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Hypoxia-inducible factor: role in cell survival in superoxide dismutase overexpressing mice after neonatal hypoxia-ischemia.
BackgroundSixty percent of infants with severe neonatal hypoxic-ischemic encephalopathy die, while most survivors have permanent disabilities. Treatment for neonatal hypoxic-ischemic encephalopathy is limited to therapeutic hypothermia, but it does not offer complete protection. Here, we investigated whether hypoxia-inducible factor (HIF) promotes cell survival and suggested neuroprotective strategies.PurposeHIF-1α-deficient mice have increased brain injury after neonatal hypoxia-ischemia (HI), and the role of HIF-2α in HI is not well characterized. Copper-zinc superoxide dismutase (SOD)1 overexpression is not beneficial in neonatal HI. The expression of HIF-1α and HIF-2α was measured in SOD1 overexpressing mice and compared to wild-type littermates to see if alteration in expression explains this lack of benefit.MethodsOn postnatal day 9, C57Bl/6 mice were subjected to HI, and protein expression was measured by western blotting in the ipsilateral cortex of wild-type and SOD1 overexpressing mice to quantify HIF-1α and HIF-2α. Spectrin expression was also measured to characterize the mechanism of cell death.ResultsHIF-1α protein expression did not significantly change after HI injury in the SOD1-overexpressing or wild-type mouse cortex. However, HIF-2α protein expression increased 30 minutes after HI injury in the wild-type and SOD1-overexpressing mouse cortex and decreased to baseline value at 24 hours after HI injury. Spectrin 145/150 expression did not significantly change after HI injury in the SOD1- overexpressing or wild-type mouse cortex. However, spectrin 120 expression increased in both wild-type and SOD1-overexpressing mouse at 4 hours after HI, which decreased by 24 hours, indicating a greater role of apoptotic cell death.ConclusionHIF-1α and HIF-2α may promote cell survival in neonatal HI in a cell-specific and regional fashion. Our findings suggest that early HIF-2α upregulation precedes apoptotic cell death and limits necrotic cell death. However, the influence of SOD was not clarified; it remains an intriguing factor in neonatal HI
Possible f-wave superconductivity in SrRuO?
Until recently it has been believed that the superconductivity in
SrRuO is described by p-wave pairing. However, both the recent specific
heat and the magnetic penetration depth measurements on the purest single
crystals of SrRuO appear to be explained more consistently in terms of
f-wave superconductivity. In order to further this hypothesis, we study
theoretically the thermodynamics and thermal conductivity of f-wave
superconductors in a planar magnetic field. We find the simple expressions for
these quantities when and , which should be
readily accessible experimentally.Comment: 6 pages, 2 figure
ECONOMIC FEASIBILITY OF THE CATTLE FEEDING INDUSTRY IN THE NORTHERN PLAINS AND WESTERN LAKES STATES - SUMMARY
The five-state study area of the Northern Plains and Western Lakes States, Minnesota, Montana, North Dakota, South Dakota, and Wisconsin, has adequate feed supplies and feeder cattle to markedly increase cattle feeding. Feed costs in these states have historically been lower than in the Southern Plains States. However, higher transportation costs appear to offset that advantage. Close access to slaughter plants in these states could offset that transportation disadvantage. Backgrounding of cattle appears to be quite profitable and cattle feeding, especially in larger sized feedlots, can be profitable. However, the cattle feeding industry has an increasing level of excess capacity. To be successful, new feedlots in the Northern Plains and Western Lakes States would need cost efficiencies to offset higher production costs, compared to Nebraska and Kansas, or would need to produce for a niche market unaffected by the lower operating costs of already established feedlots in the Central and Southern Plains States. Finally, a range of strategies are available in developing value-added cattle production in the Northern Plains and Western Lakes States. These strategies embody differing levels of capital investment, and involve different levels of risk and profitability.cattle feeding, Northern Plains, economies of scale, cooperative ownership, entrance strategies, Production Economics,
Quantum State Discrimination with General Figures of Merit
We solve the problem of quantum state discrimination with "general
(symmetric) figures of merit" for an even number of symmetric quantum bits with
use of the no-signaling principle. It turns out that conditional probability
