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排序方式: 共有2827条查询结果,搜索用时 15 毫秒
81.
Ryan C. Lewis John D. Meeker Niladri Basu Alison M. Gauthier Alejandra Cantoral Adriana Mercado-García Karen E. Peterson Martha Maria Téllez-Rojo Deborah J. Watkins 《International journal of hygiene and environmental health》2018,221(4):609-615
Personal care product use is a potential source of metals exposure among children, but studies have been limited. We measured urinary concentrations of 10 metals (aluminum, arsenic [As], barium [Ba], cadmium, cobalt [Co], lead [Pb], manganese [Mn], molybdenum [Mo], nickel, and zinc [Zn]) in third trimester pregnant women (n?=?212) and their children at 8–14 years of age (n?=?250). Demographic factors (child sex, age, socioeconomic status, and maternal education), body mass index (BMI) z-score, and child personal care product use in the 24?h prior to urine collection were examined as predictors of urinary metal concentrations. Metals were detected in 80–100% of urine samples, with significant differences in maternal versus childhood levels. However, metal concentrations were not strongly correlated within or between time points. In linear regression models including all demographic characteristics, BMI z-score, and specific gravity, age was associated with higher Co (6% [95% CI: 2, 10]), while BMI z-score was associated with lower Mo (-6% [95% CI: -11, -1). In addition, significantly higher metal concentrations were observed among users of colored cosmetics (Mo: 42% [95% CI: 1, 99]), deodorant (Ba: 28% [3, 58]), hair spray/hair gel (Mn: 22% [3, 45]), and other toiletries (As: 50% [9, 108]), as well as with an increasing number of personal care products used (As: 7% [3, 11]) after adjustment for child sex, age, total number of products used, and specific gravity. However, significantly lower metal concentrations were noted for users of hair cream (As and Zn: -20% [-36, -2] and -21% [-35, -2], respectively), shampoo (Pb: -40% [-62, -7]), and other hair products (Pb: -44% [-65, -9]). We found that personal care product use may be a predictor of exposure to multiple metals among children. Further research is recommended to inform product-specific exposure source identification and related child health risk assessment efforts. 相似文献
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84.
We present a molecular phylogenetic study of the lichen genus Sticta focusing on Colombia, using the ITS fungal barcoding gene for a total of 370 ingroup OTUs, with 322 newly generated sequences. The topology resulting from a maximum likelihood approach does not support current species concepts in Sticta, which use a morphological concept, but in contrast shows that similar morphodemes evolved multiple times independently within the genus. As a consequence, currently applied names such as S. fuliginosa and S. weigelii comprise numerous (up to more than 20) unrelated species-level lineages, which can be distinguished also phenotypically using previously unrecognized characters such as lobe configuration, lobe surface structure, tomentum type, and anatomy of the basal membrane of the cyphellae. We conclude that the genus Sticta contains about four to five times the number of species currently recognized. In Colombia alone, approximately 150 species of Sticta are present. 相似文献
85.
Nonclinical pharmacokinetics and metabolism of EPZ‐5676, a novel DOT1L histone methyltransferase inhibitor 下载免费PDF全文
Aravind Basavapathruni Edward J. Olhava Scott R. Daigle Carly A. Therkelsen Lei Jin P. Ann Boriack‐Sjodin Christina J. Allain Christine R. Klaus Alejandra Raimondi Margaret Porter Scott Angelos Dovletoglou Victoria M. Richon Roy M. Pollock Robert A. Copeland Mikel P. Moyer Richard Chesworth Paul G. Pearson Nigel J. Waters 《Biopharmaceutics & drug disposition》2014,35(4):237-252
(2R,3R,4S,5R)‐2‐(6‐Amino‐9H‐purin‐9‐yl)‐5‐((((1r,3S)‐3‐(2‐(5‐(tert‐butyl)‐1H‐benzo[d]imidazol‐2‐yl)ethyl)cyclobutyl)(isopropyl)amino)methyl)tetrahydrofuran‐3,4‐diol (EPZ‐5676) is a novel DOT1L histone methyltransferase inhibitor currently in clinical development for the treatment of MLL‐rearranged leukemias. This report describes the preclinical pharmacokinetics and metabolism of EPZ‐5676, an aminonucleoside analog with exquisite target potency and selectivity that has shown robust and durable tumor growth inhibition in preclinical models. The in vivo pharmacokinetics in mouse, rat and dog were characterized following i.v. and p.o. administration; EPZ‐5676 had moderate to high clearance, low oral bioavailability with a steady‐state volume of distribution 2–3 fold higher than total body water. EPZ‐5676 showed biexponential kinetics following i.v. administration, giving rise to a terminal elimination half‐life (t1/2) of 1.1, 3.7 and 13.6 h in mouse, rat and dog, respectively. The corresponding in vitro ADME parameters were also studied and utilized for in vitro–in vivo extrapolation purposes. There was good agreement between the microsomal clearance and the in vivo clearance implicating hepatic oxidative metabolism as the predominant elimination route in preclinical species. Furthermore, low renal clearance was observed in mouse, approximating to fu‐corrected glomerular filtration rate (GFR) and thus passive glomerular filtration. The metabolic pathways across species were studied in liver microsomes in which EPZ‐5676 was metabolized to three monohydroxylated metabolites (M1, M3 and M5), one N‐dealkylated product (M4) as well as an N‐oxide (M6). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
86.
