847 research outputs found
Vitronectin Increases Vascular Permeability by Promoting VE-Cadherin Internalization at Cell Junctions
Cross-talk between integrins and cadherins regulates cell function. We tested the hypothesis that vitronectin (VN), a multi-functional adhesion molecule present in the extracellular matrix and plasma, regulates vascular permeability via effects on VE-cadherin, a critical regulator of endothelial cell (EC) adhesion.Addition of multimeric VN (mult VN) significantly increased VE-cadherin internalization in human umbilical vein EC (HUVEC) monolayers. This effect was blocked by the anti-α(V)β(3) antibody, pharmacological inhibition and knockdown of Src kinase. In contrast to mult VN, monomeric VN did not trigger VE-cadherin internalization. In a modified Miles assay, VN deficiency impaired vascular endothelial growth factor-induced permeability. Furthermore, ischemia-induced enhancement of vascular permeability, expressed as the ratio of FITC-dextran leakage from the circulation into the ischemic and non-ischemic hindlimb muscle, was significantly greater in the WT mice than in the Vn(-/-) mice. Similarly, ischemia-mediated macrophage infiltration was significantly reduced in the Vn(-/-) mice vs. the WT controls. We evaluated changes in the multimerization of VN in ischemic tissue in a mouse hindlimb ischemia model. VN plays a previously unrecognized role in regulating endothelial permeability via conformational- and integrin-dependent effects on VE-cadherin trafficking.These results have important implications for the regulation of endothelial function and angiogenesis by VN under normal and pathological conditions
Reduced conditioned fear response in mice that lack Dlx1 and show subtype-specific loss of interneurons
The inhibitory GABAergic system has been implicated in multiple neuropsychiatric diseases such as schizophrenia and autism. The Dlx homeobox transcription factor family is essential for development and function of GABAergic interneurons. Mice lacking the Dlx1 gene have postnatal subtype-specific loss of interneurons and reduced IPSCs in their cortex and hippocampus. To ascertain consequences of these changes in the GABAergic system, we performed a battery of behavioral assays on the Dlx1 mutant mice, including zero maze, open field, locomotor activity, food intake, rotarod, tail suspension, fear conditioning assays (context and trace), prepulse inhibition, and working memory related tasks (spontaneous alteration task and spatial working memory task). Dlx1 mutant mice displayed elevated activity levels in open field, locomotor activity, and tail suspension tests. These mice also showed deficits in contextual and trace fear conditioning, and possibly in prepulse inhibition. Their learning deficits were not global, as the mutant mice did not differ from the wild-type controls in tests of working memory. Our findings demonstrate a critical role for the Dlx1 gene, and likely the subclasses of interneurons that are affected by the lack of this gene, in behavioral inhibition and associative fear learning. These observations support the involvement of particular components of the GABAergic system in specific behavioral phenotypes related to complex neuropsychiatric diseases
Study of the doubly Cabibbo-suppressed decays and
Based on 7.33 fb of collision data collected at
center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector,
the experimental studies of the doubly Cabibbo-suppressed decays and are reported. We determine the
absolute branching fraction of to be
() . No
significant signal of is observed and the upper
limit on its decay branching fraction at 90\% confidence level is set to be
.Comment: 10 pages, 4 figures, 4 table
A New Look at the Scalar Meson via Decays
Using of collision data collected with the
BESIII detector at the center-of-mass energy of 3.773 GeV, we investigate the
semileptonic decays ( and ).
The decay is observed for the first time. By
analyzing simultaneously the differential decay rates of and in different
four-momentum transfer intervals, the product of the relevant hadronic form
factor and the magnitude of the
Cabibbo-Kobayashi-Maskawa matrix element is determined to be
for
the first time. With the input of from the global fit in the
standard model, we determine . The absolute branching fractions of and are determined as and . Combining these results with those of previous BESIII measurements on
their semielectronic counterparts from the same data sample, we test lepton
flavor universality by measuring the branching fraction ratios and , which are
compatible with the standard model expectation.Comment: Supplemental Materials added in this versio
Partial Wave Analysis of
Using a sample of events collected with
the BESIII detector at the BEPCII collider, a partial wave analysis on the
decay is performed to investigate the intermediate
resonances in . The
resonances , , , ,
, , , , and
are observed with statistical significance greater than 5.
The product branching fractions are reported. The resonance parameters of
and are also measured
Updated measurements of the M1 transition with
Based on a data sample of events
collected with the BESIII detector at the BEPCII collider, the M1 transition
with is
studied, where is or
. The mass and width of the are
measured to be MeV/
and MeV, respectively. The
product branching fraction is determined to be . Using , we obtain the branching fraction of the
radiative transition to be , where the third uncertainty is due to the quoted
First measurements of the absolute branching fraction of and upper limit on
The absolute branching fraction of the decay is measured for the first time to be with 368.48 pb of
collision data collected by the BESIII detector at the center-of-mass energies
of and GeV. This result is lower than the naive
prediction of 67\%, obtained from isospin symmetry, by more than ,
thereby indicating that the novel mechanism referred to as the
\textit{threshold effect}, proposed for the strong decays of
, also applies to . This
measurement is necessary to obtain the coupling constants for the transitions
between -wave and -wave charmed baryons in heavy hadron chiral
perturbation theory. In addition, we search for the decay
. No significant signal is
observed, and the upper limit on its branching fraction is determined to be
80.8\% at the 90\% confidence level.Comment: 8 pages, 6 figure
Observation of the and evidence for a new vector charmonium-like state in
Cross sections for the process
at center-of-mass energies from to GeV are measured using data
samples with a total integrated luminosity of 21.2 fb collected by the
BESIII detector operating at the BEPCII storage ring. The state is
observed in the energy dependence of the cross section for the first time with a statistical significance of
26.0. In addition, an enhancement around GeV, called the
, is seen with a statistical significance of 4.2. There is no
clear structure around GeV. Using a fit with a coherent sum of three
Breit-Wigner functions, we determine the mass and width of the state
to be MeV/ and MeV,
respectively, and the mass and width of the state to be MeV/ and MeV, respectively,
where the first uncertainties are statistical and the second are systematic. In
addition, the average Born cross section ratio of to is measured to be
, or if
three-body phase space is considered.Comment: Update draft based the comments from PRD refere
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