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Preferential localization of a vesicular monoamine transporter to dense core vesicles in PC12 cells.
Neurons and endocrine cells have two types of secretory vesicle that undergo regulated exocytosis. Large dense core vesicles (LDCVs) store neural peptides whereas small clear synaptic vesicles store classical neurotransmitters such as acetylcholine, gamma-aminobutyric acid (GABA), glycine, and glutamate. However, monoamines differ from other classical transmitters and have been reported to appear in both LDCVs and smaller vesicles. To localize the transporter that packages monoamines into secretory vesicles, we have raised antibodies to a COOH-terminal sequence from the vesicular amine transporter expressed in the adrenal gland (VMAT1). Like synaptic vesicle proteins, the transporter occurs in endosomes of transfected CHO cells, accounting for the observed vesicular transport activity. In rat pheochromocytoma PC12 cells, the transporter occurs principally in LDCVs by both immunofluorescence and density gradient centrifugation. Synaptic-like microvesicles in PC12 cells contain relatively little VMAT1. The results appear to account for the storage of monoamines by LDCVs in the adrenal medulla and indicate that VMAT1 provides a novel membrane protein marker unique to LDCVs
Melatonin reduced volume of cerebral infarct induced by photothrombosis in wild-type mice, not in Cyclooxygenase-1 gene knockout mice
Cyclooxygenase (COX) is crucial in inflammation and plays important role in cerebral ischemia. Anti-inflammatory effects of melatonin have been verified in previous studies. In this study, cerebral blood flow (CBF) was monitored during operation, infarct volume (IFV) was determined with 5-triphenyltetrazolium chloride (TTC) staining and MR image, and neurological functions were evaluated with turn in an alley and fall pole test in both COX-1-gene knockout and wide-type mice with or without melatonin administration 3 days after photothrombosis. CBF reduction, IFV and neurological deficits were not significantly different in COX-1 wild-type and COX-1 knockout mice. Melatonin (15 mg/kg) intraperitoneal injection decreased the CBF reduction, IFV and the latency to turn in an alley in COX-1 wide-type mice, whereas the neuroprotective effect of melatonin was attenuated in COX-1 knockout mice. We concluded that melatonin reduced susceptibility to photothrombotic stroke. COX-1 gene knockout does not alter the susceptibility to cerebral ischemia caused by photothrombosis. COX-1 plays an important role in the pathway of the protection of melatonin.published_or_final_versio
Log-Harnack Inequality for Stochastic Burgers Equations and Applications
By proving an -gradient estimate for the corresponding Galerkin
approximations, the log-Harnack inequality is established for the semigroup
associated to a class of stochastic Burgers equations. As applications, we
derive the strong Feller property of the semigroup, the irreducibility of the
solution, the entropy-cost inequality for the adjoint semigroup, and entropy
upper bounds of the transition density
Effective action in a higher-spin background
We consider a free massless scalar field coupled to an infinite tower of
background higher-spin gauge fields via minimal coupling to the traceless
conserved currents. The set of Abelian gauge transformations is deformed to the
non-Abelian group of unitary operators acting on the scalar field. The gauge
invariant effective action is computed perturbatively in the external fields.
The structure of the various (divergent or finite) terms is determined. In
particular, the quadratic part of the logarithmically divergent (or of the
finite) term is expressed in terms of curvatures and related to conformal
higher-spin gravity. The generalized higher-spin Weyl anomalies are also
determined. The relation with the theory of interacting higher-spin gauge
fields on anti de Sitter spacetime via the holographic correspondence is
discussed.Comment: 40 pages, Some errors and typos corrected, Version published in JHE
Zero Mach Number Limit of the Compressible Primitive Equations: Well-Prepared Initial Data
Funder: Einstein Stiftung Berlin; doi: http://dx.doi.org/10.13039/501100006188Funder: John Simon Guggenheim Memorial Foundation; doi: http://dx.doi.org/10.13039/100005851This work concerns the zero Mach number limit of the compressible primitive
equations. The primitive equations with the incompressibility condition are
identified as the limiting equations. The convergence with well-prepared
initial data (i.e., initial data without acoustic oscillations) is rigorously
justified, and the convergence rate is shown to be of order , as , where
represents the Mach number. As a byproduct, we construct a class of global
solutions to the compressible primitive equations, which are close to the
incompressible flows
Multi-valued, singular stochastic evolution inclusions
We provide an abstract variational existence and uniqueness result for
multi-valued, monotone, non-coercive stochastic evolution inclusions in Hilbert
spaces with general additive and Wiener multiplicative noise. As examples we
discuss certain singular diffusion equations such as the stochastic 1-Laplacian
evolution (total variation flow) in all space dimensions and the stochastic
singular fast diffusion equation. In case of additive Wiener noise we prove the
existence of a unique weak-* mean ergodic invariant measure.Comment: 39 pages, in press: J. Math. Pures Appl. (2013
Charmonium Absorption in the Meson-exchange Model
We review the meson-exchange model for charmonium absorption by hadrons. This
includes the construction of the interaction Lagrangians, the determination of
the coupling constants, the introduction of form factors, and the predicted
cross sections for absorption by both mesons and nucleons. We further
discuss the effects due to anomalous parity interactions, uncertainties in form
factors, constraints from chiral symmetry, and the change of charmed meson mass
in medium on the cross sections for charmonium absorption in hadronic matter.Comment: 10 pages, 2 figures. Talk given at Quark Matter 2002 (QM 2002),
Nantes, France, 18-24 July 2002. To appear in the proceedings (Nucl. Phys. A
Leaf growth in early development is key to biomass heterosis in Arabidopsis.
Arabidopsis thaliana hybrids have similar properties to hybrid crops with greater biomass relative to the parents. We asked whether the greater biomass was due to increased photosynthetic efficiency per unit leaf area or to overall increased leaf area and increased total photosynthate per plant. We found that photosynthetic parameters (electron transport rate, CO2 assimilation rate, chlorophyll content, chloroplast number) were unchanged on a leaf unit area and unit fresh weight basis between parents and hybrids indicating that heterosis is not a result of increased photosynthetic efficiency. To investigate the possibility of increased leaf area producing more photosynthate per plant we studied C24/ Landsberg erecta (Ler) hybrids in detail. These hybrids have earlier germination and leaf growth than the parents leading to a larger leaf area at any point in development of the plant. The developing leaves of the hybrids are significantly larger than those of the parents with consequent greater production of photosynthate and an increased contribution to heterosis. The set of leaves contributing to heterosis changes as the plant develops; the four most recently emerged leaves make the greatest contribution. As a leaf matures, its contribution to heterosis attenuates. While photosynthesis per unit leaf area is unchanged at any stage of development in the hybrid, leaf area is greater and the amount of photosynthate per plant is increased
Use of functional MRI to evaluate correlation between acupoints and the somatic sensory cortex activities
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