The tunica media of a blood vessel wall is modeled as a heterogeneous medium composed of a periodic array of cylindrical smooth muscle cells and a continuous interstitial fluid phase of proteoglycan and collagen fibers. By applying Brinkman's model to describe the behavior of the interstitial flow, we obtain an analytical solution for the transmural flow field through the periodic array of smooth muscle cells in the form of a power series, making it possible to compute the convection of solutes in the interstitial phase. With reaction of solutes at the surface of smooth muscle cell membranes being treated as boundary conditions and the diffusion of species being limited to the interstitial fluid phase only, mass transfer in the media of blood vessel walls is simulated numerically using Cray supercomputers. It is found that the Sherwood number (the dimensionless mass-transfer coefficient) is not only constant for all interior smooth muscle cells but also minimally sensitive to changes of parameters controlling the relative rates of diffusion and convection in the interstitial fluid phase and the reaction on the smooth muscle cell surface. In addition, the Sherwood number is not very sensitive to changes in the volume fraction of smooth muscle cells. A homogeneous, one-dimensional model (effective-medium model) is also developed to predict the bulk concentration profile in the media, based on the equivalent properties of the effective medium derived from the heterogeneous medium. A comparison of results from the one-dimensional model and two-dimensional simulation is quite satisfactory for all practical ranges of parameters. It is also determined that, for a small molecule such as ATP, the mass transfer to the surface of smooth muscle cells is "reaction limited" as assumed previously in the literature, whereas, for a large molecule such as low-density lipoprotein, the mass transfer might not be reaction limited.

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Myelosuppression is one of the serious side effects of anticancer chemotherapeutic drugs that deteriorate the bodily functions of patients, thereby affecting the quality of life considerably. Prevention of myelosuppression in anticancer chemotherapy is an important research topic. A stabilized chemotherapy-induced myelosuppression animal model is necessary in experimental research. This study aimed to establish an optimized animal model of chemotherapy-induced bone marrow suppression. After C57BL/6 mice were treated with intermediate- and high-dose (25/50 mg/kg) cyclophosphamide (CTX) for 10 days, the body-weight, changes in thymus and spleen, number of white blood cells (WBCs), red blood cells (RBCs), and platelets (PLTs) and changes in bone marrow in the mice were systematically evaluated at the next 2, 7 and 14 days. Our results demonstrated that CTX treatments could significantly decrease the body-weight of mice, as well as the ratios of the weights of thymus and spleen to body-weight. The physiological structures of thymus and spleen were destroyed by CTX treatments. The number of WBCs and RBCs significantly declined after CTX treatments; however, the number of PLTs increased. Moreover, the expression of Sca1 in bone marrow cells decreased on Day 2 but increased on Day 14. The expression of CD34 decreased in bone marrow cells after CTX treatments. In conclusion, mice models, with high-dose CTX treatments for 10 days, can be an optimized animal model for chemotherapy-induced bone marrow suppression.

A new furanocoumarin, 5-methyl-8-(3-methylbut-2-enyl) furanocoumarin (1), together with seven known compounds, sterequinone C (2), cyclo(6,7-en-Pro-L-Phe) (3), bergapten, scopoletin, umbelliferone, 1,7-dihydroxyxanthone and 3,5-dimethoxybiphenyl, was isolated from the mangrove endophytic fungus, Penicillium sp. ZH16 obtained from the South China Sea. Their structures were determined by analysis of spectroscopic data. Compound 1 exhibited cytotoxicity against KB and KB(V)200 cells in vitro with IC(50) values 5 and 10 µg mL(-1), respectively.

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Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Compound 1 exhibited cytotoxicity against KB and KB V 200 cells with IC 50 values greater than 50 Pg/mL, respectively.

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A new polyketide, 2-(7′-hydroxyoxooctyl)-3-hydroxy-5-methoxybenzeneacetic acid ethyl ester (1), together with three known compounds dothiorelone A (2), B (3), and C (4) were isolated from the mangrove endophytic fungus Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Primary bioassays showed that 1 exhibited cytotoxicity against HEp-2 and HepG2 cells with IC 50 values of 25 and 30 μg/mL, respectively.Marine-derived fungi have proven to be a rich source of structurally unique and biologically active secondary metabolites [1]. In our search for new metabolites from marine-derived mangrove endophytic fungi from the South China Sea, we have isolated many significant new bioactive metabolites [2][3][4][5][6][7][8]. This paper reports the isolation and characterization of a new polyketide, 2-(7′-hydroxyoxooctyl)-3-hydroxy-5-methoxybenzeneacetic acid ethyl ester (1), and three known compounds dothiorelone A (2), B (3), and C (4) from the mangrove endophytic fungus Phomopsis sp. ZSU-H76 isolated from the stem of the mangrove tree Excoecaria agallocha from Dong Zai, Hainan, China. Cytotoxic effects of compound 1 against HEp-2 cells and HepG2 cells were first measured.The ethyl acetate extract of a fermentation broth of the fungus was repeatedly chromatographed on silica gel using gradient elution from petroleum to ethyl acetate to give compound 1 from the 15% ethyl acetate/petroleum fraction as a colorless oil. Compound