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991.
Gerard J. P. van Westen Andreas Bender John P. Overington 《Journal of chemical biology》2014,7(4):119-123
Resistance to pesticides is an increasing problem in agriculture. Despite practices such as phased use and cycling of ‘orthogonally resistant’ agents, resistance remains a major risk to national and global food security. To combat this problem, there is a need for both new approaches for pesticide design, as well as for novel chemical entities themselves. As summarized in this opinion article, a technique termed ‘proteochemometric modelling’ (PCM), from the field of chemoinformatics, could aid in the quantification and prediction of resistance that acts via point mutations in the target proteins of an agent. The technique combines information from both the chemical and biological domain to generate bioactivity models across large numbers of ligands as well as protein targets. PCM has previously been validated in prospective, experimental work in the medicinal chemistry area, and it draws on the growing amount of bioactivity information available in the public domain. Here, two potential applications of proteochemometric modelling to agrochemical data are described, based on previously published examples from the medicinal chemistry literature. 相似文献
992.
993.
Shaul Raviv Kapil Bharti Sigal Rencus-Lazar Yamit Cohen-Tayar Rachel Schyr Naveh Evantal Eran Meshorer Alona Zilberberg Maria Idelson Benjamin Reubinoff Rhonda Grebe Rina Rosin-Arbesfeld James Lauderdale Gerard Lutty Heinz Arnheiter Ruth Ashery-Padan 《PLoS genetics》2014,10(5)
During organogenesis, PAX6 is required for establishment of various progenitor subtypes within the central nervous system, eye and pancreas. PAX6 expression is maintained in a variety of cell types within each organ, although its role in each lineage and how it acquires cell-specific activity remain elusive. Herein, we aimed to determine the roles and the hierarchical organization of the PAX6-dependent gene regulatory network during the differentiation of the retinal pigmented epithelium (RPE). Somatic mutagenesis of Pax6 in the differentiating RPE revealed that PAX6 functions in a feed-forward regulatory loop with MITF during onset of melanogenesis. PAX6 both controls the expression of an RPE isoform of Mitf and synergizes with MITF to activate expression of genes involved in pigment biogenesis. This study exemplifies how one kernel gene pivotal in organ formation accomplishes a lineage-specific role during terminal differentiation of a single lineage. 相似文献
994.
Tomislav Hengl Jorge Mendes de Jesus Robert A. MacMillan Niels H. Batjes Gerard B. M. Heuvelink Eloi Ribeiro Alessandro Samuel-Rosa Bas Kempen Johan G. B. Leenaars Markus G. Walsh Maria Ruiperez Gonzalez 《PloS one》2014,9(8)
BackgroundSoils are widely recognized as a non-renewable natural resource and as biophysical carbon sinks. As such, there is a growing requirement for global soil information. Although several global soil information systems already exist, these tend to suffer from inconsistencies and limited spatial detail.Conclusions/SignificanceSoilGrids1km provide an initial set of examples of soil spatial data for input into global models at a resolution and consistency not previously available. Some of the main limitations of the current version of SoilGrids1km are: (1) weak relationships between soil properties/classes and explanatory variables due to scale mismatches, (2) difficulty to obtain covariates that capture soil forming factors, (3) low sampling density and spatial clustering of soil profile locations. However, as the SoilGrids system is highly automated and flexible, increasingly accurate predictions can be generated as new input data become available. SoilGrids1km are available for download via http://soilgrids.org under a Creative Commons Non Commercial license. 相似文献
995.
996.
Sarah Hanieh Tran T. Ha Julie A. Simpson Gerard J. Casey Nguyen C. Khuong Dang D. Thoang Tran T. Thuy Sant-Rayn Pasricha Thach D. Tran Tran Tuan Terence Dwyer Jane Fisher Beverley-Ann Biggs 《PLoS medicine》2013,10(6)
Background
Anemia affects over 500 million women, and in pregnancy is associated with impaired maternal and infant outcomes. Intermittent antenatal iron supplementation is an attractive alternative to daily dosing; however, the impact of this strategy on infant outcomes remains unclear. We compared the effect of intermittent antenatal iron supplementation with daily iron supplementation on maternal and infant outcomes in rural Viet Nam.Methods and Findings
This cluster randomised trial was conducted in Ha Nam province, Viet Nam. 1,258 pregnant women (<16 wk gestation) in 104 communes were assigned to daily iron–folic acid (IFA), twice weekly IFA, or twice weekly multiple micronutrient (MMN) supplementation. Primary outcome was birth weight. Mean birth weight was 3,148 g (standard deviation 416). There was no difference in the birth weights of infants of women receiving twice weekly IFA compared to daily IFA (mean difference [MD] 28 g; 95% CI −22 to 78), or twice weekly MMN compared to daily IFA (MD −36.8 g; 95% CI −82 to 8.2). At 32 wk gestation, maternal ferritin was lower in women receiving twice weekly IFA compared to daily IFA (geometric mean ratio 0.73; 95% CI 0.67 to 0.80), and in women receiving twice weekly MMN compared to daily IFA (geometric mean ratio 0.62; 95% CI 0.57 to 0.68), but there was no difference in hemoglobin levels. Infants of mothers who received twice weekly IFA had higher cognitive scores at 6 mo of age compared to those who received daily IFA (MD 1.89; 95% CI 0.23 to 3.56).Conclusions
Twice weekly antenatal IFA or MMN did not produce a clinically important difference in birth weight, when compared to daily IFA supplementation. The significant improvement in infant cognitive outcomes at 6 mo of age following twice weekly antenatal IFA requires further exploration, and provides additional support for the use of intermittent, rather than daily, antenatal IFA in populations with low rates of iron deficiency.Trial registration
Australia New Zealand Clinical Trials Registry 12610000944033 Please see later in the article for the Editors'' Summary 相似文献997.
