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61.
Keller Ricardo Ferreira Sobrinho Ana Carolina Monteiro Santini Carlos Leonardo Sacomani Marques Maicon Gonçalves Gabriel Eduardo de Moura Neto Luciane Aparecida Pascucci Sande de Souza 《Somatosensory & motor research》2013,30(3-4):199-203
AbstractBackground: Unilateral spatial neglect (USN) is the prevalent feature in patients with right-sided stroke. It is diagnosed through the behavior inattention test (BIT) and has a negative impact on patients affecting both their functional capacity and quality of life.Objective: Here, we aimed to evaluate the impact of USN on the quality of life of patients in the chronic phase of stroke.Methods: This is a cross-sectional study with stroke patients with USN. After confirming the presence of stroke through neuroimaging examinations and of USN through the BIT, patients’ quality of life was evaluated by using the EUROQOL scale. Spearman’s correlation was used to validate the correlation between patients’ USN and quality of life, with a p?<?.05 representing significant results.Results: Eighteen individuals were included. When correlating the value of each domain of the EUROQOL scale with the results of the BIT, we observed a negative correlation between mobility (r?=?–0.97; p?=?.000), self-care (r?=?–0.82; p?=?.013), usual activities (r?=?–0.87; p?=?.005); pain or discomfort (r?=?–0.88; p?=?.004), anxiety or depression (r?=?–0.97; p?=?.000), and EUROQOL total score (r?=?–0.97, p?=?.000).Conclusion: After a correlation between the overall EUROQOL and BIT scores, we suggest that the higher the USN degree is in stroke patients, the worse their perceived quality of life tends to be. 相似文献
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64.
Danilo Roman-Campos Policarpo Sales-Júnior Hugo Leonardo Duarte Eneas Ricardo Gomes Silvia Guatimosim Catherine Ropert Ricardo Tostes Gazzinelli Jader Santos Cruz 《Memórias do Instituto Oswaldo Cruz》2013,108(2):243-245
Chagas disease, which is caused by the parasite Trypanosoma cruzi, is an important cause of heart failure. We investigated modifications in the cellular electrophysiological and calcium-handling characteristics of an infected mouse heart during the chronic phase of the disease. The patch-clamp technique was used to record action potentials (APs) and L-type Ca2+ and transient outward K+ currents. [Ca2+]i changes were determined using confocal microscopy. Infected ventricular cells showed prolonged APs, reduced transient outward K+ and L-type Ca2+ currents and reduced Ca2+ release from the sarcoplasmic reticulum. Thus, the chronic phase of Chagas disease is characterised by cardiomyocyte dysfunction, which could lead to heart failure. 相似文献
65.
Sergio A. Coelho-Souza Marcio R. Miranda Leonardo T. Salgado Ricardo Coutinho Jean R. D. Guimaraes 《Microbial ecology》2013,65(2):424-436
The ecological interaction between microorganisms and seaweeds depends on the production of secondary compounds that can influence microbial diversity in the water column and the composition of reef environments. We adapted the 3H-leucine incorporation technique to measure bacterial activity in biofilms associated with the blades of the macroalgae Sargassum spp. We evaluated (1) if the epiphytic bacteria on the blades were more active in detritus or in the biofilm, (2) substrate saturation and linearity of 3H-leucine incorporation, (3) the influence of specific metabolic inhibitors during 3H-leucine incorporation under the presence or absence of natural and artificial light, and (4) the efficiency of radiolabeled protein extraction. Scanning electron microscopy showed heterogeneous distribution of bacteria, diatoms, and polymeric extracellular secretions. Active bacteria were present in both biofilm and detritus on the blades. The highest 3H-leucine incorporation was obtained when incubating blades not colonized by macroepibionts. Incubations done under field conditions reported higher 3H-leucine incorporation than in the laboratory. Light quality and sampling manipulation seemed to be the main factors behind this difference. The use of specific metabolic inhibitors confirmed that bacteria are the main group incorporating 3H-leucine but their association with primary production suggested a symbiotic relationship between bacteria, diatoms, and the seaweed. 相似文献
66.
Sabrina Sacconi Richard J.L.F. Lemmers Judit Balog Patrick J. van der Vliet Pauline Lahaut Merlijn P. van Nieuwenhuizen Kirsten R. Straasheijm Rashmie D. Debipersad Marianne Vos-Versteeg Leonardo Salviati Alberto Casarin Elena Pegoraro Rabi Tawil Egbert Bakker Stephen J. Tapscott Claude Desnuelle Silvère M. van der Maarel 《American journal of human genetics》2013
67.
