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Traditional Chinese medicine (TCM) plays a systemic role in disease treatment, targeting multiple etiological factors simultaneously. Based on clinical experience, rhubarb and Salvia miltiorrhiza are commonly prescribed together for the treatment of chronic kidney disease (CKD) and have been proven to be very effective. However, the rationale of the combination remains unclear. The major active ingredients of these two herbs are rhein (RH) and danshensu (DSS), respectively. The aim of this paper is to investigate the renoprotective effects of RH and DSS in vitro and in vivo, and the underlying mechanism. A total of 5/6 nephrectomy rats and HK-2 cells were subjected to chronic renal injury. The combination of RH and DSS conferred a protective effect, as shown by a significant improvement in the renal function, blood supply, and fibrotic degree. Proinflammatory cytokines and adhesion molecules were suppressed by RH and DSS through NK-κB signaling. The combination also inhibited apoptosis by up-regulating Bcl-2 and down-regulating Bax. Inhibiting the TGF-β/Smad3 pathway was at least in part involved in the antifibrotic mechanism of the combination treatment of RH and DSS. This study demonstrates for the first time the renoprotective effect and the mechanism of RH and DSS combination on chronic renal injury. It could provide experimental evidence to support the rationality of the combinatorial use of TCM in clinical practices.

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The vibronic profiles of one-photon absorption spectra of dioxaborine heterocycles in gas phase and solution have been calculated at the Hartree-Fock and density-functional-theory levels. The polarizable continuum model has been applied to simulate the solvent effect, while the linear coupling model is used to compute the Franck-Condon and Herzberg-Teller contributions. It is found that a good agreement between theory and experiment can be achieved when the solvent effect and electron correlation are taken into account simultaneously. For the first excited charge-transfer state, the maximum of its Herzberg-Teller profile is blueshifted from that of the Franck-Condon profile. The shifted energy is found to be around 0.2 eV, which agrees well with the measured energy difference between two- and one-photon absorptions of the first excited state.

PET imaging plays an important role in scientific and clinical measurement of biochemical and physiological processes. Model-based PET image reconstruction such as the iterative expectation maximization algorithm seeking the maximum likelihood solution leads to increased noise. The maximum a posteriori (MAP) estimate removes divergence at higher iterations. However, a conventional smoothing prior or a total-variation (TV) prior in a MAP reconstruction algorithm causes over smoothing or blocky artifacts in the reconstructed images. We propose to use dictionary learning (DL) based sparse signal representation in the formation of the prior for MAP PET image reconstruction. The dictionary to sparsify the PET images in the reconstruction process is learned from various training images including the corresponding MR structural image and a self-created hollow sphere. Using simulated and patient brain PET data with corresponding MR images, we study the performance of the DL-MAP algorithm and compare it quantitatively with a conventional MAP algorithm, a TV-MAP algorithm, and a patch-based algorithm. The DL-MAP algorithm achieves improved bias and contrast (or regional mean values) at comparable noise to what the other MAP algorithms acquire. The dictionary learned from the hollow sphere leads to similar results as the dictionary learned from the corresponding MR image. Achieving robust performance in various noise-level simulation and patient studies, the DL-MAP algorithm with a general dictionary demonstrates its potential in quantitative PET imaging.

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The interest to design and synthesize organic molecules with ever larger two-photon absorption ͑TPA͒ cross sections at desirable wavelengths remains steadily growing. Theoretical simulations have played an important role in the development of these two-photon technologies. The majority of experimental and theoretical work has been mainly concerned with the property of a single molecule, while more recent work has also addressed intermolecular interactions, such as dielectric medium effects, on a two-photon absorption cross section of organic molecules, 1-5 but with the assumption that a single solute molecule is placed in the sea of solvent molecules not directly taking part in the actual twophoton process. The possible effects of molecular aggregation on two-photon absorption activities still seem to be left open for investigations.Aggregation is a common phenomenon that occurs in solutions of high concentration that is normally needed for real applications. Good nonlinear optical materials often possess electron donors or acceptors that can form aggregates through strong dipolar interaction or hydrogen bonding. This process has very strong destructive effects on the second order nonlinear optical property of dipolar molecules. 6 A recent molecular dynamics simulation study indicated that aggregation can even occur for octupolar molecules, such as the model system 1,3,5-triamino-2,4,6-trinitrobenzene ͑TATB͒, when it is dissolved in solution. 7 It was found that the dual action of the thermal motions of the atoms and the strong intermolecular interactions can alter the structure of the individual molecules and induce a permanent dipole moment in solution. The aggregation of TATB molecules is formed through strong H bonds between the molecules. 7 In this work, we focus our attention on the two-photon absorption of the octupolar molecule TATB, and study the aggregation effect on its TPA activity. Aggregates are represented by molecular dimers, which are taken from molecular dynamics simulations. Density functional response theory is applied to calculate the TPA cross sections of dimers of different conformations.The TATB monomer has been optimized at the hybrid density functional B3LYP level with the 6-31G * basis set using the GAUSSIAN03 program. 8 A snapshot with 64 TATB molecules and 512 chloroform molecules has been picked out from the molecular dynamic simulations that were reported in a previous study. 7 By inspecting the snapshots, one can find aggregates formed normally by several TATB molecules through hydrogen bonds. Due to the limitation of computational capacity, we will only study the behavior of dimers in this work. TPA cross sections of ten excited states have been calculated using response theory at the B3LYP level with a 6-31G * basis set as implemented in the DALTON ͑Ref. 9͒ quantum chemical program package. A lifetime of ⌫ = 0.1 eV is assumed for all calculated spectra. A comparative study of two-photon absorption properties of octupolar molecules has already been done by Beljonne et al. 10 The f...

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