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161.
Cailu Lin Brad D. Fesi Michael Marquis Natalia P. Bosak Maria L. Theodorides Mauricio Avigdor Amanda H. McDaniel Fujiko F. Duke Anna Lysenko Amin Khoshnevisan Brian R. Gantick Charles J. Arayata Theodore M. Nelson Alexander A. Bachmanov Danielle R. Reed 《PloS one》2015,10(11)
Genetic variation contributes to individual differences in obesity, but defining the exact relationships between naturally occurring genotypes and their effects on fatness remains elusive. As a step toward positional cloning of previously identified body composition quantitative trait loci (QTLs) from F2 crosses of mice from the C57BL/6ByJ and 129P3/J inbred strains, we sought to recapture them on a homogenous genetic background of consomic (chromosome substitution) strains. Male and female mice from reciprocal consomic strains originating from the C57BL/6ByJ and 129P3/J strains were bred and measured for body weight, length, and adiposity. Chromosomes 2, 7, and 9 were selected for substitution because previous F2 intercross studies revealed body composition QTLs on these chromosomes. We considered a QTL confirmed if one or both sexes of one or both reciprocal consomic strains differed significantly from the host strain in the expected direction after correction for multiple testing. Using these criteria, we confirmed two of two QTLs for body weight (Bwq5-6), three of three QTLs for body length (Bdln3-5), and three of three QTLs for adiposity (Adip20, Adip26 and Adip27). Overall, this study shows that despite the biological complexity of body size and composition, most QTLs for these traits are preserved when transferred to consomic strains; in addition, studying reciprocal consomic strains of both sexes is useful in assessing the robustness of a particular QTL. 相似文献
162.
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163.
Guaraci Ken Tanaka Tolou Maslahati Mariana Gongora Juliana Bittencourt Luiz Carlos Serramo Lopez Marcelo Marcos Piva Demarzo Henning Budde Silmar Teixeira Luis Fernando Basile Javier Garcia Campayo Mauricio Cagy Pedro Ribeiro Bruna Velasques 《PloS one》2015,10(10)
Objective
The present study aimed at comparing frontal beta power between long-term (LTM) and first-time meditators (FTM), before, during and after a meditation session. We hypothesized that LTM would present lower beta power than FTM due to lower effort of attention and awareness.Methods
Twenty one participants were recruited, eleven of whom were long-term meditators. The subjects were asked to rest for 4 minutes before and after open monitoring (OM) meditation (40 minutes).Results
The two-way ANOVA revealed an interaction between the group and moment factors for the Fp1 (p<0.01), F7 (p = 0.01), F3 (p<0.01), Fz (p<0.01), F4 (p<0.01), F8 (p<0.01) electrodes.Conclusion
We found low power frontal beta activity for LTM during the task and this may be associated with the fact that OM is related to bottom-up pathways that are not present in FTM.Significance
We hypothesized that the frontal beta power pattern may be a biomarker for LTM. It may also be related to improving an attentive state and to the efficiency of cognitive functions, as well as to the long-term experience with meditation (i.e., life-time experience and frequency of practice). 相似文献164.
We developed a model to demonstrate how a hopping kangaroo breathes. Interestingly, a kangaroo uses less energy to breathe while hopping than while standing still. This occurs, in part, because rather than using muscle power to move air into and out of the lungs, air is pulled into (inspiration) and pushed out of (expiration) the lungs as the abdominal organs "flop" within the kangaroo's body. Specifically, as the kangaroo hops upward, the abdominal organs lag behind, and the insertion of the diaphragm is pulled toward its origin, flattening the dome and increasing the vertical dimension of the thoracic cavity (the thoracic cavity and lungs enlarge). Increasing the volume of the thoracic cavity reduces alveolar pressure below atmospheric pressure (barometric pressure), and air moves into the alveoli by bulk flow. In contrast, the impact of the organs against the diaphragm at each landing causes expiration. Specifically, upon landing, the abdominal organs flop into the diaphragm, causing it to return to its dome shape and decreasing the vertical dimension of the thoracic cavity. This compresses the alveolar gas volume and elevates alveolar pressure above barometric pressure, so air is expelled. To demonstrate this phenomenon, the plunger of a syringe model of the respiratory system was inserted through a compression spring. Holding the syringe and pressing the plunger firmly against a hard surface expels air from the lungs (the balloon within the syringe deflates) and compresses the spring. This models the kangaroo landing after a hop forward. Subsequently, the compression spring provides the energy for the "kangaroo" to "hop" forward upon the release of the syringe, and air enters the lungs (the balloon within the syringe inflates). The model accurately reflects how a hopping kangaroo breathes. A model was chosen to demonstrate this phenomenon because models engage and inspire students as well as significantly enhance student understanding. 相似文献
165.
