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61.
Szalewska-Palasz A Johansson LU Bernardo LM Skärfstad E Stec E Brännström K Shingler V 《The Journal of biological chemistry》2007,282(25):18046-18056
62.
Jorge Nei Silva de Freitas Luciano Augusto da Silva Carvalho Charbel Niño El-Hani Pedro Luís Bernardo da Rocha 《Journal of Ethology》2010,28(1):105-112
In a previous paper, we measured the affiliation between male individuals of Trinomys yonenagae and concluded that the intensity of affiliation was high and did not differ between animals from the same social group and
from different social groups. In this paper, we report the results obtained with the same experimental procedure with female
individuals. We also discuss sexual differences in the social interaction of this species. The experimental procedure was
based on 40-min encounters between residents, which remained alone in an arena for 24 h, and introduced intruders, in a round-robin
design. We quantified one variable indicative of activity level (number of squares crossed), one indicative of anxiety (time
in marginal squares), three indicative of affiliation (number of physical contacts, mean distance between rodents, and total
duration of physical contact), and the number of sound emissions. No aggressive behaviors were exhibited. The results indicate
that there is a high level of affiliation mediated by acoustic communication both for males and females and that no anxiety
is associated with social context, especially in females. The evolution of sociality in T. yonenagae was probably linked to an increase of tolerance especially among adult females. We also suggest that predation was a stronger
selective pressure than resource availability in the evolution of sociality in this species. 相似文献
63.
Activation-induced cytidine deaminase targets DNA at sites of RNA polymerase II stalling by interaction with Spt5 总被引:1,自引:0,他引:1
Pavri R Gazumyan A Jankovic M Di Virgilio M Klein I Ansarah-Sobrinho C Resch W Yamane A Reina San-Martin B Barreto V Nieland TJ Root DE Casellas R Nussenzweig MC 《Cell》2010,143(1):122-133
Activation-induced cytidine deaminase (AID) initiates antibody gene diversification by creating U:G mismatches. However, AID is not specific for antibody genes; Off-target lesions can activate oncogenes or cause chromosome translocations. Despite its importance in these transactions little is known about how AID finds its targets. We performed an shRNA screen to identify factors required for class switch recombination (CSR) of antibody loci. We found that Spt5, a factor associated with stalled RNA polymerase II (Pol II) and single stranded DNA (ssDNA), is required for CSR. Spt5 interacts with AID, it facilitates association between AID and Pol II, and AID recruitment to its Ig and non-Ig targets. ChIP-seq experiments reveal that Spt5 colocalizes with AID and stalled Pol II. Further, Spt5 accumulation at sites of Pol II stalling is predictive of AID-induced mutation. We propose that AID is targeted to sites of Pol II stalling in part via its association with Spt5. 相似文献
64.
A 66-year-old woman developed chronic congestive heart failure after myocardial infarction of the anterior wall of the left ventricle. Angiographic studies revealed total proximal occlusion of the left anterior descending coronary artery and a large saccular aneurysm located on the anteroapical aspect of the left ventricle. Resection of a false aneurysm at operation resulted in improved cardiac function, and the patient made an uneventful recovery. Repeat evaluation six months later confirmed normal cardiac hemodynamics and left ventricular angiographic characteristics. To our knowledge, this is the first documented case of normalized heart function resulting from resection of a false aneurysm of the left ventricle. Functional classification according to the New York Heart Association improved dramatically, rising from Class IV preoperatively to Class I after operation. 相似文献
65.
Rogério da Silva Linhares Denise Petrucci Gigante Fernando Celso Lopes Fernandes de Barros Bernardo Lessa Horta 《PloS one》2015,10(1)
Objective
To examine the relationship between carotid intima-media thickness (IMT) at age 30 and birth characteristics, growth during infancy, and breastfeeding duration, among subjects who have been prospectively followed since birth.Methods and Results
In 1982, all births in the city of Pelotas, southern Brazil, were identified and those children (n = 5,914) whose families lived in the urban area of the city have been followed and evaluated at several time points. The cohort participants were evaluated in 2012–13, and IMT was measured at the posterior wall of the right and left common carotid arteries in longitudinal planes using ultrasound imaging. We obtained valid IMT measurements for 3,188 individuals. Weight-for-age z-score (WAZ) at age 2 years, weight-for-height z-score (WHZ) at age 4, height-for-age z-score (HAZ) at 4 years, WAZ at age 4 and relative conditional weight at 4 years were positively associated with IMT, even after controlling for confounding variables. The beta-coefficient associated with ≥1 s.d. WAZ at age 2 (compared to those with a <–1 s.d.) was 3.62 μm (95% CI 0.86 to 6.38). The beta-coefficient associated with ≥1 s.d. WHZ at 4 (in relation to <–1 s.d) was 3.83 μm (95% CI 0.24 to 7.42). For HAZ at 4, the beta-coefficient for ≥1 s.d. in relation to <–1 s.d. was 4.19 μm (95% CI 1.14 to 7.25). For WAZ at 4, the beta-coefficient associated with ≥1 s.d. in relation to <–1 s.d. was 4.28 μm (95% CI 1.59 to 6.97). The beta-coefficient associated with conditional weight gain at age 2–4 was 1.26 μm (95% CI 0.49 to 2.02).Conclusion
IMT at age 30 was positively associated with WAZ at age 2 years, WHZ at age 4, HAZ at age 4, WAZ at age 4 and conditional weight gain at age 4 years. 相似文献66.
