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Genes and Pathways Regulating Decline in Lung Function and Airway Remodeling in Asthma.
Asthma is a common disorder of the airways characterized by airway inflammation and by decline in lung function and airway remodeling in a subset of asthmatics. Airway remodeling is characterized by structural changes which include airway smooth muscle hypertrophy/hyperplasia, subepithelial fibrosis due to thickening of the reticular basement membrane, mucus metaplasia of the epithelium, and angiogenesis. Epidemiologic studies suggest that both genetic and environmental factors may contribute to decline in lung function and airway remodeling in a subset of asthmatics. Environmental factors include respiratory viral infection-triggered asthma exacerbations, and tobacco smoke. There is also evidence that several asthma candidate genes may contribute to decline in lung function, including ADAM33, PLAUR, VEGF, IL13, CHI3L1, TSLP, GSDMB, TGFB1, POSTN, ESR1 and ARG2. In addition, mediators or cytokines, including cysteinyl leukotrienes, matrix metallopeptidase-9, interleukin-33 and eosinophil expression of transforming growth factor-β, may contribute to airway remodeling in asthma. Although increased airway smooth muscle is associated with reduced lung function (i.e. forced expiratory volume in 1 second) in asthma, there have been few long-term studies to determine how individual pathologic features of airway remodeling contribute to decline in lung function in asthma. Clinical studies with inhibitors of individual gene products, cytokines or mediators are needed in asthmatic patients to identify their individual role in decline in lung function and/or airway remodeling
Quantum phase transition in HTSC thick films: YBa2Cu 3O x, YBa2Cu3O x (5 % Ag-Doped) in a Strong Pulsed Magnetic Field up to 32 T at low temperatures (58-100 K), current densities and stress-effect
We have researched the influence of pulsed magnetic fields up to 32 T on the magneto-resistance of thick films (50 Mk) of YBa2Cu3O x and YBa2Cu3O x (5 % Ag-doped) that were produced from synthesized powders. (Figs. 1-9): concentrate with 6.85-6.9 % O2 and a tail fraction 6.5-6.6 % O2. We observed a linear plot at currents of more than 1 mA at 77 K in YBa2Cu 3O x (5 % Ag-doped) at B>5 T and in the concentrate YBa2Cu3O x samples with I=1 mA, T=68.2 K. Pulsed magnetic fields up to 32 T, at I=1 mA had practically no influence on the value of the magneto-resistance in the concentrate YBa2Cu 3O x specimens at T=57.9 K and up to 17 T for YBa 2Cu3O x (5 % Ag) at 77 K (Meissner effect). However, for B>17 T, YBa2Cu3O x (5 % Ag) at 77 K demonstrates a tendency toward lower resistance. In the presence to 10 pulses in a cyclic pulsed magnetic field of 32 T, there is a sharp change of magnetic properties of an HTSC that can lead to nontrivial changes in the transition temperature, due to the strong mechanic stresses, sharp change value structure, and because one of the phases becomes superconducting (Figs. 3A, 3B). The behavior of the magnetoresistance of S-N-S contacts in pulsed magnetic fields is described via the system's parallel resistance, R n, and the inductance, L S-N-S. Analysis of microscopic models of quantum phase transitions was made in a granular superconductor in an attempt to explain the results on the studied HTSC-films and to give a physical interpretation to the deduced parameters of some experiments on the basis of "spin (vortex) glass" (vortex ice). © 2012 Springer Science+Business Media New York
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Distribution of α7 Nicotinic Acetylcholine Receptor Subunit mRNA in the Developing Mouse.
