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151.
J Atkinson RN Pipitone A Sorokowska P Sorokowski M Mberira A Bartels GG Gallup 《PloS one》2012,7(8):e41811
Evolutionary accounts of human traits are often based on proxies for genetic fitness (e.g., number of sex partners, facial attractiveness). Instead of using proxies, actual differences in reproductive success is a more direct measure of Darwinian fitness. Certain voice acoustics such as fundamental frequency and measures of health such as handgrip strength correlate with proxies of fitness, yet there are few studies showing the relation of these traits to reproduction. Here, we explore whether the fundamental frequency of the voice and handgrip strength account for differences in actual reproduction among a population of natural fertility humans. Our results show that both fundamental frequency and handgrip strength predict several measures of reproductive success among a group of indigenous Namibian females, particularly amongst the elderly, with weight also predicting reproductive outcomes among males. These findings demonstrate that both hormonally regulated and phenotypic quality markers can be used as measures of Darwinian fitness among humans living under conditions that resemble the evolutionary environment of Homo sapiens. We also argue that these findings provide support for the Grandmother Hypothesis. 相似文献
152.
C Baranello M Mariani M Andreoli M Fanelli E Martinelli G Ferrandina G Scambia S Shahabi C Ferlini 《PloS one》2012,7(7):e40678
Stromal elements within a tumor interact with cancer cells to create a microenvironment that supports tumor growth and survival. Adrenomedullin (ADM) is an autocrine/paracrine factor produced by both stromal cells and cancer cells to create such a microenvironment. During differentiation of macrophages, ADM is produced in response to pro-inflammatory stimuli and hypoxia. In this study we investigated the role of ADM as a growth factor for ovarian cancer cells and as a modulator of macrophages. We also analyzed ADM expression levels in a retrospective clinical study using nanofluidic technology and assessment of ADM at the gene level in 220 ovarian cancer patients. To study the effects of ADM, ovarian cancer cell lines A2780, OVCAR-3, and HEY and their drug-resistant counterparts were used for proliferation assays, while monocytes from healthy donors were differentiated in vitro. ADM was a weak growth factor, as revealed by proliferation assays and cell cycle analysis. After culturing cancer cells under stressing conditions, such as serum starvation and/or hypoxia, ADM was found to be a survival factor in HEY but not in other cell lines. In macrophages, ADM showed activity on proliferation/differentiation, primarily in type 2 macrophages (M2). Unexpectedly, the clinical study revealed that high expression of ADM was linked to positive outcome and to cancer with low Ca125. In conclusion, although in vitro ADM was a potential factor in biological aggressiveness, this possibility was not confirmed in patients. Therefore, use of an ADM antagonist would be inappropriate in managing ovarian cancer patients. 相似文献
153.
AC Corte de Araujo H Roschel AR Picanço DM do Prado SM Villares AL de Sá Pinto B Gualano 《PloS one》2012,7(8):e42747
Purpose
To compare two modalities of exercise training (i.e., Endurance Training [ET] and High-Intensity Interval Training [HIT]) on health-related parameters in obese children aged between 8 and 12 years.Methods
Thirty obese children were randomly allocated into either the ET or HIT group. The ET group performed a 30 to 60-minute continuous exercise at 80% of the peak heart rate (HR). The HIT group training performed 3 to 6 sets of 60-s sprint at 100% of the peak velocity interspersed by a 3-min active recovery period at 50% of the exercise velocity. HIT sessions last ∼70% less than ET sessions. At baseline and after 12 weeks of intervention, aerobic fitness, body composition and metabolic parameters were assessed.Results
Both the absolute (ET: 26.0%; HIT: 19.0%) and the relative VO2 peak (ET: 13.1%; HIT: 14.6%) were significantly increased in both groups after the intervention. Additionally, the total time of exercise (ET: 19.5%; HIT: 16.4%) and the peak velocity during the maximal graded cardiorespiratory test (ET: 16.9%; HIT: 13.4%) were significantly improved across interventions. Insulinemia (ET: 29.4%; HIT: 30.5%) and HOMA-index (ET: 42.8%; HIT: 37.0%) were significantly lower for both groups at POST when compared to PRE. Body mass was significantly reduced in the HIT (2.6%), but not in the ET group (1.2%). A significant reduction in BMI was observed for both groups after the intervention (ET: 3.0%; HIT: 5.0%). The responsiveness analysis revealed a very similar pattern of the most responsive variables among groups.Conclusion
HIT and ET were equally effective in improving important health related parameters in obese youth. 相似文献154.