Aírton J. Rombaldi Lúcia C. Pellanda Renata M. Bielemann Denise P. Gigante Pedro C. Hallal Bernardo L. Horta 《PloS one》2015,10(5)
BackgroundThere is conflicting evidence about the association between physical activity and inflammatory markers. Few prospective studies are available, particularly from low and middle-income countries. This study was aimed at assessing the cross-sectional and prospective associations between physical activity and C-reactive protein (CRP) levels in males belonging to the 1982 Pelotas (Brazil) Birth Cohort Study.MethodsThe sample comprised 2,213 males followed up at the ages of 18 and 23 years. We performed high sensitivity CRP assays; we used a cut-off of 3 mg/L in categorical analyses. We measured physical activity by self-report at ages 18 and 23 years. Body mass index and waist circumference were studies as possible mediators.ResultsCRP levels above the 3mg/L cut-off were found in 13.3% (95%CI: 11.7; 14.8) of the individuals. We found no evidence for an association between physical activity (leisure-time or all-domains) and either continuous (geometrical mean) or categorical CRP. We confirmed these null findings in (a) prospective and cross-sectional analyses; (b) trajectories analyses.ConclusionsThere was no association between CRP levels and physical activity levels in early adulthood in a large birth cohort. Little variability in CRP at this early age is the likely explanation for these null findings. 相似文献
67.
M. Fernanda Lima-Costa James Macinko Juliana Vaz de Melo Mambrini Cibele C. Cesar Sérgio V. Peixoto Wagner C. S. Magalh?es Bernardo L. Horta Mauricio Barreto Erico Castro-Costa Josélia O. A. Firmo Fernando A. Proietti Thiago Peixoto Leal Maira R. Rodrigues Alexandre Pereira Eduardo Tarazona-Santos 《PloS one》2015,10(12)
Background
Self-rated health (SRH) has strong predictive value for mortality in different contexts and cultures, but there is inconsistent evidence on ethnoracial disparities in SRH in Latin America, possibly due to the complexity surrounding ethnoracial self-classification.Materials/Methods
We used 370,539 Single Nucleotide Polymorphisms (SNPs) to examine the association between individual genomic proportions of African, European and Native American ancestry, and ethnoracial self-classification, with baseline and 10-year SRH trajectories in 1,311 community dwelling older Brazilians. We also examined whether genomic ancestry and ethnoracial self-classification affect the predictive value of SRH for subsequent mortality.Results
European ancestry predominated among participants, followed by African and Native American (median = 84.0%, 9.6% and 5.3%, respectively); the prevalence of Non-White (Mixed and Black) was 39.8%. Persons at higher levels of African and Native American genomic ancestry, and those self-identified as Non-White, were more likely to report poor health than other groups, even after controlling for socioeconomic conditions and an array of self-reported and objective physical health measures. Increased risks for mortality associated with worse SRH trajectories were strong and remarkably similar (hazard ratio ~3) across all genomic ancestry and ethno-racial groups.Conclusions
Our results demonstrated for the first time that higher levels of African and Native American genomic ancestry—and the inverse for European ancestry—were strongly correlated with worse SRH in a Latin American admixed population. Both genomic ancestry and ethnoracial self-classification did not modify the strong association between baseline SRH or SRH trajectory, and subsequent mortality. 相似文献68.
