3,903 research outputs found
Maternal Baicalin Treatment Increases Fetal Lung Surfactant Phospholipids in Rats
Baicalin is a flavonoid compound purified from the medicinal plant Scutellaria baicalensis Georgi and has been reported to stimulate surfactant protein (SP)-A gene expression in human lung epithelial cell lines (H441). The aims of this study were to determine whether maternal baicalin treatment could increase lung surfactant production and induce lung maturation in fetal rats. This study was performed with timed pregnant Sprague-Dawley rats. One-day baicalin group mothers were injected intraperitoneally with baicalin (5 mg/kg/day) on Day 18 of gestation. Two-day baicalin group mothers were injected intraperitoneally with baicalin (5 mg/kg/day) on Days 17 and 18 of gestation. Control group mothers were injected with vehicle alone on Day 18 of gestation. On Day 19 of gestation, fetuses were delivered by cesarean section. Maternal treatment with 2-day baicalin significantly increased saturated phospholipid when compared with control group and total phospholipid in fetal lung tissue when compared with control and 1-day baicalin groups. Antenatal treatment with 2-day baicalin significantly increased maternal growth hormone when compared with control group. Fetal lung SP-A mRNA expression and maternal serum corticosterone levels were comparable among the three experimental groups. Maternal baicalin treatment increases pulmonary surfactant phospholipids of fetal rat lungs and the improvement was associated with increased maternal serum growth hormone. These results suggest that antenatal baicalin treatment might accelerate fetal rat lung maturation
Portal Vein Gas in a Diabetic Patient with Gas-forming Pararenal Abscess
The incidence of portal vein gas (PVG), which used to be an ominous sign of intestinal sepsis, has increased with progressive improvements in imaging modalities. Therefore, the clinical significance of PVG has changed. Emphysematous pyelonephritis (EPN) is a rare, potentially life-threatening and gas-forming infection of the renal parenchyma and/or its surroundings. Gas-forming pararenal abscess presenting with PVG is even rarer. We hereby present the case of a diabetic female with poor glycemic control, who was diagnosed to have EPN and PVG concurrently by computed tomography. She underwent percutaneous catheter drainage (PCD) of the pyelonephritis. Both cultures of blood and pus grew Klebsiella pneumoniae. Her subsequent clinical course was uneventful. In summary, EPN is a rare but potentially fatal urinary tract infection in diabetic patients, and finding PVG on computed tomography can aid in diagnosis. Conservative treatment with intravenous antibiotics and PCD of pus may be adequate for the patient with EPN. However, nephrectomy may be necessary if the patient deteriorates and PCD fails to contain the infection
3D Magneto-Hydrodynamic Simulations of Parker Instability with Cosmic Rays
This study investigates Parker instability in an interstellar medium (ISM)
near the Galactic plane using three-dimensional magneto-hydrodynamic
simulations. Parker instability arises from the presence of a magnetic field in
a plasma, wherein the magnetic buoyant pressure expels the gas and cause the
gas to move along the field lines. The process is thought to induce the
formation of giant molecular clouds in the Galaxy. In this study, the effects
of cosmic-ray (CR) diffusion are examined. The ISM at equilibrium is assumed to
comprise a plasma fluid and a CR fluid at various temperatures, with a uniform
magnetic field passing through it in the azimuthal direction of the Galactic
disk. After a small perturbation, the unstable gas aggregates at the footpoint
of the magnetic fields and forms dense blobs. The growth rate of the
instability increases with the strength of the CR diffusion. The formation of
dense clouds is enhanced by the effect of cosmic rays (CRs), whereas the shape
of the clouds depends sensitively on the initial conditions of perturbation.Comment: 4 pages, Computer Physics Communications 2011, 182, p177-17
Decoration of graphene nanoribbons by transition-metal elements
Graphene is a famous truly two-dimensional (2D) material, possessing a
cone-like energy structure near the Fermi level and treated as a gapless
semiconductor. Its unique properties trigger researchers to find applications
of it. The gapless feature shrinks the development of graphene nanoelectronics.
Making one-dimensional (1D) strips of graphene nanoribbons (GNRs) could be one
of the promising routes to modulating the electronic and optical properties of
graphene. The electronic and optical properties of GNRs are highly sensitive to
the edge and width. The tunability in electronic and optical properties further
implies the possibilities of GNR application. However, the dangling bonds at
ribbon edges remain an open question in GNR systems. Various passivation at the
ribbon edge might change the essential physical properties. In this work,
transition-metal elements are considered as the guest atoms at the edges. The
geometric structure, energy bands, density of states, charge distribution, and
optical transitions are discussed
Disordered Fe vacancies and superconductivity in potassium-intercalated iron selenide (K2-xFe4+ySe5)
The parent compound of an unconventional superconductor must contain unusual
correlated electronic and magnetic properties of its own. In the high-Tc
potassium intercalated FeSe, there has been significant debate regarding what
the exact parent compound is. Our studies unambiguously show that the
Fe-vacancy ordered K2Fe4Se5 is the magnetic, Mott insulating parent compound of
the superconducting state. Non-superconducting K2Fe4Se5 becomes a
superconductor after high temperature annealing, and the overall picture
indicates that superconductivity in K2-xFe4+ySe5 originates from the Fe-vacancy
order to disorder transition. Thus, the long pending question whether magnetic
and superconducting state are competing or cooperating for cuprate
superconductors may also apply to the Fe-chalcogenide superconductors. It is
believed that the iron selenides and related compounds will provide essential
information to understand the origin of superconductivity in the iron-based
superconductors, and possibly to the superconducting cuprates
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