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Background: In our previous study, we found that the combination of a traditional Chinese medicine (TCM) and swimming could prevent atherosclerosis through a synergistic interaction. However, whether the combined application of active components from the fruit of Crataegus pinnatifida Bge. Var. major N.E. Br. and the root of Salvia miltiorrhiza Bge. (CPSM) and swimming has been effective in the prevention and treatment of focal cerebral infraction remained unclear. This work aimed to conduct detailed investigation on the joint effects of CPSM extract with swimming on focal cerebral infraction in rats and its underlying mechanisms.Method: A photochemical method of the combination of Rose Bengal (RB) injection and cold-light source irradiation was performed to establish the rat focal cerebral thrombosis model. The pathological changes of the brain were observed by a DCP-7030 laser multifunction machine, and the protein levels of von Willebrand factor (vWF), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) were detected by Western blotting. Blood samples were collected to assay tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-1), endothelin-1 (ET-1), 6-keto-prostaglandin F1α (6-keto-PGF1α), and thromboxane B2 (TXB2). Finally, the gene expression of t-PA, PAI-1, and ICAM-1 in human umbilical vein endothelial cells (HUVECs) stimulated by tumor necrosis factor-α (TNF-α) was assayed via real-time (RT) quantitative PCR (qPCR).Results: The joint effects of CPSM extract and swimming demonstrated significant interactions, which including increased blood perfusion, increased serum t-PA and 6-keto-PGF1α, decreased serum PAI-1 and TXB2, decreased protein levels of vWF, VCAM-1 and ICAM-1, and decreased ICAM-1 gene expression.Conclusion: This research demonstrated that the combined therapy of CP and SM extracts with swimming could prevent focal cerebral infraction through interactions on the regulation of vascular endothelial functions and inflammatory factors. It stresses the promising effects of the drugs and shear stress of blood flow in prevention and treatment of thrombosis. The mechanism may be related to regulating the protein expression of vWF, VCAM-1, and ICAM-1, and downregulating the gene expression of ICAM-1.

BACKGROUND Tissue channels as a part of microcirculation system have been proposed over three decades, playing an important role in fluid transportation as reported. Adventitia of inferior vena cava (IVC) is a typical hierarchical porous media with abundant tissue channels. Its fluid transportation behaviors attract massive research interest. However, the mechanism of the driving force and microstructure was lack of deep research. OBJECTIVE This study was to investigate the microstructural basis of fluid transportation within inferior vena cava (IVC). METHODS Rat IVC samples were extracted and fixed on a gelatin substrate. Four samples were randomly used as 4 cases: Case 1 with AFM loading and the fluorescent tracer adding; Case 2 with fluorescent tracer adding only; Case 3 with AFM loading only as the control group; Case 4 with no treatment. The movement of fluorescent tracer was observed by two-photon fluorescent microscope and analyzed by self-made Matlab program. The microscopic structure was characterized by high resolution TEM. RESULTS The fluorescent tracer in Case 1 exhibited faster and longer transportation comparing to other cases, while in Case 2 diffused normally following Fick's law. Case 3 with only AFM loading demonstrated that collagen bundles twisting along the fluid orientation, while the bundles in Case 4 with no treatment were straggling. The brush-like macromolecule structure of collagen microfibril was found on the bundle surfaces under TEM. CONCLUSIONS Transportation within loose connective tissues is observed ex vivo. AFM loading, as the mechanical stimulation resemblance to muscle constrictions and blood pulsations, can facilitate the transportation as the driving force. The brush-like glycosaminoglycan macromolecules on the surfaces of the collagen bundles can be considered as a type of hierarchical porous media, which might form the transport pathway for fluids. The possible mechanism was conducted regarding the conformation of the superficial macromolecule brushes.

