6,973 research outputs found

    Transient receptor potential canonical type 3 channels control the vascular contractility of mouse mesenteric arteries

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    Transient receptor potential canonical type 3 (TRPC3) channels are non-selective cation channels and regulate intracellular Ca2+ concentration. We examined the role of TRPC3 channels in agonist-, membrane depolarization (high K+)-, and mechanical (pressure)-induced vasoconstriction and vasorelaxation in mouse mesenteric arteries. Vasoconstriction and vasorelaxation of endothelial cells intact mesenteric arteries were measured in TRPC3 wild-type (WT) and knockout (KO) mice. Calcium concentration ([Ca2+]) was measured in isolated arteries from TRPC3 WT and KO mice as well as in the mouse endothelial cell line bEnd.3. Nitric oxide (NO) production and nitrate/nitrite concentrations were also measured in TRPC3 WT and KO mice. Phenylephrine-induced vasoconstriction was reduced in TRPC3 KO mice when compared to that of WT mice, but neither high K+- nor pressure-induced vasoconstriction was altered in TRPC3 KO mice. Acetylcholine-induced vasorelaxation was inhibited in TRPC3 KO mice and by the selective TRPC3 blocker pyrazole-3. Acetylcholine blocked the phenylephrine-induced increase in Ca2+ ratio and then relaxation in TRPC3 WT mice but had little effect on those outcomes in KO mice. Acetylcholine evoked a Ca2+ increase in endothelial cells, which was inhibited by pyrazole-3. Acetylcholine induced increased NO release in TRPC3 WT mice, but not in KO mice. Acetylcholine also increased the nitrate/nitrite concentration in TRPC3 WT mice, but not in KO mice. The present study directly demonstrated that the TRPC3 channel is involved in agonist-induced vasoconstriction and plays important role in NO-mediated vasorelaxation of intact mesenteric arteries.Fil: Yeon, Soo-In. Yonsei University College of Medicine; Corea del SurFil: Kim, Joo Young. Yonsei University College Of Medicine; . Yonsei University College of Medicine; Corea del SurFil: Yeon, Dong-Soo. Kwandong University College of Medicine; Corea del SurFil: Abramowitz, Joel. National Institute of Environmental Health Sciences; Estados UnidosFil: Birnbaumer, Lutz. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. National Institute of Environmental Health Sciences; Estados UnidosFil: Muallem, Shmuel. National Institutes of Health; Estados UnidosFil: Lee, Young-Ho. Yonsei University College of Medicine; Corea del Su

    Regular Schur labeled skew shape posets and their 0-Hecke modules

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    Assuming Stanley's PP-partition conjecture holds, the regular Schur labeled skew shape posets with underlying set {1,2,…,n}\{1,2,\ldots, n\} are precisely the posets PP such that the PP-partition generating function is symmetric and the set of linear extensions of PP, denoted ΣL(P)\Sigma_L(P), is a left weak Bruhat interval in the symmetric group Sn\mathfrak{S}_n. We describe the permutations in ΣL(P)\Sigma_L(P) in terms of reading words of standard Young tableaux when PP is a regular Schur labeled skew shape poset, and classify ΣL(P)\Sigma_L(P)'s up to descent-preserving isomorphism as PP ranges over regular Schur labeled skew shape posets. The results obtained are then applied to classify the 00-Hecke modules MP\mathsf{M}_P associated with regular Schur labeled skew shape posets PP up to isomorphism. Then we characterize regular Schur labeled skew shape posets as the posets whose linear extensions form a dual plactic-closed subset of Sn\mathfrak{S}_n. Using this characterization, we construct distinguished filtrations of MP\mathsf{M}_P with respect to the Schur basis when PP is a regular Schur labeled skew shape poset. Further issues concerned with the classification and decomposition of the 00-Hecke modules MP\mathsf{M}_P are also discussed.Comment: 44 page

    In Vitro Chemosensitivity Using the Histoculture Drug Response Assay in Human Epithelial Ovarian Cancer