Sabrina Sacconi Richard?J.L.F. Lemmers Judit Balog Patrick?J. van?der?Vliet Pauline Lahaut Merlijn?P. van?Nieuwenhuizen Kirsten?R. Straasheijm Rashmie?D. Debipersad Marianne Vos-Versteeg Leonardo Salviati Alberto Casarin Elena Pegoraro Rabi Tawil Egbert Bakker Stephen?J. Tapscott Claude Desnuelle Silvère?M. van?der?Maarel 《American journal of human genetics》2013,93(4):744-751
Facioscapulohumeral muscular dystrophy type 1 (FSHD1) is caused by contraction of the D4Z4 repeat array on chromosome 4 to a size of 1–10 units. The residual number of D4Z4 units inversely correlates with clinical severity, but significant clinical variability exists. Each unit contains a copy of the DUX4 retrogene. Repeat contractions are associated with changes in D4Z4 chromatin structure that increase the likelihood of DUX4 expression in skeletal muscle, but only when the repeat resides in a genetic background that contains a DUX4 polyadenylation signal. Mutations in the structural maintenance of chromosomes flexible hinge domain containing 1 (SMCHD1) gene, encoding a chromatin modifier of D4Z4, also result in the increased likelihood of DUX4 expression in individuals with a rare form of FSHD (FSHD2). Because SMCHD1 directly binds to D4Z4 and suppresses somatic expression of DUX4, we hypothesized that SMCHD1 may act as a genetic modifier in FSHD1. We describe three unrelated individuals with FSHD1 presenting an unusual high clinical severity based on their upper-sized FSHD1 repeat array of nine units. Each of these individuals also carries a mutation in the SMCHD1 gene. Familial carriers of the FSHD1 allele without the SMCHD1 mutation were only mildly affected, suggesting a modifier effect of the SMCHD1 mutation. Knocking down SMCHD1 in FSHD1 myotubes increased DUX4 expression, lending molecular support to a modifier role for SMCHD1 in FSHD1. We conclude that FSHD1 and FSHD2 share a common pathophysiological pathway in which the FSHD2 gene can act as modifier for disease severity in families affected by FSHD1. 相似文献
68.
Marzia Boi Juan Antonio Llorens Lucas Cortés Gregorio Lladó Leonardo Llorens 《Grana》2013,52(2):93-105
Measurements and observations of pollen grains of varying structure before and after dehiscence of the anther sac illustrate large magnitudes of harmomegathic changes in volume and shape. Such changes are compared for colpate, porate, and colporate grains, and it is suggested that the nature of the harmomegathal action may serve to distinguish colpi or furrows from pores. Consideration of the requirement to allow harmomegathy while preventing wall collapse may provide at least partial explanation for evolution of the internal structure and external sculpturing of pollen grain walls. 相似文献
69.
Leonardo Leggieri Claudia Feijoó Adonis Giorgi Nicolás Ferreiro Vicenç Acuña 《Hydrobiologia》2013,716(1):47-58
Weather variations change stream hydrological conditions, affecting the stream function. A seasonal study in three well-conserved first-order Pampean streams was carried out to test the hypothesis that rainfalls are the main drivers of whole-stream metabolism, through their effects on hydrology. We estimated the stream metabolism and metabolic contribution of six relevant communities (angiosperms, macroalgae, seston, epiphyton, epipelon, and hyporheos) during late spring, summer, and winter and examined the relation between gross primary production (GPP) and photosynthetic active radiation (PAR). Our results showed that the decrease in available streambed light due to the dissolved organic carbon after rainfalls was the main factor related to the decrease in the ecosystem and community metabolisms. For instance, GPP oscillated from ~10 gO2 m?2 d?1 in early spring (low flows) to ~3 gO2 m?2 d?1 in summer (high flows). Ecosystem respiration (ER) was less sensitive than GPP to rainfalls due to the increase of hyporheic respiration. Rainfalls also caused a significant loss of downstream macroalgal biomass. At a day scale, the high PAR of late spring and summer saturated GPP during the afternoon, and the low temperature of winter mornings constrained GPP. Hence, the knowledge of weather changes is key to understanding the main hydrological drivers of stream function. 相似文献
70.
Daniel R. Lammel Leonardo M. Cruz Helaine Carrer Elke J. B. N. Cardoso 《World journal of microbiology & biotechnology》2013,29(12):2335-2342
While the occurrence of Betaproteobacteria occupying the nodules of tropical legumes has been shown, little is known about subtropical areas. Araucaria Forest is a subtropical endangered ecosystem, and a better understanding of the legume-rhizobial symbionts may allow their use in land reclamation. The 16S rRNA gene of bacteria isolated from nine leguminous species was sequenced and their nodulation tested in Mimosa scabrella and Phaseolus vulgaris. 196 isolates were identified as eight genotypes: Pantoea, Pseudomonas, Bradyrhizobium sp1-2, Rhizobium, and Burkholderia sp1-3. The majority of the isolates from native plants (87 %) were taxonomically related to β-rhizobia, namely Burkholderia, however the legumes Galactia crassifolia and Collea speciosa were nodulated by both α and β-rhizobia, and Acacia dealbata, an exotic plant, only by α-rhizobia. The nifH genes of some isolates were sequenced and N-fixing potential shown by the acetylene reduction test. Most of the isolates nodulated the test plants, some were effective in M. scabrella, but all presented low efficiency in the exotic promiscuous legume P. vulgaris. Pantoea and Pseudomonas did not nodulate and probably are endophytic bacteria. The presented data shows diversity of α, β and γ-Proteobacteria in nodules of subtropical legumes, and suggests host specificity with β-rhizobia. Potential isolates were found for M. scabrella, indicating that a high N-fixing strain may be further inoculated in plants for use in reforestation. 相似文献