Homomeric α7 nicotinic acetylcholine receptors (nAChRs) are abundantly expressed in the central and peripheral nervous system (CNS and PNS, respectively), and spinal cord. In addition, expression and functional responses have been reported in non-neuronal tissue. In the nervous system, α7 nAChR subunit expression appears early during embryonic development and is often transiently upregulated, but little is known about their prenatal expression outside of the nervous system. For understanding potential short-term and long-term effects of gestational nicotine exposure, it is important to know the temporal and spatial expression of α7 nAChRs throughout the body. To that end, we studied the expression of α7 nAChR subunit mRNA using highly sensitive isotopic in situ hybridization in embryonic and neonatal whole-body mouse sections starting at gestational day 13. The results revealed expression of α7 mRNA as early as embryonic day 13 in the PNS, including dorsal root ganglia, parasympathetic and sympathetic ganglia, with the strongest expression in the superior cervical ganglion, and low to moderate levels were detected in brain and spinal cord, respectively, which rapidly increased in intensity with embryonic age. In addition, robust α7 mRNA expression was detected in the adrenal medulla, and low to moderate expression in selected peripheral tissues during embryonic development, potentially related to cells derived from the neural crest. Little or no mRNA expression was detected in thymus or spleen, sites of immune cell maturation. The results suggest that prenatal nicotine exposure could potentially affect the nervous system with limited effects in non-neural tissues
Leer entre… La formación de jóvenes mediadores culturales como política de lectura
A partir del análisis de dos experiencias de formación de jóvenes mediadores culturales comunitarios realizadas en Pacheco, Buenos Aires, y Las Heras, Santa Cruz, se desarrollan tres conceptos en torno a las políticas de lectura: el gesto, la trama y la representación
Heterogeneous nucleation near a metastable vapour-liquid transition: the effect of wetting transitions
Phase transformations such as freezing typically start with heterogeneous
nucleation. Heterogeneous nucleation near a wetting transition, of a
crystalline phase is studied. The wetting transition occurs at or near a
vapour-liquid transition which occurs in a metastable fluid. The fluid is
metastable with respect to crystallisation, and it is the crystallisation of
this fluid phase that we are interested in. At a wetting transition a thick
layer of a liquid phase forms at a surface in contact with the vapour phase.
The crystalline nucleus is then immersed in this liquid layer, which reduces
the free energy barrier to nucleation and so dramatically increases the
nucleation rate. The variation in the rate of heterogeneous nucleation close to
wetting transitions is calculated for systems in which the longest-range forces
are dispersion forces.Comment: 11 pages including 3 figure
Cholinergic cells in the nucleus basalis of mice express the N-methyl-D-aspartate-receptor subunit NR2C and its replacement by the NR2B subunit enhances frontal and amygdaloid acetylcholine levels
It is known that glutamatergic and cholinergic systems interact functionally at the level of the cholinergic basal forebrain. The N-methyl-D-aspartate receptor (NMDA-R) is a multiprotein complex composed of NR1, NR2 and/or NR3 subunits. The subunit composition of NMDA-R of cholinergic cells in the nucleus basalis has not yet been investigated. Here, by means of choline acetyl transferase and NR2B or NR2C double staining, we demonstrate that mice express both the NR2C and NR2B subunits in nucleus basalis cholinergic cells.We generated NR2C-2B mutant mice in which an insertion of NR2B cDNA into the gene locus of the NR2C gene replaced NR2C by NR2B expression throughout the brain. This NR2C-2B mutant was used to examine whether a subunit exchange in cholinergic neurons would affect acetylcholine (ACh) content in several brain structures. We found increased ACh levels in the frontal cortex and amygdala in the brains of NR2C-2B mutant mice. Brain ACh has been implicated in neuroplasticity, novelty-induced arousal and encoding of novel stimuli. We therefore assessed behavioral habituation to novel environments and objects as well as object recognition in NR2C-2B subunit exchange mice. The behavioral analysis did not indicate any gross behavioral alteration in the mutant mice compared with the wildtype mice. Our results show that the NR2C by NR2B subunit exchange in mice affects ACh content in two target areas of the nucleus basalis.
A Subgroup of First-Degree Relatives of Crohn's Disease Patients Shows a Profile of Inflammatory Markers in the Blood Which Is More Typical of Crohn's Disease Patients Than of Normal Individuals
Introduction. Family member with IBD is the greatest risk factor for developing the disease. The hematological profile of first-degree relatives (FDRs) of Crohn's disease (CD) patients was studied in order to identify healthy FDRs at risk to develop disease. Materials and methods. Thirty CD patients, 90 FDRs, and 28 non-related individuals (controls) were enrolled. Hematological profile and C-reactive protein were determined. Results. All hematological parameters were significantly different in CD patients compared to controls, with significantly higher levels of CRP, WBC, PMN, MONO, and PLT and lower Hb and lymphocyte count. The hematological profile of FDRs showed values between the controls and CD patients with ten FDRs that their parameters matched those of CD patients and significantly different from other FDRs. This group was defined as high-risk relatives (HRRs). Conclusions. Analysis of the hematological profile and CRP level might be proven as a fast, reliable, and less money-consuming tool to identify FDRs with a probable increased risk to develop the disease
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