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21.
László Kékesi Anna Sipos Gábor Németh János Pató Nóra Breza Ferenc Baska László Őrfi György Kéri 《Bioorganic & medicinal chemistry letters》2013,23(22):6152-6155
A series of novel pyrido[2,3-b]pyrazines were synthesized as potential antitumor agents for erlotinib-resistant tumors. Known signal inhibitor compounds from our Nested Chemical Library were tested in phenotypic assays on erlotinib-sensitive PC9 and erlotinib-resistant PC9-ER cell lines to find a compound class to be active on erlotinib resistant cell lines. Based on the screening data, novel pyrido[2,3-b]pyrazines were designed and synthesized. The effect of the substituent position of the heteroaromatic moiety in position 7 and the importance of unsubstituted position 2 of the pyridopyrazine core were explored. Compound 7n had an IC50 value of 0.09 μM for the inhibition of PC9 and 0.15 μM for the inhibition of PC9-ER. We found that some lead compounds of these structures overcome erlotinib-resistance which might become promising drug candidates to fight against NSCLC with EGFR T790M mutation. The signaling network(s) involved in the mechanism(s) of action of these novel compounds in overcoming erlotinib resistance remain to be elucidated. 相似文献
22.
François Bilodeau Murray D. Bailey Punit K. Bhardwaj Josée Bordeleau Pat Forgione Michel Garneau Elise Ghiro Vida Gorys Ted Halmos Eric S. Jolicoeur Mélissa Leblanc Christopher T. Lemke Julie Naud Jeff O’Meara Peter W. White Montse Llinàs-Brunet 《Bioorganic & medicinal chemistry letters》2013,23(14):4267-4271
In this report we describe the synthesis and evaluation of diverse 4-arylproline analogs as HCV NS3 protease inhibitors. Introduction of this novel P2 moiety opened up new SAR and, in combination with a synthetic approach providing a versatile handle, allowed for efficient exploitation of this novel series of NS3 protease inhibitors. Multiple structural modifications of the aryl group at the 4-proline, guided by structural analysis, led to the identification of analogs which were very potent in both enzymatic and cell based assays. The impact of this systematic SAR on different drug properties is reported. 相似文献
23.
Phillip Gorrindo Christianne Joy Lane Evon Batey Lee BethAnn McLaughlin Pat Levitt 《PloS one》2013,8(7)
Etiology is unknown in the majority of individuals with autism spectrum disorder (ASD). One strategy to investigate pathogenesis is to stratify this heterogeneous disorder based on a prominent phenotypic feature that enriches for homogeneity within population strata. Co-occurring gastrointestinal dysfunction (GID) characterizes a subset of children with ASD. Our current objective was to investigate a potential pathophysiological measure to test the hypothesis that children with both ASD and GID have a more severe metabolic dysfunction than children with ASD-only, given that the highly metabolically active brain and gastrointestinal system may additively contribute measurable impairment. Plasma levels of F2t-Isoprostanes (F2-IsoPs), a gold standard biomarker of oxidative stress, were measured in 87 children in four groups: ASD-GID, ASD-only, GID-only and Unaffected. F2-IsoP levels were elevated in all 3 clinical groups compared to the Unaffected group, with the ASD-GID group significantly elevated above the ASD-only group (mean, SD in pg/mg: ASD-GID 53.6, 24.4; ASD-only 36.5, 13.3; p = 0.007). Adjusting for age, sex, and triglyceride levels, F2-IsoP levels remained significantly different between study groups, with a moderate effect size of ηp
2 = 0.187 (p = 0.001). Elevation in peripheral oxidative stress is consistent with, and may contribute to, the more severe functional impairments in the ASD-GID group. With unique medical, metabolic, and behavioral features in children with ASD-GID, the present findings serve as a compelling rationale for both individualized approaches to clinical care and integrated studies of biomarker enrichment in ASD subgroups that may better address the complex etiology of ASD. 相似文献
24.
IntroductionThe epidemiology of chronic myeloid leukemia (CML) in low and middle income countries is limited. As a result, we analyzed a contemporary cohort of patients from low and middle income countries treated with Imatinib through The Glivec® International Patient Assistance Program (GIPAP).MethodsGeneralized estimating equations (GEE) and Kaplan–Meier estimation were utilized to test for regional variations in age at diagnosis and overall survival among 33,985 patients from 94 countries.ResultsPatients participated from Asia (79.2%), Africa (9.4%), Latin America (8.7%) and Southern/Eastern Europe (2.5%). Sixty-one (61.2%) percent were male. Mean age at diagnosis was 38.5 years (9.4% <20 years and only 4.7% ≥65 years). Using GEE, Asians were youngest (38.3 years), followed by Africans (39.5 years), Southern/Eastern Europeans (41.1 years) and Latin Americans (41.3 years; p < 0.0001). Diagnoses were predominately in chronic stage (78.3%). In 2002, 85.2% of patients had a delay in treatment >1 year; decreasing to 15.5% in 2010 (p < 0.0001). The 3-year overall survival probability was 89.4% (95% CI, 88.9–89.9). In multivariate analysis, risk of death increased among patients 65 years or older at diagnosis (p < 0.0001), time from diagnosis to treatment >1-year (p < 0.0001), diagnoses in the accelerated or blast crisis (p < 0.0001), initial dose of Imatinib >400 mg (p < 0.0001) and among Latin Americans and Africans (p < 0.0001).ConclusionThe GIPAP cohort is the largest series of patients with CML described from low and middle income countries. Differences in age at diagnosis and overall survival exist within and between regions. Additional epidemiological studies should be conducted to assess for possible environmental factors associated with the earlier age at onset. 相似文献
25.
