting these two ecologically distinct environments. 相似文献
994.
Mayara Sandrielly Pereira Soares Bruna da Silveira de Mattos Anita Almeida Ávila Luiza Spohr Nathalia Stark Pedra Fernanda Cardoso Teixeira Natália Pontes Bona Pathise Souto Oliveira Francieli Moro Stefanello Roselia Maria Spanevello 《Journal of cellular biochemistry》2019,120(2):2289-2303
We investigated acute and chronic effects administration of methionine (Met) and/or methionine sulfoxide (MetO) on ectonucleotidases and oxidative stress in platelets and serum of young rats. Wistar rats were divided into four groups: control, Met, MetO, and Met + MetO. In acute treatment, the animals received a single subcutaneous injection of amino acid(s) and were euthanized after 1 and 3 hours. In chronic protocol, Met and/or MetO were administered twice a day with an 8-hour interval from the 6th to the 28th day of life. Nucleoside triphosphate phosphohydrolase and 5′-nucleotidase activities were reduced in platelets and serum by Met, MetO, and Met + MetO after 3 hours and 21 days. Adenosine deaminase activity reduced in platelets at 3 hours after MetO and Met + MetO administration and increased after 21 days in animals treated with Met + MetO. Superoxide dismutase and catalase activities decreased in platelets in MetO and Met + MetO groups after 3 hours, while reactive oxygen species (ROS) levels increased in same groups. Catalase activity in platelets decreased in all experimental groups after chronic treatment. Met, MetO, and Met + MetO administration increased plasmatic ROS levels in acute and chronic protocols; glutathione S-transferase activity increased by MetO and Met + MetO administration at 3 hours, and ascorbic acid decreased in all experimental groups in acute and chronic protocols. Thiobarbituric acid reactive substances increased, superoxide dismutase and catalase activities reduced in the Met and/or MetO groups at 3 hours and in chronic treatment. Our data demonstrated that Met and/or MetO induced changes in adenine nucleotide hydrolysis and redox status of platelets and serum, which can be associated with platelet dysfunction in hypermethioninemia. 相似文献
995.
Octavio M. Palacios-Gimenez Carlos Roberto Carvalho Fernanda Aparecida Ferrari Soares Diogo C. Cabral-de-Mello 《PloS one》2015,10(12)
A large percentage of eukaryotic genomes consist of repetitive DNA that plays an important role in the organization, size and evolution. In the case of crickets, chromosomal variability has been found using classical cytogenetics, but almost no information concerning the organization of their repetitive DNAs is available. To better understand the chromosomal organization and diversification of repetitive DNAs in crickets, we studied the chromosomes of two Gryllidae species with highly divergent karyotypes, i.e., 2n(♂) = 29,X0 (Gryllus assimilis) and 2n = 9, neo-X1X2Y (Eneoptera surinamensis). The analyses were performed using classical cytogenetic techniques, repetitive DNA mapping and genome-size estimation. Conserved characteristics were observed, such as the occurrence of a small number of clusters of rDNAs and U snDNAs, in contrast to the multiple clusters/dispersal of the H3 histone genes. The positions of U2 snDNA and 18S rDNA are also conserved, being intermingled within the largest autosome. The distribution and base-pair composition of the heterochromatin and repetitive DNA pools of these organisms differed, suggesting reorganization. Although the microsatellite arrays had a similar distribution pattern, being dispersed along entire chromosomes, as has been observed in some grasshopper species, a band-like pattern was also observed in the E. surinamensis chromosomes, putatively due to their amplification and clustering. In addition to these differences, the genome of E. surinamensis is approximately 2.5 times larger than that of G. assimilis, which we hypothesize is due to the amplification of repetitive DNAs. Finally, we discuss the possible involvement of repetitive DNAs in the differentiation of the neo-sex chromosomes of E. surinamensis, as has been reported in other eukaryotic groups. This study provided an opportunity to explore the evolutionary dynamics of repetitive DNAs in two non-model species and will contribute to the understanding of chromosomal evolution in a group about which little chromosomal and genomic information is known. 相似文献
996.
997.
