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Background  

Granulocyte colony-stimulating factor (G-CSF), a hematopoietic cytokine, was recently used to treat patients of acute myocardial infarction with beneficial effect. However, controversy exists as some patients developed re-stenosis and worsened condition post G-CSF delivery. This study presents a new disease model to study G-CSF induced cardiac thrombosis and delineate its possible mechanism. We used iron loading to mimic condition of chronic cardiac dysfunction and apply G-CSF to mice to test our hypothesis.  相似文献   
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The point-charge approximation, typically used by classical molecular mechanics force-fields, can be overcome by a multipolar expansion. For decades multipole moments were only used in the context of the rigid body approximation but recently it has become possible to combine multipolar electrostatics with molecular flexibility. The program DL_MULTI, which is derived from DL_POLY_2, includes efficient multipolar Ewald functionality up to the hexadecapole moment but the code is restricted to rigid bodies. The incorporation of flexibility into DL_MULTI would cause too large an impact on its architecture whereas the package DL_POLY_4 offers a more attractive and sustainable route to handle multipolar electrostatics. This package inherently handles molecular flexibility, which warrants sufficiently transferable atoms or atoms that are “knowledgeable” about their chemical environment (as made possible by quantum chemical topology and machine learning). DL_MULTI uses the spherical multipole formalism, which is mathematically more involved than the Cartesian one but which is more compact. DL_POLY_4 uses the computationally efficient method of smooth particle mesh Ewald (SPME) summation, which has also been parallellized by others. Therefore, combining the strengths of DL_POLY_4 and DL_MULTI poses the challenge of merging SPME with multipolar electrostatics by spherical multipole. In an effort to recast as clearly as possible the principles behind DL_MULTI, its key equations have been reformulated by the more streamlined route involving the algebra of complex numbers, and some of these equations’ peculiarities clarified. This article explores theoretically the repercussions of the merging of SPME with spherical multipole electrostatics (as implemented in DL_MULTI). Difficulties in design and implementation of possible future code are discussed.  相似文献   
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This investigation determined whether daily strenuous exercise would alter the progression and regression of an allogeneic lymphoid tumor in mice. We also determined whether exercise would alter the cellular composition and vascularity of the tumor. Female BALB/c mice (age 6-8 wk) were randomly assigned to sedentary control (Con) or daily exercised groups (EXH). EXH mice ran on a treadmill at incremental speeds (20-40 m/min) for 3 h or until fatigue. Each mouse was subcutaneously injected with 20 x 10(6) EL-4 lymphoma cells immediately after the first exercise bout (day 1) and run daily. Tumor volume was measured daily with calipers. In some experiments, mice were euthanized on days 5-10, 12, and 14. Tumors were excised and stained with hematoxylin and eosin or for Factor VIII-associated antigen using immunohistochemistry and analyzed in a blinded fashion under a light microscope. There was no significant treatment main effect found for tumor volumes. Interestingly, a significant treatment x time interaction was found, such that there was a 2-day delay in peak tumor volume and a more rapid tumor regression in EXH. Tumors isolated from Con exhibited significantly higher numbers of apoptotic bodies, blood vessels, macrophages, and neutrophils when compared with EXH. Intratumoral lymphocytes were higher in Con early in tumor growth but higher in EXH at peak tumor size. These data indicate that daily strenuous exercise may influence tumor growth by affecting the microenvironment of the tumor, resulting in a delay in tumor growth and a more rapid regression.  相似文献   
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This study examined olfactory sensory neuron morphology and physiological responsiveness in newly hatched sea lamprey, Petromyzon marinus L. These prolarvae hatch shortly after neural tube formation, and stay within nests for approximately 18 days, before moving downstream to silty areas where they burrow, feed and pass to the larval stage. To explore the possibility that the olfactory system is functioning during this prolarval stage, morphological and physiological development of olfactory sensory neurons was examined. The nasal cavity contained an olfactory epithelium with ciliated olfactory sensory neurons. Axons formed aggregates in the basal portion of the olfactory epithelium and spanned the narrow distance between the olfactory epithelium and the brain. The presence of asymmetric synapses with agranular vesicles within fibers in the brain, adjacent to the olfactory epithelium suggests that there was synaptic connectivity between olfactory sensory axons and the brain. Neural recordings from the surface of the olfactory epithelium showed responses following the application of L-arginine, taurocholic acid, petromyzonol sulfate (a lamprey migratory pheromone), and water conditioned by conspecifics. These results suggest that lampreys may respond to olfactory sensory input during the prolarval stage.  相似文献   
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The intense search for the “Holy Grail” of antifungal therapy can be observed today. The searches are not limited only to discovery of potential antifungal drugs, but also new therapeutic strategies involving the use of chemosensitizers to achieve synergistic effect or physicochemical factors inducing stress conditions in fungal cells. In this study was examined in vitro effectiveness of photodynamic antifungal strategy with methylene blue using a light beam with a wavelength equal to 635 nm toward the Trichophyton verrucosum susceptible and itraconazole- and/or fluconazole-resistant strains. Methylene blue used at concentration equal to 5 μg/mL and in the presence of 40 J/cm2 of light energy showed fungicidal effect toward the susceptible strains. However, for azole-resistant isolates, only the energy dose equal to 60 J/cm2 at 5 μg/mL of methylene blue allowed to kill the pathogen. This study confirms that methylene blue induced by red light has a definite inhibitory effect on zoophilic dermatophytes.  相似文献   
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