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41.
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
42.
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
43.
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
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Mercedes Villegas Alicia Graciela Cid Cintia Alejandra Briones Analía Irma Romero Florencia Alejandra Pistán Elio Emilio Gonzo Juan Carlos Gottifredi José María Bermúdez 《Saudi Pharmaceutical Journal》2019,27(5):694-701
Controlled drug delivery aims to achieve an effective drug concentration in the action site for a desired period of time, while minimizing side effects. In this contribution, biodegradable poly(3-hydroxybutyrate) films were evaluated as a reservoir platform for dexamethasone controlled release. These systems were morphological and physicochemically characterized. In vitro release assays were performed for five different percentages of drug in the films and data were fitted by a mathematical model developed and validated by our research group. When the profiles were normalized, a single curve properly fitted all the experimental data. Using this unique curve, the dissolution efficiency (DE), the time to release a given amount of drug (tX%), and the mean dissolution time were calculated. Furthermore, the dissolution rate, the initial dissolution rate (a%) and the intrinsic dissolution rate were determined. The a% mean value was 1.968 × 10?2% released/min, t80% was about 14 days, and the DE was 59.6% at 14 days and 66.5% at 20 days. After 2 days, when approximately 40% of the drug was released, the dissolution rate decreased about 60% respect to the initial value. The poly(3-hydroxybutyrate) platforms behaved as an appropriate system to release and control the dexamethasone delivery, suggesting that they could be an alternative to improve drug therapy. 相似文献
46.
Alejandra Martínez-Trillos Margherita Maffioli Dolors Colomer Alberto Alvarez-Larrán Arturo Pereira Anna Angona Beatriz Bellosillo Francisco Cervantes 《Annals of hematology》2014,93(5):797-802
An association has been reported between a specific haplotype of the JAK2 gene, the homozygous 46/1 haplotype, and a predisposition to the development of chromosome Philadelphia-negative myeloproliferative neoplasms. Concerning myelofibrosis (MF), controversy remains on the relationship between the above JAK2 haplotype and the patients’ clinicohematological features and survival. Among 132 patients with MF (60 % primary MF, 20 % postpolycythemia vera MF, 20 % post-essential thrombocythemia MF; 59 % JAK2V617F positive) who were analyzed for the JAK2 46/1 haplotype, 29 were found to be homozygous and 53 heterozygous. The homozygous 46/1 haplotype was more often observed in JAK2V617F-positive patients (29.5 versus 11 %, p?=?0.012). Moreover, among JAK2V617F-positive patients, those who were homozygous for the 46/1 haplotype had a higher allele burden than the remainder (92 versus 48 %, p?=?0.0017). Overall, patients with homozygous 46/1 haplotype showed significantly higher hemoglobin values and higher leukocyte counts, but no association was seen with other clinicohematological features. Finally, no relationship was observed between the JAK2 46/1 haplotype and either the patients’ prognostic score or survival. 相似文献
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Foot-and-mouth disease virus (FMDV) antigenic-match between vaccine and field viruses has traditionally been estimated in vitro by computing the r1 value using virus neutralization test (VNT) or ELISA titers. In this study we compared the accuracy in predicting cross-protection between the r1 value estimated by VNT and two recently developed tests that measure IgG subtypes and avidity. Data analyzed consisted of 64 serum samples from FMDV A24/Cruzeiro vaccinated bovines challenged with the heterologous A/Argentina/2001 strain and evaluated for podal generalization. We computed the tests sensitivity (Se), specificity (Sp), and receiving operating characteristics (ROC) curve. The heterologous IgG1/IgG2 ratio was the most accurate test (Se = 0.71, Sp = 0.98), followed by heterologous IgG1 (Se = 0.53, Sp = 0.96), VNT (Se = 0.47, Sp = 1.00), whereas r1 accuracy was substantially low (Se = 0.41, Sp = 0.81). Because sensitivity of individual tests was limited, we argue that two or more of the tests should be used in combination to produce accurate estimates of protection. 相似文献
49.
María Julieta Russo Mónica Iturry María Alejandra Sraka Leonardo Bartoloni Cristóbal Carnero Pardo Ricardo Francisco Allegri 《The Clinical neuropsychologist》2014,28(5):826-840
Phototest is a simple, easy and very brief test with theoretical advantages over available dementia screening tests in Spain. The objective of this study was to estimate the diagnostic accuracy of the Phototest for cognitive impairment and dementia and to compare it with that of the MMSE and the Clock Drawing Test (CDT) in an Argentine population. A phase II cross-sectional study of diagnostic tests evaluation was performed in a sample of 30 controls, 61 with amnestic mild cognitive impairment (a-MCI), and 56 with mild Alzheimer type dementia (DAT). The diagnostic accuracy (DA) was assessed in relation to the clinical diagnosis by calculating the area under the ROC curve (UAC), Sensitivity (Sn), and Specificity (Sp).The DA of the Phototest for a-MCI and DAT (0.93 and 0.97 [UAC]) was higher than that of the MMSE and the CDT. The cut-off points of 27/28 for DAT (Sn = 89.29 [78.1–96.0], Sp = 96.67 [82.8–99.9]) and 30/31 for a-MCI (Sn = 85.25 [73.8–93.0], Sp = 90.00 [73.5–97.9]) maximized the sum of Sn and Sp. Phototest correlates significantly with MMSE and CDT. The Phototest is an efficient instrument for the detection of mild dementia or MCI, with good accuracy and good correlation with tests measuring overall cognitive impairment. 相似文献
50.
Cristián Biscayart María Eugenia Pérez Carrega Sandra Sagradini Ángela Gentile Daniel Stecher Tomás Orduna Silvia Bentancourt Salvador García Jiménez Luis Pedro Flynn Gabriel Pirán Arce María Andrea Uboldi Laura Bugna María Alejandra Morales Clara Digilio Cintia Fabbri Delia Enría Máximo Diosque Carla Vizzotti 《Vaccine》2014