Threshold J/ψ−J/\psi- production in nucleon-nucleon collisions

We analyze $J/\psi-$ production in nucleon-nucleon collisions near threshold in the framework of a general model independent formalism, which can be applied to any reaction $N+N\to N+N+V^0$, where $V^0=\omega$, $\phi$, or $J/\psi$. Such reactions show large isotopic effects: a large difference for $pp$- and $pn$-collisions, which is due to the different spin structure of the corresponding matrix elements. The analysis of the spin structure and of the polarization observables is based on symmetry properties of the strong interaction. Using existing experimental data on the different decays of $J/\psi-$meson, we suggest a model for $N+N\to N+N+J/\psi$, based on $t-$channel $\eta+\pi$-exchanges. We predict polarization phenomena for the $n+p\to n+p+J/\psi$-reaction and the ratio of cross sections for $np$ and $pp$-collisions. For the processes $\eta(\pi)+N\to N+J/\psi$ we apply two different approaches: vector meson exchange and local four-particle interaction. In both cases we find larger $J/\psi$-production in $np$-collisions, with respect to $pp$-collisions.Comment: 17 pages, 6 figure

Diagnosis and treatment of asymptomatic left ventricular systolic dysfunction after myocardial infarction.

The increased survival after acute myocardial infarction induced an increase in heart failure with left ventricular systolic dysfunction. Early detection and treatment of asymptomatic left ventricular systolic dysfunction give the chance to improve outcomes and to reduce costs due to the management of patients with overt heart failure

Hydrogen migration at restructuring palladium-silver oxide boundaries dramatically enhances reduction rate of silver oxide.

Heterogeneous catalysts are complex materials with multiple interfaces. A critical proposition in exploiting bifunctionality in alloy catalysts is to achieve surface migration across interfaces separating functionally dissimilar regions. Herein, we demonstrate the enhancement of more than 104 in the rate of molecular hydrogen reduction of a silver surface oxide in the presence of palladium oxide compared to pure silver oxide resulting from the transfer of atomic hydrogen from palladium oxide islands onto the surrounding surface formed from oxidation of a palladium-silver alloy. The palladium-silver interface also dynamically restructures during reduction, resulting in silver-palladium intermixing. This study clearly demonstrates the migration of reaction intermediates and catalyst material across surface interfacial boundaries in alloys with a significant effect on surface reactivity, having broad implications for the catalytic function of bimetallic materials

CXCL12/SDF-1 from perisynaptic Schwann cells promotes regeneration of injured motor axonterminals

The neuromuscular junction has retained through evolution the capacity to regenerate after damage, but little is known on the inter-cellular signals involved in its functional recovery from trauma, autoimmune attacks, or neurotoxins. We report here that CXCL12, also abbreviated as stromal-derived factor-1 (SDF-1), is produced specifically by perisynaptic Schwann cells following motor axon terminal degeneration induced by -latrotoxin. CXCL12 acts via binding to the neuronal CXCR4 receptor. A CXCL12-neutralizing antibody or a specific CXCR4 inhibitor strongly delays recovery from motor neuron degeneration invivo. Recombinant CXCL12 invivo accelerates neurotransmission rescue upon damage and very effectively stimulates the axon growth of spinal cord motor neurons invitro. These findings indicate that the CXCL12-CXCR4 axis plays an important role in the regeneration of the neuromuscular junction after motor axon injury. The present results have important implications in the effort to find therapeutics and protocols to improve recovery of function after different forms of motor axon terminal damage

P-parity of charmed particles from associative photoproduction of D and D^*-mesons

We suggest to measure the triple polarization correlations in the exclusive associative charm particle photoproduction, vector gamma + vector p --> vector Lambda_c^{++} bar{D^0} with linearly polarized photons, as a method to determine the P-parity of the charmed D-meson. The dependence of these correlations on the parity P(N Lambda_c D) can be predicted in model independent way. The t-dependence of the differential cross section for vector meson photoproduction, gamma + p --> Lambda_c^{++} bar{D^{*0}}, in a model based on D-exchange, is also sensitive to P(N Lambda_c D).Comment: 11 pages, 1 figur

Variability and synchronism of leaf appearance and leaf elongation rates of eleven contrasting rice genotypes