Maria Paz Garcia-Portilla Maria Teresa Bobes-Bascaran Maria Teresa Bascaran Pilar Alejandra Saiz Julio Bobes 《British journal of clinical pharmacology》2014,77(2):272-284
The aim of this review was to update and summarize the scientific knowledge on the long term outcomes of the different pharmacological treatment options for opioid dependence currently available and to provide a critical discussion on the different treatment options based on these results. We performed a literature search using the PubMed databases and the reference lists of the identified articles. Data from research show that the three pharmacological options reviewed are effective treatments for opioid dependence with positive long term outcomes. However, each one has its specific target population and setting. While methadone and buprenorphine are first line options, heroin-assisted treatment is a second line option for those patients refractory to treatment with methadone with concomitant severe physical, mental, social and/or functional problems. Buprenorphine seems to be the best option for use in primary care offices. The field of opioid dependence treatment is poised to undergo a process of reinforcement and transformation. Further efforts from researchers, clinicians and authorities should be made to turn new pharmacological options into clinical reality and to overcome the structural and functional obstacles that maintenance programmes face in combatting opioid dependence. 相似文献
87.
John E. Campbell Kevin W. Kuntz Sarah K. Knutson Natalie M. Warholic Heike Keilhack Tim J. Wigle Alejandra Raimondi Christine R. Klaus Nathalie Rioux Akira Yokoi Satoshi Kawano Yukinori Minoshima Hyeong-Wook Choi Margaret PorterScott Nigel J. Waters Jesse J. Smith Richard Chesworth Mikel P. Moyer RobertA. Copeland 《ACS medicinal chemistry letters》2015,6(5):491-495
88.
Dissecting virulence: systematic and functional analyses of a pathogenicity island 总被引:32,自引:0,他引:32 下载免费PDF全文
Deng W Puente JL Gruenheid S Li Y Vallance BA Vázquez A Barba J Ibarra JA O'Donnell P Metalnikov P Ashman K Lee S Goode D Pawson T Finlay BB 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(10):3597-3602
Bacterial pathogenicity islands (PAI) often encode both effector molecules responsible for disease and secretion systems that deliver these effectors to host cells. Human enterohemorrhagic Escherichia coli (EHEC), enteropathogenic E. coli, and the mouse pathogen Citrobacter rodentium (CR) possess the locus of enterocyte effacement (LEE) PAI. We systematically mutagenized all 41 CR LEE genes and functionally characterized these mutants in vitro and in a murine infection model. We identified 33 virulence factors, including two virulence regulators and a hierarchical switch for type III secretion. In addition, 7 potential type III effectors encoded outside the LEE were identified by using a proteomics approach. These non-LEE effectors are encoded by three uncharacterized PAIs in EHEC O157, suggesting that these PAIs act cooperatively with the LEE in pathogenesis. Our findings provide significant insights into bacterial virulence mechanisms and disease. 相似文献
89.
Similarities between the DNA replication initiators of Gram-negative bacteria plasmids (RepA) and eukaryotes (Orc4p)/archaea (Cdc6p) 下载免费PDF全文
Giraldo R Diaz-Orejas R 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(9):4938-4943
The proteins responsible for the initiation of DNA replication are thought to be essentially unrelated in bacteria and archaea/eukaryotes. Here we show that RepA, the initiator from the Pseudomonas plasmid pPS10, and the C-terminal domain of ScOrc4p, a subunit of Saccharomyces cerevisiae (Sc) origin recognition complex (ORC), share sequence similarities. Based on biochemical and spectroscopic evidence, these similarities include common structural elements, such as a winged-helix domain and a leucine-zipper dimerization motif. We have also found that ScOrc4p, as previously described for RepA-type initiators, interacts with chaperones of the Hsp70 family both in vitro and in vivo, most probably to regulate the assembly of active ORC. In evolutionary terms, our results are compatible with the recruitment of the same protein module for initiation of DNA replication by the ancestors of present-day Gram-negative bacteria plasmids, archaea, and eukaryotes. 相似文献
90.
Torralba MA Pérez-Calvo JI Pastores GM Cenarro A Giraldo P Pocoví M 《Blood cells, molecules & diseases》2001,27(2):489-495
BACKGROUND: Gaucher disease is an autosomal recessive disorder resulting from mutations in the glucocerebrosidase gene (GBA). The lack of full genotype/phenotype correlation complicates counseling regarding clinical outcome and treatment recommendations. SUBJECTS AND METHODS: Several mutations in the human beta-glucosidase gene associated with Gaucher disease in 16 Spanish families were identified utilizing a combination of methods: enzymatic restriction, PCR-SSCP, and sequence analyses. Expression studies were performed following the introduction of the mutagenized human acid beta-glucosidase cDNA into COS-1 cells, and the residual enzyme activities of the mutant protein were measured and compared with the normal cDNA. RESULTS: The identified mutations and corresponding residual enzyme activities of the expressed protein are as follows: c.517A>C (T134P), 1%; c.721G>A (G202R), 17%; c.1090G>T (G325W), 13.9%; c.1093G>A (E326K), 26%; c.1208G>A (S364N), 4.1%; c.1226A>G (N370S), 17,8%; c.1246G>A (G377S), 17.6%; c.1289C>T (P391L), 8.5%; c.1448T>C (L444P), 3%; and c.1504C>T (R463C), 24.5%. CONCLUSIONS: Site-directed mutagenesis and expression in COS-1 cells are useful methods to increase our understanding of causality in Gaucher disease and the correlation between disease severity, gene defects, and residual enzyme activity. Our study demonstrates the functional consequences of the identified human beta-glucosidase mutations (T134P, S364N, G377S, P391L, and G325W) and provide evidence for the molecular and biochemical basis of Gaucher disease, among patients of Spanish ancestry. 相似文献