Identifying effective targets induced by ECM stiffness is of critical importance for treating metastatic cancer diseases, which are followed by changes in the mechanical microenvironment in cancer cells. In this study, polyacrylamide hydrogel substrates with different stiffnesses were prepared and mRNA microarrays were performed to analyze the mRNA expression profiles in breast cancer cell line SK-BR-3 grown on different stiffness substrates. The results indicated that the expressions of 1831 genes were changed significantly in the SK-BR-3 cells on the different stiffness substrates. GO and KEGG pathway analyses of the differently expressed genes in five significant profiles annotated that the most significant pathways were cell cycle, ubiquitin mediated proteolysis RNA transport and pathways in cancer. Finally, the network of genes and gene interaction based on these differently expressed genes was established, and the phosphorylation of AKT and ERK, respectively the downstreams of the PI3K and Ras signal pathways, was further validated. The genes identified in this study may represent good therapeutic targets, and further study of these targets may help to increase our understanding of the mechanisms underlying the pathological processes and therapy for metastatic breast cancer disease.

Determination of erythrocyte flow velocity is a basic parameter for microcirculatory research. Generally, high speed digital recorder is applied to capture images for determination of erythrocyte velocity. Recently, we tried to use a consumer grade high-speed camera, Casio ZR100, to accomplish the objective. We find this economic device can be sometimes used as an alternative of the costly professional fast digital cameras. Wistar rats weighing between 70–80 g (n= 6) were involved for the pilot study. After the rat was anesthetized by 3% sodium pentobarbital (40 mg/kg), observation for mesentery microcirculation was prepared on the microscopic stage according to the routine procedure. Briefly, with rat in supine position, an abdominal incision of 1–1.5 cm was cut in the left lower quadrant, and the ileocecum was carefully pulled out and flatly placed on the transparent observation window. We then mounted Casio ZR100 (S/N 21001376F) on top of an extension tube on Olympus microscope BH-2 (Fig. 1). A photo lens (Olympus, 6.7×) and an image converter lens (50 mm focusing length) were accommodated inside the tube. A 10× objective was employed. The camera was mounted by a supporter which has X, Y, Z adjustment and angle-rotation possibility. The optical axis of the camera lens was carefully centered with the microscope by X, Y and Z adjustment to obtain a centered image of microcirculation at low range of zoom. A clear image at full zoom (18.8×) of micro-vessel could be focused by adjusting the Z position of the microscopic stage. Casio ZR100 supports high speed video at 240 (432× 320), 480 (224× 160) and 1000 (224× 64) fps. At each recording speed, we took microcirculation video for 1 or 2 seconds. We found that 1000 fps was not suitable for investigation due to the less pixels and insufficient lightening. The typical captured photos of mesentery microcirculation taken at 240 and 480 fps are presented in Fig. 2. The principle of erythrocyte velocity determination is directly based on the velocity definition, namely the travel distance of an erythrocyte divided by the travel duration. For a video taken at 240 fps, the

This work is to investigate the joint effect of extract from Shenlian (SL, the Chinese abbreviation for Radix Salviae miltiorrhizae and Andrographis paniculata) and swimming on atherosclerosis prevention and treatment. Atherosclerotic rat model was established by combining low shear stress by partial ligation of common carotid artery with afterwards feeding of a hyperlipotic diet. Sprague-Dawley rats after partial ligation of common carotid artery were allotted to a 3 × 3 factorial design with three levels of swimming (0, 1, and 2 hr per day) and three levels of SL extract (0, 2.56, and 5.12 g/kg once daily p.o.) for a total of 9 treatment groups. Then, the feeding of the hyperlipotic diet and the intervention of swimming and SL started at the same time, and lasted for 8 weeks. By the end, blood samples were collected to determine blood viscosity, hematocrit, blood lipids, MCP-1, NF-κB and NO levels. The common carotid arteries of the rats were harvested to investigate pathological changes. The animal model showed early sign of atherosclerosis according to the pathological findings. Joint effects of SL extract and swimming on preventing atherosclerosis appeared significantly: The combination of 1 hour swimming with 2.56 g/kg SL extract showed to be effective for lowering hematocrit, blood viscosity (at 10 s(-1) and 200 s(-1)) and low-density-lipoprotein (p < 0.001). Combined treatment of 2.56 g/kg SL extract with 2 hr swimming led to a synergistic decrease in serum level of MCP-1. As a single factor, SL extract (2.56 g/kg) alone could decrease serum levels of NF-κB significantly (p = 0.003). Swimming alone could decrease cholesterol, triacylglycerols level and increase high-density-lipoprotein. The study demonstrates the combined therapy of oral SL extract with swimming on inhibiting inflammatory factors, improving hemorheological parameters and lipoproteins in rat model of atherosclerosis. It highlights the promising effects of the drugs and shear stress of blood flow, the biomechenopharmacological means, for prevention of atherosclerosis.