Leaf appearance and leaf elongation rates in rice play an essential role in determining the development of the plants' architecture which affects their adaptability to varying environments. This study aimed to characterize the rates of leaf appearance and elongation on all leaves of the main culms of rice plants for 11 contrasting varieties and to determine if the decrease in the leaf appearance rate was related to a simultaneous decrease in the rate of leaf elongation. Forty four 13-L pots were sown with one plant from one genotype and laid out in 4 randomized complete blocks. The experiment, conducted inside a greenhouse, was repeated twice. The increase in length of the leaves expanding on the main stems was monitored daily until flag leaf. Data were used to estimate the rates of leaf appearance and leaf elongation. Significant variability in the rate of leaf appearance, rate of leaf elongation, and leaf length was found across varieties. The kinetics of leaf appearance had linear phases intermediated by a curvilinear phase, without sharp changes in the phyllochron duration. Maximal leaf elongation rate (LER) of all genotypes (except for one) increased linearly with leaf rank until it reached its maximum value at leaf 8 to 10 (11 - 12 for Azucena) where it stabilized before decreasing linearly with leaf rank for the last leaves. Finally, both rates of leaf appearance and leaf elongation evolved with time more smoothly than expected so no sharp decrease in LER occurred at the time of the decrease in leaf appearance rate of the last leaves. However, the trilinear model fits the data well enough to remain useful in efficiently comparing the leaf appearance kinetics of contrasting varieties. (Résumé d'auteur

Overexpression of Mcl-1 exacerbates lymphocyte accumulation and autoimmune kidney disease in lpr mice

Cell death by apoptosis has a critical role during embryonic development and in maintaining tissue homeostasis. In mammals, there are two converging apoptosis pathways: the ‘extrinsic’ pathway, which is triggered by engagement of cell surface ‘death receptors’ such as Fas/APO-1; and the ‘intrinsic’ pathway, which is triggered by diverse cellular stresses, and is regulated by prosurvival and pro-apoptotic members of the Bcl-2 family of proteins. Pro-survival Mcl-1, which can block activation of the proapoptotic proteins, Bax and Bak, appears critical for the survival and maintenance of multiple haemopoietic cell types. To investigate the impact on haemopoiesis of simultaneously inhibiting both apoptosis pathways, we introduced the vavP-Mcl-1 transgene, which causes overexpression of Mcl-1 protein in all haemopoietic lineages, into Faslpr/lpr mice, which lack functional Fas and are prone to autoimmunity. The combined mutations had a modest impact on myelopoiesis, primarily an increase in the macrophage/monocyte population in Mcl-1tg/lpr mice compared with lpr or Mcl-1tg mice. The impact on lymphopoiesis was striking, with a marked elevation in all major lymphoid subsets, including the non-conventional double-negative (DN) T cells (TCRβ+ CD4– CD8– B220+ ) characteristic of Faslpr/lpr mice. Of note, the onset of autoimmunity was markedly accelerated in Mcl-1tg/lpr mice compared with lpr mice, and this was preceded by an increase in immunoglobulin (Ig)-producing cells and circulating autoantibodies. This degree of impact was surprising, given the relatively mild phenotype conferred by the vavP-Mcl-1 transgene by itself: a two- to threefold elevation of peripheral B and T cells, no significant increase in the non-conventional DN T-cell population and no autoimmune disease. Comparison of the phenotype with that of other susceptible mice suggests that the development of autoimmune disease in Mcl-1tg/lpr mice may be influenced not only by Ig-producing cells but also other haemopoietic cell types

Comparación de frecuencias alélicas y genotípicas de los polimorfismos CAPN1-316 Y CAPN1-4751 del gen de la Calpaina en tres poblaciones de ganado criollo boliviano