Boyle PM Burrill DR Inniss MC Agapakis CM Deardon A Dewerd JG Gedeon MA Quinn JY Paull ML Raman AM Theilmann MR Wang L Winn JC Medvedik O Schellenberg K Haynes KA Viel A Brenner TJ Church GM Shah JV Silver PA 《Journal of biological engineering》2012,6(1):8
ABSTRACT: BACKGROUND: Plant biotechnology can be leveraged to produce food, fuel, medicine, and materials. Standardized methods advocated by the synthetic biology community can accelerate the plant design cycle, ultimately making plant engineering more widely accessible to bioengineers who can contribute diverse creative input to the design process. RESULTS: This paper presents work done largely by undergraduate students participating in the 2010 International Genetically Engineered Machines (iGEM) competition. Described here is a framework for engineering the model plant Arabidopsis thaliana with standardized, BioBrick compatible vectors and parts available through the Registry of Standard Biological Parts (www.partsregistry.org). This system was used to engineer a proof-of-concept plant that exogenously expresses the taste-inverting protein miraculin. CONCLUSIONS: Our work is intended to encourage future iGEM teams and other synthetic biologists to use plants as a genetic chassis. Our workflow simplifies the use of standardized parts in plant systems, allowing the construction and expression of heterologous genes in plants within the timeframe allotted for typical iGEM projects. 相似文献
155.
Airam Rodríguez Juan J. Negro Mara Mulero Carlos Rodríguez Jesús Hernández-Pliego Javier Bustamante 《PloS one》2012,7(12)
Technological advances for wildlife monitoring have expanded our ability to study behavior and space use of many species. But biotelemetry is limited by size, weight, data memory and battery power of the attached devices, especially in animals with light body masses, such as the majority of bird species. In this study, we describe the combined use of GPS data logger information obtained from free-ranging birds, and environmental information recorded by unmanned aerial systems (UASs). As a case study, we studied habitat selection of a small raptorial bird, the lesser kestrel Falco naumanni, foraging in a highly dynamic landscape. After downloading spatio-temporal information from data loggers attached to the birds, we programmed the UASs to fly and take imagery by means of an onboard digital camera documenting the flight paths of those same birds shortly after their recorded flights. This methodology permitted us to extract environmental information at quasi-real time. We demonstrate that UASs are a useful tool for a wide variety of wildlife studies. 相似文献
156.
Bergemann M Lespinet O M'Barek SB Daboussi MJ Dufresne M 《Journal of molecular evolution》2008,67(6):631-642
We have performed a genome-wide analysis of the mimp family of miniature inverted-repeat transposable elements, taking advantage of the recent release of the F. oxysporum genome sequence. Using different approaches, we detected 103 mimp elements, corresponding to 75 nonredundant copies, half of which are located on a single small chromosome. Phylogenetic analysis
identified at least six subfamilies, all remarkably homogeneous in size and sequence. Based on high sequence identity in the
terminal inverted repeats (TIRs), mimp elements were connected to different impala members. To gain insights into the mechanisms at the origin and amplification of mimps, we studied the potential of impala to cross-mobilize different mimps, native but also created de novo by inserting a short DNA segment between two TIRs. Our results show that TIR sequences are
the main requirement for mobilization but that additional parameters in the internal region are likely to influence transposition
efficiency. Finally, we show that integration site preference of native versus newly transposed mimps greatly varies in the host genomes used in this study.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Nucleotide sequences of novel mimp3 and mimp4 elements are available under GenBank accession numbers EU833100 and EU833101, respectively. Coordinates of mimp5, mimp6 and of non-classified mimp copies are indicated in Supplementary Table 1. 相似文献
157.
Montecalvo A Shufesky WJ Stolz DB Sullivan MG Wang Z Divito SJ Papworth GD Watkins SC Robbins PD Larregina AT Morelli AE 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(5):3081-3090
Exosomes are nanovesicles released by different cell types including dendritic cells (DCs). The fact that exosomes express surface MHC-peptide complexes suggests that they could function as Ag-presenting vesicles or as vehicles to spread allogeneic Ags for priming of anti-donor T cells during elicitation of graft rejection or induction/maintenance of transplant tolerance. We demonstrate that circulating exosomes transporting alloantigens are captured by splenic DCs of different lineages. Internalization of host-derived exosomes transporting allopeptides by splenic DCs leads to activation of anti-donor CD4 T cells by the indirect pathway of allorecognition, a phenomenon that requires DC-derived, instead of exosome-derived, MHC class II molecules. By contrast, allogeneic exosomes are unable to stimulate direct-pathway T cells in vivo. We demonstrate in mice that although graft-infiltrating leukocytes release exosomes ex vivo, they do not secrete enough concentrations of exosomes into circulation to stimulate donor-reactive T cells in secondary lymphoid organs. Instead, our findings indicate that migrating DCs (generated in vitro or isolated from allografts), once they home in the spleen, they transfer exosomes expressing the reporter marker GFP to spleen-resident DCs. Our results suggest that exchange of exosomes between DCs in lymphoid organs might constitute a potential mechanism by which passenger leukocytes transfer alloantigens to recipient's APCs and amplify generation of donor-reactive T cells following transplantation. 相似文献
158.