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    The choice of chemotherapeutic drugs to treat patients with epithelial ovarian cancer has not depended on individual patient characteristics. We have investigated the correlation between in vitro chemosensitivity, as determined by the histoculture drug response assay (HDRA), and clinical responses in epithelial ovarian cancer. Fresh tissue samples were obtained from 79 patients with epithelial ovarian cancer. The sensitivity of these samples to 11 chemotherapeutic agents was tested using the HDRA method according to established methods, and we analyzed the results retrospectively. HDRA showed that they were more chemosensitive to carboplatin, topotecan and belotecan, with inhibition rates of 49.2%, 44.7%, and 39.7%, respectively, than to cisplatin, the traditional drug of choice in epithelial ovarian cancer. Among the 37 patients with FIGO stage Ⅲ/Ⅳ serous adenocarcinoma who were receiving carboplatin combined with paclitaxel, those with carboplatin-sensitive samples on HDRA had a significantly longer median disease-free interval than patients with carboplatin- resistant samples (23.2 vs. 13.8 months, p<0.05), but median overall survival did not differ significantly (60.4 vs. 37.3 months, p=0.621). In conclusion, this study indicates that HDRA could provide useful information for designing individual treatment strategies in patients with epithelial ovarian cancer

    Nucleon cosmological constant term and flavor structure of the gravitational form factors

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    The gravitational form factors furnish information on the mechanics of the nucleon. It is essential to compute the generalized isovector-vector form factors to examine the flavor structure of the gravitational form factors. The flavor-decomposed form factors reveal the internal structure of the nucleon. The up quark dominates over the down quark for the mass and spin of the nucleon, whereas the down quark takes over the up quark for the DD-term form factor. We investigate for the first time the isovector cosmological constant term of the nucleon and its physical implications. The flavor-decomposed cosmological constant terms of the nucleon unveil how the up-quark contribution is exactly canceled by the down-quark contribution inside a nucleon within the framework of the pion mean-field approach. While the nucleon cosmological constant term does not contribute to the nucleon mass, its flavor structure sheds light on how the strong force fields due to the cosmological constant term characterize the stability of the nucleon.Comment: 7 pages and 4 figures. The text was improved and extende

    Gravitational form factors of the baryon octet with flavor SU(3) symmetry breaking

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    We investigate the gravitational form factors of the baryon octet within the framework of the SU(3) chiral quark-soliton model, considering the effects of flavor SU(3) symmetry breaking, and the corresponding energy-momentum tensor distributions. We examine the effects of flavor SU(3) symmetry breaking to the mass, angular momentum, pressure, and shear force distributions of the baryon octet. We first find that a heavier baryon is energetically more compact than a lighter one. For the spin distributions of the baryon octet, they are properly normalized to their spins and are decomposed into the flavor-singlet axial charge and the orbital angular momentum even when the flavor SU(3) symmetry is broken. While the effects of the flavor SU(3) symmetry breaking differently contribute to the angular momentum distributions for the octet baryons, they are found to be rather small. The spin and orbital angular momentum almost equally contribute to the angular momentum distributions for the octet baryons. We also estimate the effects of the flavor SU(3) symmetry breaking to the pressure and shear force distributions. Interestingly, even if we include the effects of the SU(3) flavor symmetry breaking, the shear force distributions are kept to be positive over rr. It indicates that the Polyakov & Schweitzer local stability condition is kept to be intact with the flavor SU(3) symmetry broken. Lastly, we discuss how much the gravitational form factors vary with the effects of flavor SU(3) symmetry breaking considered.Comment: 27 pages, 8 figure

    Spin-orbit correlations in the nucleon in the large-NcN_{c} limit

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    We study the twist-3 spin-orbit correlations of quarks described by the nucleon matrix elements of the parity-odd rank-2 tensor QCD operator (the parity-odd partner of the QCD energy-momentum tensor). Our treatment is based on the effective dynamics emerging from the spontaneous breaking of chiral symmetry and the mean-field picture of the nucleon in the large-NcN_c limit. The twist-3 QCD operators are converted to effective operators, in which the QCD interactions are replaced by spin-flavor-dependent chiral interactions of the quarks with the pion field. We compute the nucleon matrix elements of the twist-3 effective operators and discuss the role of the chiral interactions in the spin-orbit correlations. We derive the first-quantized representation in the mean-field picture and develop a quantum-mechanical interpretation. The chiral interactions give rise to new spin-orbit couplings and qualitatively change the correlations compared to the quark model picture. We also derive the twist-3 matrix elements in the topological soliton picture where the quarks are integrated out (skyrmion). The methods used here can be extended to other QCD operators describing higher-twist nucleon structure and generalized parton distributions.Comment: 21 pages, 4 figure
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