202 research outputs found

    Dynamics of individual Brownian rods in a microchannel flow

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    We study the orientational dynamics of heavy silica microrods flowing through a microfluidic channel. Comparing experiments and Brownian dynamics simulations we identify different particle orbits, in particular in-plane tumbling behavior, which cannot be explained by classical Jeffery theory, and we relate this behavior to the rotational diffusion of the rods. By constructing the full, three-dimensional, orientation distribution, we describe the rod trajectories and quantify the persistence of Jeffery orbits using temporal correlation functions of the Jeffery constant. We find that our colloidal rods lose memory of their initial configuration in about a second, corresponding to half a Jeffery period.Comment: 5 pages, 4 figure

    Protective effect of crude polysaccharide from Pao-TianXiong derived from monkshood, against chronic renal failure in mice

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    Purpose: To investigate the effect of crude polysaccharide isolated from pao-tian-xiong on chronic renal failure in mice, and its monosaccharide composition. Methods: Male Kunming mice were orally treated with adenine (211.5 mg/kg/day) for 7 days, followed by either crude polysaccharides (125, 250 or 500 mg/kg), or positive drug solution (jinguishenqi pill, 2000 mg/kg) for another 7 days (each group had 15 mice). Mice in normal and negative control groups were given saline. Mental and physical states, blood urine nitrogen (BUN) and serum creatinine (SCr), kidney morphological changes and organ indices were determined. Histopathological examination of spleen and kidney tissues was also performed. The monosaccharide composition of crude polysaccharide was determined by high-performance liquid chromatography (HPLC) and gas chromatography and mass spectrometry (GC-MS). Results: Compared with negative control group, serum BUN (6.71 mmol/L vs. 8.61 mmol/L) and Cr (107.74 vs. 113.39 Ī¼mol/L) were significantly decreased by the crude polysaccharide isolate (p < 0.05), whereas epididymis index (0.2556 vs. 0.2135 %) and seminal vesicle index (0.5547 vs. 0.3945 %) were increased (p < 0.05). Histopathological examination showed that injuries to kidney, spleen, testis and epididymis decreased significantly. The crude polysaccharides contained mainly glucose, rhamnose, arabinose, galactose, mannose, galacturonic acid, glucuronic acid and xylose, and their contents ranged from 0.7 to 65 %. Conclusion: These results suggest that the crude polysaccharides of Pao-tian-xiong ameliorates CRF symptoms in mice, thereby providing experimental evidence in support of its use as an anti-CRF drug

    Guizhi-jia-houpu-xingzi decoction attenuates ovalbumin-induced allergic asthma via regulation of Toll-like receptor signal pathway

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    Purpose: To study the effect of Guizhi-jia-houpu-xingzi (GHX) on ovalbumin-induced allergic asthma in rats.Methods: An animal model of allergic asthma (AA) in rats was established by intraperitoneal injection (ip) of ovalbumin (OVA). Thereafter, GHX (375 mg/kg) was administered orally for 7 days. Pulmonary function, inflammatory cells, immunoglobulin E (Ig) E, interleukin-4 (IL)-4 and interferon-Ī³ (IFN)-Ī³ in serum and bronchoalveolar lavage fluids (BALF) were determined. Furthermore, mRNA expressions of Toll-like receptors (TLRs) signal pathway was determined using real time polymerase chain reaction PCR (q-RT-PCR).Results: GHX (375 mg/kg) significantly decreased respiratory rate (p < 0.01) and Penh value (p < 0.05) when compared with AA rats. The inflammatory cells (p < 0.01) and levels of IL-4 (p < 0.01) and IgE (p < 0.01) were significantly decreased by GHX treatment when compared with AA rats; whereas IFN-Ī³ (p < 0.05) was significantly increased. Furthermore, GHX significantly decreased the mRNA expressions of GATA binding protein (GATA)-3 (p < 0.01), TRL-2 (p < 0.01), TRL-4 (p < 0.01), myeloid differentiation factor 88 (MyD88) (p < 0.01), TNF receptor associated factor 6 (TRAF6) (p < 0.01) and Ī²-arrestin (p < 0.01) in lung tissues, relative to AA rats. However, GHX treatment led to significant up-regulation of mRNA expression of T-bet (p < 0.01).Conclusion: These results demonstrate that GHX possesses a potential for treating allergic asthma via regulation of Toll-like receptor (TLR) signal pathway. They also provide a scientific basis for the probable use of GHX in clinical treatment of allergic diseases in future.Keywords: Guizhi-jia-houpu-xingzi decoction, Ovalbumin, Allergic asthma, Toll-like recepto