L. Gómez‐Aparicio I. M. Pérez‐Ramos I. Mendoza L. Matías J. L. Quero J. Castro R. Zamora T. Marañón 《Oikos》2008,117(11):1683-1699
Understanding seedling performance across resource gradients is crucial for defining the regeneration niche of plant species under current environmental conditions and for predicting potential changes under a global change scenario. A 2‐year field experiment was conducted to determine how seedling survival and growth of two evergreen and two deciduous Quercus species vary along gradients of light and soil properties in two Mediterranean forests with contrasting soils and climatic conditions. Half the seedlings were subjected to an irrigation treatment during the first year to quantify the effects on performance of an alteration in the summer drought intensity. Linear and non‐linear models were parameterized and compared to identify major resources controlling seedling performance. We found both site‐specific and general patterns of regeneration. Strong site‐specificity was found in the identity of the best predictors of seedling survival: survival decreased linearly with increasing light (i.e. increasing desiccation risk) in the drier site, whereas it decreased logistically with increasing spring soil water content (i.e. increasing waterlogging risk) in the wetter site. We found strong empirical support for multiple resource limitation at the drier site, the response to light being modulated by the availability of soil resources (water and P). Evidence for regeneration niche partitioning among Quercus species was only found at the wetter site. However, at both sites Quercus species shared the same response to summer drought alleviation through water addition: increased first‐year survival but not final survival (i.e. after two years). This suggests that extremely dry summers (i.e. the second summer in the experiment) can cancel out the positive effects of previous wetter summers. Therefore, an increase in the intensity and frequency of summer drought with climate change might cause a double negative impact on Quercus regeneration, due to a general reduction in survival probability and the annulment of the positive effects of (infrequent) ‘wet’ years. Overall, results presented in this study are a major step towards the development of a mechanistic model of Mediterranean forest dynamics that incorporates the idiosyncrasies and generalities of tree regeneration in these systems, and that allow simulation and prediction of the ecological consequences of resource level alterations due to global change. 相似文献
159.
Busso N Karababa M Nobile M Rolaz A Van Gool F Galli M Leo O So A De Smedt T 《PloS one》2008,3(5):e2267
Nicotinamide phosphoribosyltransferase (NAMPT), also known as visfatin, is the rate-limiting enzyme in the salvage pathway of NAD biosynthesis from nicotinamide. Since its expression is upregulated during inflammation, NAMPT represents a novel clinical biomarker in acute lung injury, rheumatoid arthritis, and Crohn's disease. However, its role in disease progression remains unknown. We report here that NAMPT is a key player in inflammatory arthritis. Increased expression of NAMPT was confirmed in mice with collagen-induced arthritis, both in serum and in the arthritic paw. Importantly, a specific competitive inhibitor of NAMPT effectively reduced arthritis severity with comparable activity to etanercept, and decreased pro-inflammatory cytokine secretion in affected joints. Moreover, NAMPT inhibition reduced intracellular NAD concentration in inflammatory cells and circulating TNFalpha levels during endotoxemia in mice. In vitro pharmacological inhibition of NAMPT reduced the intracellular concentration of NAD and pro-inflammatory cytokine secretion by inflammatory cells. Thus, NAMPT links NAD metabolism to inflammatory cytokine secretion by leukocytes, and its inhibition might therefore have therapeutic efficacy in immune-mediated inflammatory disorders. 相似文献
160.
Reports of centromere pairing in early meiotic cells have appeared sporadically over the past thirty years. Recent experiments demonstrate that early centromere pairing occurs between non-homologous centromeres. As meiosis proceeds, centromeres change partners, becoming arranged in homologous pairs. Investigations of these later centromere pairs indicate that paired homologous centromeres are actively associated rather than positioned passively, side-by-side. Meiotic centromere pairing has been observed in organisms as diverse as mice, wheat and yeast, indicating that non-homologous centromere pairing in early meiosis and active homologous centromere pairing in later meiosis might be themes in meiotic chromosome behavior. Moreover, such pairing could have previously unrecognized roles in mediating chromosome organization or architecture that impact meiotic segregation fidelity. 相似文献