Background
Hypertrophic scars are one of the most important complications in surgery due to their cosmetic and functional impairments. Previous studies in tissue fibrotic disorders have shown promising results by inhibiting the biological activity effect of Transforming Growth Factor-beta 1 (TGF-β1). The aim of the current study was to determine the clinical effect of the inhibition of TGF-β1 signaling in human hypertrophic scars implanted in nude mice by topical application of an inhibitor of TGF-β1 (P144®).Material and Methods
A total of 30 human hypertrophic scars were implanted in 60 nude mice. The animals were divided in two groups, group A (placebo) and group B (treatment). Group C (basal) was considered as the preimplanted scar samples and they were not implanted in the nude mice. After the shedding period, topical application of a lipogel containing placebo (group A) or P144 (group B) was daily administered during two weeks. The animals were sacrificed upon completion of the study. Total area, thickness and collagen fibers area were measure and compared across all groups. Immunohistochemistry was also performed in order to quantify collagen type I and type III and elastic fiber expressions present in the dermis.Results
Successful shedding was achieved in 83,3% of the xenografts. The mean time for shedding was 35±5.4 days. Statistically significant differences were found in the total area, collagen fibers area and thickness between the groups. Increased elastic fibers and decreased collagen I were found in the P144-treated group compared to the basal group.Conclusion
Topical application of an inhibitor of TGF-β1 may promote scar maturation and clinical improvement of hypertrophic scar morphology features in an “in vivo” model in nude mice after two weeks of treatment. 相似文献69.
Deuan C. Jones Bernardo J. Foth Michael D. Urbaniak Stephen Patterson Han B. Ong Matthew Berriman Alan H. Fairlamb 《PLoS neglected tropical diseases》2015,9(12)
SCYX-7158, an oxaborole, is currently in Phase I clinical trials for the treatment of human African trypanosomiasis. Here we investigate possible modes of action against Trypanosoma brucei using orthogonal chemo-proteomic and genomic approaches. SILAC-based proteomic studies using an oxaborole analogue immobilised onto a resin was used either in competition with a soluble oxaborole or an immobilised inactive control to identify thirteen proteins common to both strategies. Cell-cycle analysis of cells incubated with sub-lethal concentrations of an oxaborole identified a subtle but significant accumulation of G2 and >G2 cells. Given the possibility of compromised DNA fidelity, we investigated long-term exposure of T. brucei to oxaboroles by generating resistant cell lines in vitro. Resistance proved more difficult to generate than for drugs currently used in the field, and in one of our three cell lines was unstable. Whole-genome sequencing of the resistant cell lines revealed single nucleotide polymorphisms in 66 genes and several large-scale genomic aberrations. The absence of a simple consistent mechanism among resistant cell lines and the diverse list of binding partners from the proteomic studies suggest a degree of polypharmacology that should reduce the risk of resistance to this compound class emerging in the field. The combined genetic and chemical biology approaches have provided lists of candidates to be investigated for more detailed information on the mode of action of this promising new drug class. 相似文献
70.
Amanda Priscila de Oliveira Cássia Rubia Bernardo Ana Vitória da Silveira Camargo Luiz Sérgio Ronchi Aldenis Albaneze Borim Cinara Cássia Brand?o de Mattos Eumildo de Campos Júnior Lílian Castiglioni Jo?o Gomes Netinho Carlos Eugênio Cavasini Reinaldo Bulgarelli Bestetti Luiz Carlos de Mattos 《PloS one》2015,10(11)
The clinical manifestations of chronic Chagas disease include the cardiac form of the disease and the digestive form. Not all the factors that act in the variable clinical course of this disease are known. This study investigated whether the CCR5Δ32 (rs333) and CCR5 59029 A/G (promoter region—rs1799987) polymorphisms of the CCR5 gene are associated with different clinical forms of chronic Chagas disease and with the severity of left ventricular systolic dysfunction in patients with chronic Chagas heart disease (CCHD). The antibodies anti-T. cruzi were identified by ELISA. PCR and PCR-RFLP were used to identify the CCR5Δ32 and CCR5 59029 A/G polymorphisms. The chi-square test was used to compare variables between groups. There was a higher frequency of the AA genotype in patients with CCHD compared with patients with the digestive form of the disease and the control group. The results also showed a high frequency of the AG genotype in patients with the digestive form of the disease compared to the other groups. The results of this study show that the CCR5Δ32 polymorphism does not seem to influence the different clinical manifestations of Chagas disease but there is involvement of the CCR5 59029 A/G polymorphism in susceptibility to the different forms of chronic Chagas disease. Besides, these polymorphisms do not influence left ventricular systolic dysfunction in patients with CCHD. 相似文献