    A random walk description of the heterogeneous glassy dynamics of attracting colloids

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    We study the heterogeneous dynamics of attractive colloidal particles close to the gel transition using confocal microscopy experiments combined with a theoretical statistical analysis. We focus on single particle dynamics and show that the self part of the van Hove distribution function is not the Gaussian expected for a Fickian process, but that it reflects instead the existence, at any given time, of colloids with widely different mobilities. Our confocal microscopy measurements can be described well by a simple analytical model based on a conventional continuous time random walk picture, as already found in several other glassy materials. In particular, the theory successfully accounts for the presence of broad tails in the van Hove distributions that exhibit exponential, rather than Gaussian, decay at large distance.Comment: 13 pages, 5 figs. Submitted to special issue "Classical and Quantum Glasses" of J. Phys.: Condens. Matter; v2: response to refere

    And\^o dilations for a pair of commuting contractions: two explicit constructions and functional models

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    One of the most important results in operator theory is And\^o's \cite{ando} generalization of dilation theory for a single contraction to a pair of commuting contractions acting on a Hilbert space. While there are two explicit constructions (Sch\"affer \cite{sfr} and Douglas \cite{Doug-Dilation}) of the minimal isometric dilation of a single contraction, there was no such explicit construction of an And\^o dilation for a commuting pair (T1,T2)(T_1,T_2) of contractions, except in some special cases \cite{A-M-Dist-Var, D-S, D-S-S}. In this paper, we give two new proofs of And\^o's dilation theorem by giving both Sch\"affer-type and Douglas-type explicit constructions of an And\^o dilation with function-theoretic interpretation, for the general case. The results, in particular, give a complete description of all possible factorizations of a given contraction TT into the product of two commuting contractions. Unlike the one-variable case, two minimal And\^o dilations need not be unitarily equivalent. However, we show that the compressions of the two And\^o dilations constructed in this paper to the minimal dilation spaces of the contraction T1T2T_1T_2, are unitarily equivalent. In the special case when the product T=T1T2T=T_1T_2 is pure, i.e., if Tāˆ—nā†’0T^{* n}\to 0 strongly, an And\^o dilation was constructed recently in \cite{D-S-S}, which, as this paper will show, is a corollary to the Douglas-type construction. We define a notion of characteristic triple for a pair of commuting contractions and a notion of coincidence for such triples. We prove that two pairs of commuting contractions with their products being pure contractions are unitarily equivalent if and only if their characteristic triples coincide. We also characterize triples which qualify as the characteristic triple for some pair (T1,T2)(T_1,T_2) of commuting contractions such that T1T2T_1T_2 is a pure contraction.Comment: 24 page

    In silico screening of anti-inflammatory constituents with good drug-like properties from twigs of Cinnamomum cassia based on molecular docking and network pharmacology

