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41.
《Bioorganic & medicinal chemistry letters》2014,24(6):1466-1471
This communication discusses the discovery of novel reverse tricyclic pyridones as inhibitors of Janus kinase 2 (JAK2). By using a kinase cross screening approach coupled with molecular modeling, a unique inhibitor–water interaction was discovered to impart excellent broad kinase selectivity. Improvements in intrinsic potency were achieved by utilizing a rapid library approach, while targeted structural changes to lower lipophilicity led to improved rat pharmacokinetics. This multi-pronged approach led to the identification of 31, which demonstrated encouraging rat pharmacokinetics, in vivo potency, and excellent off-target kinase selectivity. 相似文献
42.
Nadia Benaouag Michel Sardin Jazia Arrar Fatiha Bentahar 《Soil & Sediment Contamination》2018,27(5):408-425
The transient transport of naphthalene through low organic matter content soil columns was investigated in different water-saturation and flow conditions. Some parameters were tested as flow rate, column height, and water saturation conditions. The soil was a clayed sandy soil from the Algerian coast near Boumerdes. The organic carbon content was 0.13% and the main mineral components were quartz (88%), clays minerals (7%) and calcite (3%). The height of the packing of the soil column (5.1 cm in diameter) varied from 15 to 40 cm. Simultaneous step injections of inert tracer (calcium chloride) and naphthalene at 10 mg L?1 were performed. Tracer and naphthalene breakthrough curves (BTCs) were measured continuously by conductimetry and UV – 220 nm, respectively. The BTCs were simulated using the classical mixing cells in series with exchange model (MCE). In unsaturated conditions the comparison of the mean residence time of tracer BTCs with the geometrical pore volume gave us access to average water saturation along the column as a function of height. The higher the soil bed was, the higher the mean water saturation. The comparison of naphthalene distribution coefficients (Kd) in different flow conditions with the theoretical value from the Karickhoff law showed that in saturated conditions the obtained value was close to the theoretical one. In unsaturated conditions, the measured naphthalene Kd's were much lower than the theoretical value and correlated to the water saturation. 相似文献
43.
《Molecular & cellular proteomics : MCP》2023,22(1):100476
Cancer-derived extracellular vesicles (EVs) promote tumorigenesis, premetastatic niche formation, and metastasis via their protein cargo. However, the proteins packaged by patient tumors into EVs cannot be determined in vivo because of the presence of EVs derived from other tissues. We therefore developed a cross-species proteomic method to quantify the human tumor-derived proteome of plasma EVs produced by patient-derived xenografts of four cancer types. Proteomic profiling revealed individualized packaging of novel protein cargo, and machine learning accurately classified the type of the underlying tumor. 相似文献
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46.
Olga A. Grishina Irina V. Kirillova Olga E. Glukhova 《Computer methods in biomechanics and biomedical engineering》2016,19(3):297-305
The biomechanical model of human coronary arteries was modified for improving the quality of diagnosis and surgical treatment for coronary heart disease. The problem of hemodynamics in the left coronary artery with multivessel bed disease – 45% stenosis of the anterior descending branch and 75% stenosis of the circumflex branch – was particularly considered. Numerical simulation of the coronary arterial bypass of the main trunk was carried out to estimate the functional condition of the coronary arteries after restoring myocardial blood supply by surgery. 相似文献
47.
《Bioorganic & medicinal chemistry letters》2014,24(15):3302-3306
2-Arylethynyl-(N)-methanocarba adenosine 5′-methyluronamides containing rigid N6-(trans-2-phenylcyclopropyl) and 2-phenylethynyl groups were synthesized as agonists for probing structural features of the A3 adenosine receptor (AR). Radioligand binding confirmed A3AR selectivity and N6-1S,2R stereoselectivity for one diastereomeric pair. The environment of receptor-bound, conformationally constrained N6 groups was explored by docking to an A3AR homology model, indicating specific hydrophobic interactions with the second extracellular loop able to modulate the affinity profile. 2-Pyridylethynyl derivative 18 was administered orally in mice to reduce chronic neuropathic pain in the chronic constriction injury model. 相似文献
48.
《Journal of molecular recognition : JMR》2017,30(5)
Tolvaptan (TF), a selective arginine vasopressin V2 receptor antagonist, was approved by the Food and Drug Administration in 2009. This study mainly investigated the differences between the binding of TF with pepsin and trypsin by using a series of spectroscopy and molecular modeling methods. Thermodynamic parameters and molecular docking results suggested that the binding of TF to pepsin and trypsin were both spontaneous but driven by different forces. For pepsin, the binding was driven by hydrogen bonds and van der Waals forces; but for trypsin, it was driven by electrostatic forces and hydrophobic forces. The quenching mechanism between TF and pepsin and trypsin was investigated by fluorescence experiments and time‐resolved fluorescence spectroscopy. Synchronous fluorescence and 3‐dimensional fluorescence were used to investigate the micro‐environmental and conformational changes of pepsin and trypsin after the insertion of TF. In addition, activity‐measurement results showed that both the pepsin and trypsin activities increased with increasing TF concentration, which may help to understand the possible effect of TF on the digestion and absorption of nutrients in vivo. 相似文献
49.
The preferred mechanisms of racemization for three tris chelate complexes, Co(acac)3, Fe(phen)3 3+ and Fe[S2CN(CH2)4]3, were investigated by molecular modeling. The transition states for both a Bailar twist and a Rây-Dutt twist were considered; semi-empirical calculations (PM3) yielded activation energies. The preferred mechanism was the Bailar twist for Co(acac)3 and Fe[S2CN(CH2)4]3 with activation energies of 83.2 and 7.3 kcal mol−1, respectively, and the Rây-Dutt twist for Fe(phen)3 3+ with an activation energy of 114.4 kcal mol−1. These results are compared with those of geometrical models. 相似文献
50.
Charles A. Kunos Jeffrey M. Fabien John P. Shanahan Christine Collen Thierry Gevaert Kenneth Poels Robbe Van den Begin Benedikt Engels Mark De Ridder 《Journal of visualized experiments : JoVE》2015,(100)
Physicians considering stereotactic ablative body radiation therapy (SBRT) for the treatment of extracranial cancer targets must be aware of the sizeable risks for normal tissue injury and the hazards of physical tumor miss. A first-of-its-kind SBRT platform achieves high-precision ablative radiation treatment through a combination of versatile real-time imaging solutions and sophisticated tumor tracking capabilities. It uses dual-diagnostic kV x-ray units for stereoscopic open-loop feedback of cancer target intrafraction movement occurring as a consequence of respiratory motions and heartbeat. Image-guided feedback drives a gimbaled radiation accelerator (maximum 15 x 15 cm field size) capable of real-time ±4 cm pan-and-tilt action. Robot-driven ±60° pivots of an integrated ±185° rotational gantry allow for coplanar and non-coplanar accelerator beam set-up angles, ultimately permitting unique treatment degrees of freedom. State-of-the-art software aids real-time six dimensional positioning, ensuring irradiation of cancer targets with sub-millimeter accuracy (0.4 mm at isocenter). Use of these features enables treating physicians to steer radiation dose to cancer tumor targets while simultaneously reducing radiation dose to normal tissues. By adding respiration correlated computed tomography (CT) and 2-[18F] fluoro-2-deoxy-ᴅ-glucose (18F-FDG) positron emission tomography (PET) images into the planning system for enhanced tumor target contouring, the likelihood of physical tumor miss becomes substantially less1. In this article, we describe new radiation plans for the treatment of moving lung tumors. 相似文献