Hortensia Rodríguez Margarita Suarez Fernando Albericio 《Journal of peptide science》2010,16(3):136-140
Structural modification of the peptide backbone via N‐methylation is a powerful tool to modulate the pharmacokinetic profile and biological activity of peptides. Here we describe a rapid and highly efficient microwave(MW)‐assisted Fmoc/tBu solid‐phase method to prepare short chain N‐methyl‐rich peptides, using Rink amide p‐methylbenzhydrylamine (MBHA) resin as solid‐phase support. This method produces peptides in high yield and purity, and reduces the time required for Fmoc‐N‐methyl amino acid coupling. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
166.
Kim H Jürgens P Weber S Nolte LP Reyes M 《Progress in biophysics and molecular biology》2010,103(2-3):284-291
We propose a computationally efficient, bio-mechanically relevant soft-tissue simulation method for cranio-maxillofacial (CMF) surgery. Special emphasis is given to comply with the current clinical workflow. A template-based facial muscle prediction was introduced to avoid laborious segmentation from medical images. In addition, transversely isotropic mass-tensor model (MTM) was applied to realize the directional behavior of facial muscles in short computation time. Finally, sliding contact was incorporated to mimic realistic boundary condition in error-sensitive regions. Mechanical simulation result was compared with commercial finite element software. And retrospective validation study with post-operative scan of four CMF cases was performed. 相似文献
167.
Mauricio Hunsche Kathrin Bürling Amina Sirag Saied Michaela Schmitz-Eiberger Muhammad Sohail Jens Gebauer Georg Noga Andreas Buerkert 《Plant Growth Regulation》2010,61(3):253-263
Seedlings of the salt-tolerant plant grewia [Grewia tenax (Forssk.) Fiori] and the moderately salt-tolerant tamarind (Tamarindus indica L.) were grown under controlled conditions and treated daily with NaCl solutions to investigate mechanisms of tolerance to
salinity. Leaf micromorphology, cuticular wax load, chlorophyll fluorescence and light remission, as well as antioxidative
potential were evaluated. As confirmed by energy-dispersive X-ray microanalysis in both species, absorption of sodium and
chlorine increased with rising NaCl concentration in the treatment solution. In parallel, accumulation of calcium in grewia
leaves was strongly reduced, leading to less crystals of calcium oxalate in leaf tissue. In grewia the cuticular wax load,
chlorophyll content, and electron transport rate (ETR) were significantly reduced by comparatively low NaCl concentrations.
In tamarind, in contrast, wax load and ETR were not significantly affected, while the decrease of chlorophyll content was
less pronounced. Measurements of the antioxidative capacity and the imbalance between values of lipophilic and hydrophilic
extracts at different NaCl concentrations confirmed that grewia is more salt tolerant than tamarind. This higher tolerance
degree seemed to be associated with grewias’ more efficient scavenging of free radicals and the regulation of the antioxidative
potential in lipophilic and hydrophilic extracts. 相似文献
168.
169.
Mauricio Soto-Suárez Diana Bernal Carolina González Boris Szurek Romain Guyot Joe Tohme Valérie Verdier 《BMC microbiology》2010,10(1):170
Background
Bacterial leaf blight causes significant yield losses in rice crops throughout Asia and Africa. Although both the Asian and African strains of the pathogen, Xanthomonas oryzae pv. oryzae (Xoo), induce similar symptoms, they are nevertheless genetically different, with the African strains being more closely related to the Asian X. oryzae pv. oryzicola (Xoc). 相似文献170.
Several specimens of Mytilus galloprovincialis, collected in the Ria of Vigo over a non-consecutive 2 yr period (1993 to 1994 and 1996 to 1997), presented a possible gonadal neoplasm, entailing morphologically abnormal germinal cells distributed throughout the follicle and invading the adjacent storage tissue. In some cases, affected cells were noted in gonoducts and in haemic sinusoids. Prevalence of this anomaly in the samples was 6%, and all affected individuals were found between April and June. During the rest of the year, individuals presented normal gonadal tissue. 相似文献