Determination of erythrocyte flow velocity is an important parameter for microcirculatory research. We established an off-line method for determining erythrocyte velocity in microcirculation by computer- ized dynamic grey scale analysis. In principle, the method is based on the dual-slit photometric technique (1), and updated by software image analysis. We have applied high speed video recorder (FASTCAM- ultima APX, Photron, San Diego, CA) to capture digital images for mesentery microvessels in rat and rabbit since 2004. Each series of images during 10 seconds is captured at a speed of 2000 frames/s (fps) and is composed of images of 704 × 576 pixels with 256 grey levels. The video recording is converted to AVI format required by the software of ImagePro Plus (versions 4.5 or 5.0). The video is then inves- tigated frame by frame with the help of the "Sequencer Toolbar" in the menu of ImagePro Plus. The criterion for selecting an investigative segment in a capillary is that the erythrocyte flow keeps smooth and steady for 10 seconds at least. A reference line perpendicular to the axis of the capillary is setup to show the grey scale distribution along the radial line in the first frame of image. Then, a down-stream measuring line perpendicular to the axis of the capillary is setup with a distance about 10 µm apart from the reference line. The dynamic grey scale changes at the measuring line in the subsequent images are monitored frame by frame and the changes are compared with the grey scale distribution at the reference line in the first image (Figs 1 and 2). When the most matchable grey scale with the reference distribution is detected, the time interval for erythrocytes flowing from the reference line in the first frame to the measuring line in the "matchable" frame can be figured out by multiplying the frame difference by the duration between each frame. The erythrocyte velocity can be easily calculated by dividing the distance between the reference line and the measuring line by the time interval (Fig. 2).

In the Guidelines for measurement of blood viscosity and erythrocyte deformability by ICSH in 1986, it points out that the viscometer for hemorheology should ideally be able to operate over a wide range of shear conditions, and for a constant shear-rate viscometer a high-shear measurement at 200/second and a low-shear measurement at 1/second (or shear-rates approximating to these values if they are not attainable in the instrument used) should be made [1]. It also states that a high degree of instrument sensitivity is required for measuring viscosity at low shear. A suitable shear stress measuring range and a high degree sensitivity at low shear-rate are required for measuring blood viscosity. Unfortunately, many of the industrial viscometers do not meet the requirements [2]. In fact, the lowest measurable shear-stress is a critical parameter for a rotational blood viscometer. However, the criteria for evaluating shear measuring range and the lowest measurable shear-stress are not clearly described in the guidelines. We proposed double 5% criteria for the evaluation, i.e. less than 5% error in viscometry and less than 5% in coefficient of variation as “measurable” criteria. Recently, we experienced the criteria with a domestic rotational viscometer (anonym for avoiding possible conflicts in commercial interests). The viscometer is a shear-rate controlled rotational viscometer with double gap cylinder sensor designed for measuring blood and plasma viscosities. A suspending torsion strip is employed as the shearstress sensing element. The viscometer works in the shear-rate range of 1–220/second and shear-stress range of 10–2000 mPa according to the specifications described in the user’s manual. The sensor temperature is controlled at fixed 37 ± 0.5◦C. The required sample volume is 1.2 ml. We selected a number of standard oils (provided by the Chinese Academy of Metrology), including GBW(E)130251, GBW(E)130253, GBW(E)130254 and GBW(E)130255, for evaluation of the viscome