Jane Owens Karen Moreira Gerard Bain 《In vitro cellular & developmental biology. Animal》2013,49(9):695-705
There is a significant unmet need for safe, anabolic muscle therapies to treat diseases and conditions associated with severe muscle weakness and frailty. The identification of such therapies requires appropriate cell-based screening assays to select compounds for further development using animal models. Primary human skeletal muscle cells have recently become available from a number of commercial vendors. Such cells may be valuable for studying the mechanisms that direct muscle differentiation, and for identifying and characterizing novel therapeutic approaches for the treatment of age- and injury-induced muscle disorders. However, only limited characterization of these cells has been reported to date. Therefore, we have examined four primary human muscle cell preparations from three different vendors for their capacity to differentiate into multinucleated myotubes. Two of the preparations demonstrated robust myotube formation and expressed characteristic markers of muscle differentiation. Furthermore, these myotubes could be induced to undergo morphological atrophy- and hypertrophy-like responses, and atrophy could be blocked with an inhibitor of myostatin signaling, a pathway that is known to negatively regulate muscle mass. Finally, the myotubes were efficiently infected with recombinant adenovirus, providing a tool for genetic modification. Taken together, our results indicate that primary human muscle cells can be a useful system for studying muscle differentiation, and may also provide tools for studying new therapeutic molecules for the treatment of muscle disease. 相似文献
998.
Michiko Mori Cecilia K Andersson Gerard J Graham Claes-G?ran L?fdahl Jonas S Erjef?lt 《Respiratory research》2013,14(1):65
Background
De novo lymphatic vessel formation has recently been observed in lungs of patients with moderate chronic obstructive pulmonary disease (COPD). However, the distribution of lymphatic vessel changes among the anatomical compartments of diseased lungs is unknown. Furthermore, information regarding the nature of lymphatic vessel alterations across different stages of COPD is missing. This study performs a detailed morphometric characterization of lymphatic vessels in major peripheral lung compartments of patients with different severities of COPD and investigates the lymphatic expression of molecules involved in immune cell trafficking.Methods
Peripheral lung resection samples obtained from patients with mild (GOLD stage I), moderate-severe (GOLD stage II-III), and very severe (GOLD stage IV) COPD were investigated for podoplanin-immunopositive lymphatic vessels in distinct peripheral lung compartments: bronchioles, pulmonary blood vessels and alveolar walls. Control subjects with normal lung function were divided into never smokers and smokers. Lymphatics were analysed by multiple morphological parameters, as well as for their expression of CCL21 and the chemokine scavenger receptor D6.Results
The number of lymphatics increased by 133% in the alveolar parenchyma in patients with advanced COPD compared with never-smoking controls (p < 0.05). In patchy fibrotic lesions the number of alveolar lymphatics increased 20-fold from non-fibrotic parenchyma in the same COPD patients. The absolute number of lymphatics per bronchiole and artery was increased in advanced COPD, but numbers were not different after normalization to tissue area. Increased numbers of CCL21- and D6-positive lymphatics were observed in the alveolar parenchyma in advanced COPD compared with controls (p < 0.01). Lymphatic vessels also displayed increased mean levels of immunoreactivity for CCL21 in the wall of bronchioles (p < 0.01) and bronchiole-associated arteries (p < 0.05), as well as the alveolar parenchyma (p < 0.001) in patients with advanced COPD compared with never-smoking controls. A similar increase in lymphatic D6 immunoreactivity was observed in bronchioles (p < 0.05) and alveolar parenchyma (p < 0.01).Conclusions
This study shows that severe stages of COPD is associated with increased numbers of alveolar lymphatic vessels and a change in lymphatic vessel phenotype in major peripheral lung compartments. This novel histopathological feature is suggested to have important implications for distal lung immune cell traffic in advanced COPD. 相似文献999.
Gerard Delanty 《New genetics and society》2013,32(3):279-289
In this paper it is argued that the social sciences, especially sociology, cannot afford to ignore the challenge that is coming from the new genetics. This will involve rethinking some of the epistemological assumptions of modernist social science, which has always assumed the separation of nature and society. The argument made in this article is that a qualified version of constructivism points to a possible opening within the sciences for a reorientation for sociology and in a way that the new genetics can be addressed in a serious way. 相似文献
1000.