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    Purpose: To investigate by in silico screening the anti-inflammatory constituents of Cinnamomum cassia twigs. Methods: Information on the constituents of C. cassia twigs was retrieved from the online Traditional Chinese Medicines (TCM) database and literature. Inflammation-related target proteins were identified from DrugBank, Online Mendelian Inheritance in Man (OMIM), Therapeutic Target Database (TTD), Genetic Association Database (GAD), and PharmGKB. The identified compounds were filtered by Lipinskiā€™s rules with Discovery Studio software. The ā€œLibdockā€ module was used to perform molecular docking; LibdockScores and default cutoff values for hydrogen bonds and van der Waals interactions were recorded. LibdockScores between the prototype ligand and target protein were set as the threshold; compounds with higher LibdockScores than threshold were regarded as active compounds. Cytoscape software was used to construct active constituent-target protein interaction networks. Results: Sixty-nine potential inflammatory constituents with good drug-like properties in C. cassia twigs were screened in silico based on molecular docking and network pharmacology analysis. JAK2, mPEGS-1, COX-2, IL-1Ī², and PPARĪ³ were considered the five most important target proteins. Compounds such as methyl dihydromelilotoside, hierochin B, dihydromelilotoside, dehydrodiconiferyl alcohol, balanophonin, phenethyl (E)-3-[4-methoxyphenyl]-2-propenoate, quercetin, and luteolin each interacted with more than six of the selected target proteins. Conclusion: C. cassia twigs possess active compounds with good drug-like properties that can potentially be developed to treat inflammation with multi-components on multi-targets

    Effects of fully open-air [CO2] elevation on leaf photosynthesis and ultrastructure of Isatis indigotica Fort

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    Traditional Chinese medicine relies heavily on herbs, yet there is no information on how these herb plants would respond to climate change. In order to gain insight into such response, we studied the effect of elevated [CO2] on Isatis indigotica Fort, one of the most popular Chinese herb plants. The changes in leaf photosynthesis,chlorophyll fluorescence, leaf ultrastructure and biomass yield in response to elevated [CO2] (550619 mmol molā€“1) were determined at the Free-Air Carbon dioxide Enrichment (FACE) experimental facility in North China. Photosynthetic ability of I. indigotica was improved under elevated [CO2]. Elevated [CO2] increased net photosynthetic rate (PN), water use efficiency (WUE) and maximum rate of electron transport (Jmax) of upper most fully-expended leaves, but not stomatal conductance (gs), transpiration ratio (Tr) and maximum velocity of carboxylation (Vc,max). Elevated [CO2] significantly increased leaf intrinsic efficiency of PSII (Fvā€™/Fmā€™) and quantum yield of PSII(WPSII), but decreased leaf non-photochemical quenching (NPQ), and did not affect leaf proportion of open PSII reaction centers (qP) and maximum quantum efficiency of PSII (Fv/Fm). The structural chloroplast membrane, grana layer and stroma thylakoid membranes were intact under elevated [CO2], though more starch grains were accumulated within the chloroplasts than that of under ambient [CO2]. While the yield of I. indigotica was higher due to the improved photosynthesis under elevated [CO2], the content of adenosine, one of the functional ingredients in indigowoad root was not affected

    The role of Th17 cells in endocrine organs: Involvement of the gut, adipose tissue, liver and bone

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    T Helper 17 (Th17) cells are adaptive immune cells that play myriad roles in the body. Immuneā€“endocrine interactions are vital in endocrine organs during pathological states. Th17 cells are known to take part in multiple autoimmune diseases over the years. Current evidence has moved from minimal to substantial that Th17 cells are closely related to endocrine organs. Diverse tissue Th17 cells have been discovered within endocrine organs, including gut, adipose tissue, liver and bone, and these cells are modulated by various secretions from endocrine organs. Th17 cells in these endocrine organs are key players in the process of an array of metabolic disorders and inflammatory conditions, including obesity, insulin resistance, nonalcoholic fatty liver disease (NAFLD), primary sclerosing cholangitis (PSC), osteoporosis and inflammatory bowel disease (IBD). We reviewed the pathogenetic or protective functions played by Th17 cells in various endocrine tissues and identified potential regulators for plasticity of it. Furthermore, we discussed the roles of Th17 cells in crosstalk of gut-organs axis
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