Adrian A. Spisso Soledad Cerutti Fernanda Silva Pablo H. Pacheco Luis D. Martinez 《Biometals》2014,27(3):591-599
An approach to understand vines (Vitis vinifera) defense mechanism against heavy metal stress by isolation and determination of Hg-phytochelatins (PCs) complexes was performed. PCs are important molecules involved in the control of metal concentration in plants. PCs complex toxic metals through ?SH groups and stores them inside cells vacuole avoiding any toxic effect of free metals in the cytosol. The Hg-PCs identification was achieved by determination of Hg and S as hetero-tagged atoms. A method involving two-dimensional chromatographic analysis coupled to atomic spectrometry and confirmation by tandem mass spectrometry is proposed. An approach involving size exclusion chromatography coupled to inductively coupled plasma mass spectrometry on roots, stems, and leaves extracts describing Hg distribution according to molecular weight and sulfur associations is proposed for the first time. Medium–low molecular weight Hg–S associations of 29–100 kDa were found, suggesting PCs presence. A second approach employing reversed-phase chromatography coupled to atomic fluorescence spectrometry analysis allowed the determination of Hg-PCs complexes within the mentioned fractions. Chromatograms showed Hg-PC2, Hg-PC3 and Hg-PC4 presence only in roots. Hg-PCs presence in roots was confirmed by ESI–MS/MS analysis. 相似文献
998.
Fernanda Ramlov Tiago José Griebeler Carvalho Éder Carlos Schmidt Cintia Dalcuche Leal Martins Marianne Gabi Kreusch Eva Regina de Oliveira Rodrigues Cláudia Marlene Bauer Zenilda Laurita Bouzon Paulo Antunes Horta Marcelo Maraschin 《Journal of applied phycology》2014,26(4):1879-1888
Understanding the mechanisms by which marine organisms cope to environmental stressful conditions is a fundamental question for ecotoxicology. We examined biochemical and cellular responses of Hypnea musciformis exposed in vitro to four concentrations of diesel oil (0 (control), 0.001, 0.01, 0.1, and 1 % v/v) for 0, 30 min, 1, 12, and 24 h. Chl a content decreased after exposure for 1, 12, and 24 h. Carotenoids increased after 30 min and 12 h and decreased after 1 and 24 h. Phenolic content was lower in samples exposed to 0.1 and 1 % of diesel oil. After treatment, samples showed a decrease in floridean starch grains, cell volume and autofluorescence intensity, changes in chloroplast morphology, and on the surface topography of the cell wall. These findings provide preliminary but important results on biochemical and cellular responses of H. musciformis when exposed to diesel oil and could be considered as tools for monitoring oil spills. 相似文献
999.
Maria Florencia Cesani Mariela Garraza María Laura Bergel Sanchís María Antonia Luis María Fernanda Torres Fabián Aníbal Quintero Evelia Edith Oyhenart 《PloS one》2013,8(1)
The purpose of this study was to analyze whether nutritional status and body composition varies according to the environment of residence (urban or rural) of children in the Brandsen district (Argentina). Weight, height, arm circumference and tricipital and subscapular skinfolds were performed in 1368 schoolchildren aged 3 to 14. NHANES III reference was used to estimate nutritional status -underweight, stunting, wasting, overweight, and obesity- and to evaluate body composition -deficit and excess of adipose (DA, EA) and muscular (DM, EM) tissues of the arm-. Central fat distribution (CFD) was estimated using the subscapular-tricipital index. A structured questionnaire was implemented to evaluate socio-environmental characteristics. Nutritional categories based on body size and body composition were compared between urban and rural areas of residence using Chi-squared tests (χ2). The results indicated for the total sample: 1.1% underweight, 6.9% stunting, 0.4% wasting, 12.1% overweight, 9.7% obesity, 22.0% DM, 2.5% EM, 0.1% DA, 17.6% EA, and 8.5% CFD. Significant differences between urban and rural areas were found only for CFD. The socio-environmental analysis showed that while access to public services and housing quality was significantly better in the urban area, a considerable number of city households lived under deficient conditions, lacked health insurance and had low socioeconomic level. Fifty-three percent of the undernourished children had DM without urban-rural significant differences, and none of them showed DA. In the overweight plus obesity group, 62.8% presented EA, 6.4% EM, 4.7% DM, and 22.8% CFD. The highest percentages of DM and CFD were recorded in rural areas (p = 0.00). We conclude that the child population shows the “double burden” of malnutrition. The environment of residence does not promote any differentiation in the nutritional status. Nevertheless, the increment of central adiposity and, in some cases of muscle deficit in rural children, suggests a consumption of unbalanced diet. 相似文献
1000.