This research was aimed to investigate the anti-inflammatory mechanism of acetylharpagide extracted from Ajuga decumbens Thunb. Human umbilical vein endothelial cells (HUVECs) and human monocytic leukemia cell line THP-1 were employed as experimental materials. The MTT assay (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) was used to determine the safe dose range of acetylharpagide. TNF-α (20 ng/ml) was used to model THP-HUVECs adhesion/transmigration and trypsin was used to model wounding of HUVECs under controlled shear stress of 0.1 Pa and 0.2 Pa (5 h) by Bioflux1000 assays accordingly. Effects of acetylharpagide were dynamically monitored by microscopic time-lapse photography. Acetylharpagide within the concentration of 0-200 μM showed no sign of toxicity to HUVECs and THP-1. Acetylharpagide dose-dependently inhibited THP-1 adhesion to TNF-α activated HUVECs monolayer with an IC50 of 171 μM under static conditions. Acetylharpagide at 200 μM inhibited leukocyte adhesion and transmigration to HUVECs monolayer activated by TNF-α under 0.1 Pa shear stress (P < 0.05). The compound at 200 μM also inhibited HUVECs migration under 0.2 Pa in the wound healing model compared with the control group (P < 0.05). In conclusion, the anti-inflammatory effects of acetylharpagide are possibly related to inhibiting leukocytes adhesion and transmigration. Moreover, acetylharpagide also inhibits the endothelial cells migration notably, which might be the additional action responsible for its effect in reliving-chronic inflammatory progress.

Substrate stiffness has been proven to play a critical role in vitro tumor proliferation; however, pharmacological studies on antitumor drug screening are still routinely carried out in regular plastic culture plates. In the article, polydimethylsiloxane (PDMS) substrates with different stiffness (mimicking articular cartilage, collagenous bone and mammary tumor respectively) and plastic substrate were employed to establish the mechanical microenvironment for the in vitro drug screening platform. We studied the influences of stiffness on the responses of MCF-7 cells to typical antitumor drugs, cisplatin and taxol. Results showed that for both the treatment IC50 value to MCF-7 cells decreased significantly (p < 0.01) on the rigid substrate, indicating that MCF-7 cells on soft substrate have a resistance to cytotoxicity of antitumor drugs. The sensitivity of MCF-7 cells on rigid substrate to drug cytotoxicity was attributed to the increased cell cycle progression, implying that agents proven to be effective in vitro by conventional screening approach might be inefficient in a soft microenvironment in vivo. We conclude that stiffness of the substrates, as a critical mechanical factor, should be concerned for screening antitumor agents in vitro. As an extrapolation, the extensively used drug screening system needs to be revalued and redesigned.

Based on rotational viscometry of clotting, an approach for evaluation of antiplatelet drugs and anticoagulants was explored. Rat platelet rich plasma (PRP) and plate­ let poor plasma (PPP) were prepared. PRP and PPP were seperately incubated with and without drug (D), namely, PRP, PRP+D, PPP, and PPP+D. Recalcification of the sam­ ples were monitored by HAAKE Rotovisco RV20/CV100 at 0.3 s-l The inhibition of platelet involvement (IPI) and the inhibition of plasma clotting(IPC) were defined. According to three clotting parameters (tr, d~/dt, ~m), six inhibitions (3 IPI, 3 IPC) were obtained for evalu­ ating a drug. The preliminary investigation on heparin, pentoxifylline, aspirin, notoginseng saponins and alco­ hol indicated that the approach would be a promising mean for pharmacological and clinical practice.

International audience; This document, supported by both the International Society for Clinical Hemorheology and the European Society for Clinical Hemorheology and Microcirculation, proposes new guidelines for hemorheological methods used in experimental and clinical studies. It is based on a similar document entitled: "Guidelines for measurement of blood viscosity and erythrocyte deformability" published in 1986 by the Expert Panel on Blood Rheology of the International Committee for Standardization in Hematology. Recent methods, techniques and instruments, as well as new approaches to interpretation of results, are added to these new guidelines; wide spread adoption should improve comparability between hemorheological laboratories and increase the reliability of rheological tests.