has the same form for any figure of merit. Optimal measurement and
corresponding conditional probability are the same for any monotonous figure of
merit.Comment: 5 pages, 2 figure
Novel vortex lattice transition in d-wave superconductors
We study the vortex state in a magnetic field parallel to the axis in the
framework of the extended Ginzburg Landau equation. We find the vortex acquires
a fourfold modulation proportional to where is the angle
makes with the -axis. This term gives rise to an attractive
interaction between two vortices when they are aligned parallel to or
. We predict the first order vortex lattice transition at
from triangular into the square lattice
tilted by from the axis. This gives the critical field
a few Tesla for YBCO and Bi2212 monocrystals at low temperatures ().Comment: 6 pages, 4 figure
Thermal conductivity in B- and C- phase of UPt_3
Although the superconductivity in UPt_3 is one of the most well studied,
there are still lingering questions about the nodal directions in the B and C
phase in the presence of a magnetic field. Limiting ourselves to the low
temperature regime (T<<Delta(0)), we study the magnetothermal conductivity with
in semiclassical approximation using Volovik's approach. The angular dependence
of the magnetothermal conductivity for an arbitrary field direction should
clarify the nodal structure in UPt_3.Comment: 4 pages, 5 figure
Threshold electric field in unconventional density waves
As it is well known most of charge density wave (CDW) and spin density wave
(SDW) exhibit the nonlinear transport with well defined threshold electric
field E_T. Here we study theoretically the threshold electric field of
unconventional density waves. We find that the threshold field increases
monotonically with temperature without divergent behaviour at T_c, unlike the
one in conventional CDW. The present result in the 3D weak pinning limit
appears to describe rather well the threshold electric field observed recently
in the low-temperature phase (LTP) of alpha-(BEDT-TTF)_2KHg(SCN)_4.Comment: 4 pages, 2 figure
Identification of presumed pathogenic KRT3 and KRT12 gene mutations associated with Meesmann corneal dystrophy.
PurposeTo report potentially pathogenic mutations in the keratin 3 (KRT3) and keratin 12 (KRT12) genes in two individuals with clinically diagnosed Meesmann corneal dystrophy (MECD).MethodsSlit-lamp examination was performed on the probands and available family members to identify characteristic features of MECD. After informed consent was obtained, saliva samples were obtained as a source of genomic DNA, and screening of KRT3 and KRT12 was performed. Potentially pathogenic variants were screened for in 200 control chromosomes. PolyPhen-2, SIFT, and PANTHER were used to predict the functional impact of identified variants. Short tandem repeat genotyping was performed to confirm paternity.ResultsSlit-lamp examination of the first proband demonstrated bilateral, diffusely distributed, clear epithelial microcysts, consistent with MECD. Screening of KRT3 revealed a heterozygous missense variant in exon 1, c.250C>T (p.(Arg84Trp)), which has a minor allele frequency of 0.0076 and was not identified in 200 control chromosomes. In silico analysis with PolyPhen-2 and PANTHER predicted the variant to be damaging to protein function; however, SIFT analysis predicted tolerance of the variant. The second proband demonstrated bilateral, diffusely distributed epithelial opacities that appeared gray-white on direct illumination and translucent on retroillumination. Neither parent demonstrated corneal opacities. Screening of KRT12 revealed a novel heterozygous insertion/deletion variant in exon 6, c.1288_1293delinsAGCCCT (p.(Arg430_Arg431delinsSerPro)). This variant was not present in either of the proband's parents or in 200 control chromosomes and was predicted to be damaging by PolyPhen-2, PANTHER, and SIFT. Haplotype analysis confirmed paternity of the second proband, indicating that the variant arose de novo.ConclusionsWe present a novel KRT12 mutation, representing the first de novo mutation and the first indel in KRT12 associated with MECD. In addition, we report a variant of uncertain significance in KRT3 in an individual with MECD. Although the potential pathogenicity of this variant is unknown, it is the first variant affecting the head domain of K3 to be reported in an individual with MECD and suggests that disease-causing variants associated with MECD may not be restricted to primary sequence alterations of either the helix-initiation or helix-termination motifs of K3 and K12
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