La terneza de la carne está en parte determinada por el sistema proteico calpaína (CAPN1) / calpastatina (CAST). Bolivia posee en los llanos tres biotipos de ganado Criollo: los Yacumeños, los Chaqueños y los Saavedreños. El objetivo del presente trabajo fue determinar la frecuencia alélica y genotípica del gen de la CAPN1 en tres poblaciones de ganado Criollo de Bolivia. Se obtuvieron muestras de sangre de 28 Criollos del Chaco (CCH), 85 Criollos Yacumeños (CYA) y 30 Criollos Saavedreños (CSV). El ADN se extrajo utilizando el kit comercial Wizard® Genomic Purification, y posteriormente se tipificaron dos polimorfismos (CAPN1-316 y CAPN1-4751) del gen CAPN1 mediante el método ARMS-PCR. La frecuencias alélicas y genotípicas, las heterocigosidades esperadas y observadas, así como, el índice FIS y el desequilibrio de ligamiento (LD) fueron calculadas mediante los programas MS-Tools y Genepop. Las frecuencias de los alelos asociados a mayor terneza para las poblaciones de CCH, CYA y CSV fueron: 23%, 22% y 33 % para el alelo C del SNP CAPN1-316 y 75%, 76% y 60% para el alelo C del CAPN1-4751. La heterocigocidad observada en las tres poblaciones se hallan en un rango de 0,30 a 0,46 para el marcador CAPN1-316 y de 0,21 a 0,60 para el polimorfismo CAPN1-4751. Los resultados demuestran que los bovinos criollos en las poblaciones analizadas poseen altas frecuencias alélicas para las variantes asociadas a mayor terneza de la carne. Por otra parte, no se observaron valores significativos de LD (P>0,01) entre los dos polimorfismos tipificados en las poblaciones estudiadas. Sería necesario tipificar ambos polimorfismos en futuros programas de selección asistida por marcadores genéticos.Meat tenderness is in part determined by the calpain (CAPN1) / calpastatin (CAST) genes. In the lowlands of Bolivia, three well differentiated Creole cattle populations can be distinguished: the Yacumeños, Chaqueños and Saavedreños. The main objective of this research was to determine the allelic and genotypic frequencies of two polymorphisms of the calpain gene in three Creole cattle populations in Bolivia. Blood samples of 28 Creole cattle from Chaqueño cattle (CCH), 85 from Yacumeño cattle (CYA) and 30 from Saavadreño cattle (CSV) were collected. Total DNA was extracted using the commercial kit Wizard® Genomic Purification and subsequently two polymorphisms (CAPN1-316 and CAPN1- 4751) of the CAPN1 gene were genotyped by the amplification refractory mutation system (ARMS-PCR) method. Allelic and genotypic frequencies, expected and observed heterozygosities, the FIS index and the magnitude of linkage disequilibrium (LD) were calculated using the software MS-Tools and Genepop. The allelic frequencies of variants associated with tenderness in the three populations CCH, CYA and CSV were 23%, 22% and 23% for the CAPN1- 316 and 75%, 76% and 60% for the CAPN1-4751. The observed heterozygosities in the three populations fluctuated between 0.30 and 0.46 for the CAPN1-316 marker and between 0.21 and 0.60 for the CAPN1-4751 marker. The results showed that the analysed populations of Creole cattle presented high frequencies of the alleles previously associated with tenderness in meat. The analysis of LD, however, did not show evidence of linkage between the two markers. It is necessary to perform a genetic analysis for both polymorphisms if included in future selection programs.Fil: Pereira, J. A. C.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Falomir Lockhart, Agustin Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Loza, A.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Villegas Castagnasso, Egle Etel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Rojas, P.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Carino, M. . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Ripoli, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Giovambattista, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentin

Anti-Allergic Cromones Inhibit Histamine and Eicosanoid Release from Activated Human and Murine Mast Cells by Releasing Annexin A1

PMCID: PMC3601088This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

No association between islet cell antibodies and coxsackie B, mumps, rubella and cytomegalovirus antibodies in non-diabetic individuals aged 7–19 years

Viral antibodies were tested in a cohort of 44 isletcell antibody-positive individuals age 7–19 years, and 44 of their islet cell antibody-negative age and sex-matched classmates selected from a population study of 4208 pupils who had been screened for islet cell antibodies. Anti-coxsackie B1-5 IgM responses were detected in 14 of 44 (32%) of the islet cell antibody-positive subjects and in 7 of 44 (16%) control subjects. This difference did not reach the level of statistical significance. None of the islet cell antibody-positive subjects had specific IgM antibodies to mumps, rubella, or cytomegalovirus. There was also no increase in the prevalence or the mean titres of anti-mumps-IgG or IgA and anti-cytomegalovirus-IgG in islet cell antibody-positive subjects compared to control subjects. These results do not suggest any association between islet cell antibodies, and possibly insulitis, with recent mumps, rubella or cytomegalo virus infection. Further studies are required to clarify the relationship between islet cell antibodies and coxsackie B virus infections