Objectives
To quantify the proportion of adverse pregnancy outcome attributable to maternal obesity.Design
Cross sectional analysis of routine obstetric dataset.Setting
Guy’s and St Thomas’s NHS Foundation Trust (GSTFT).Population
23,668 women who had singleton deliveries at GSTFT between 2004 and 2008.Methods
Logistic regression was used to estimate the association between BMI and outcome in different ethnic groups. Adjusted odds ratios, and the proportions of obese women, were used to calculate population attributable risk fractions (PAFs).Main Outcome Measures
(i) Maternal outcomes: diabetes, type of delivery, post-partum haemorrhage, and preterm delivery. (ii) Perinatal outcomes: macrosomia, low birth weight, admission to neonatal intensive care/special care baby unit, and perinatal death.Results
The prevalence of maternal obesity was 14%. Increasing BMI was independently associated with increasing risk of adverse obstetric and neonatal outcome. At the individual level, the effect of obesity on diabetes was highest in Asian women compared to white women (p for interaction = 0.03). Calculation of population attributable risk fractions demonstrated that one third of diabetes cases and one in six Caesarean sections could be avoided in this population if all obese women were of normal BMI. At the population level, the contribution of obesity to diabetes was highest for Black women (42%), and lowest for oriental women (8%). Seven percent of neonatal macrosomia in all the population, and 13% in Black mothers, were attributable to obesity.Conclusions
Preventing obesity prior to pregnancy will substantially reduce the burden of obstetric and neonatal morbidity in this population. This reduction will be higher in Black women. 相似文献26.
Distinct intracellular signaling mediates C‐MET regulation of dendritic growth and synaptogenesis 下载免费PDF全文
Kathie L. Eagleson Christianne J. Lane Lisa McFadyen‐Ketchum Sara Solak Hsiao‐Huei Wu Pat Levitt 《Developmental neurobiology》2016,76(10):1160-1181
Hepatocyte growth factor (HGF) activation of the MET receptor tyrosine kinase influences multiple neurodevelopmental processes. Evidence from human imaging and mouse models shows that, in the forebrain, disruptions in MET signaling alter circuit formation and function. One likely means of modulation is by controlling neuron maturation. Here, we examined the signaling mechanisms through which MET exerts developmental effects in the neocortex. In situ hybridization revealed that hgf is located near MET‐expressing neurons, including deep neocortical layers and periventricular zones. Western blot analyses of neocortical crude membranes demonstrated that HGF‐induced MET autophosphorylation peaks during synaptogenesis, with a striking reduction in activation between P14 and P17 just before pruning. In vitro analysis of postnatal neocortical neurons assessed the roles of intracellular signaling following MET activation. There is rapid, HGF‐induced phosphorylation of MET, ERK1/2, and Akt that is accompanied by two major morphological changes: increases in total dendritic growth and synapse density. Selective inhibition of each signaling pathway altered only one of the two distinct events. MAPK/ERK pathway inhibition significantly reduced the HGF‐induced increase in dendritic length, but had no effect on synapse density. In contrast, inhibition of the PI3K/Akt pathway reduced HGF‐induced increases in synapse density, with no effect on dendritic length. The data reveal a key role for MET activation during the period of neocortical neuron growth and synaptogenesis, with distinct biological outcomes mediated via discrete MET‐linked intracellular signaling pathways in the same neurons. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1160–1181, 2016 相似文献
27.
Computational ecology is an emerging interdisciplinary discipline founded mainly on modeling and simulation methods for studying ecological systems. Among the existing modeling formalisms, the individual‐based modeling is particularly well suited for capturing the complex temporal and spatial dynamics as well as the nonlinearities arising in ecosystems, communities, or populations due to individual variability. In addition, being a bottom‐up approach, it is useful for providing new insights on the local mechanisms which are generating some observed global dynamics. Of course, no conclusions about model results could be taken seriously if they are based on a single model execution and they are not analyzed carefully. Therefore, a sound methodology should always be used for underpinning the interpretation of model results. The sensitivity analysis is a methodology for quantitatively assessing the effect of input uncertainty in the simulation output which should be incorporated compulsorily to every work based on in‐silico experimental setup. In this article, we present R/Repast a GNU R package for running and analyzing Repast Simphony models accompanied by two worked examples on how to perform global sensitivity analysis and how to interpret the results. 相似文献
28.
29.
Leonardo da Costa Bastos Felipe Rodrigues de Souza Ana Paula Guimarães Mehdi Sirouspour Teobaldo Ricardo Cuya Guizado Pat Forgione 《Journal of biomolecular structure & dynamics》2016,34(10):2184-2198
In the present work, we propose to design drugs that target the enzyme dihydrofolate redutase (DHFR) as a means of a novel drug therapy against plague. Potential inhibitors of DHFR from Yersinia pestis (YpDHFR) were selected by virtual screening and subjected to docking, molecular dynamics (MD) simulations, and Poisson–Boltzmann surface area method, in order to evaluate their interactions in the active sites of YpDHFR and human DHFR (HssDHFR). The results suggested selectivity for three compounds that were further used to propose the structures of six new potential selective inhibitors for YpDHFR. 相似文献
30.