Chimerism studies in HLA-identical nonmyeloablative hematopoietic stem cell transplantation point to the donor CD8+ T-cell count on day +14 as a predictor of acute graft-versus-host disease

AbstractChimerism analysis of hematopoietic cells has emerged as an essential tool in nonmyeloablative hematopoietic stem cell transplantation. We have investigated the development of donor chimerism in granulocytes and CD4+ and CD8+ T cells in blood and bone marrow of 24 patients with hematologic malignancies who received HLA-identical sibling peripheral blood stem cell grafts after conditioning with fludarabine and 2 Gy of total body irradiation. The T-cell chimerism of blood and bone marrow was tightly correlated. Complete donor chimerism was reached earlier in the granulocytes than in the T cells. Mixed T-cell chimerism was common at the time of onset of acute graft-versus-host disease (aGVHD), and both CD4+ and CD8+ donor T-cell chimerism increased with the occurrence of aGVHD grades II to IV (P = .0002 and P = .019, respectively). The rate of disappearance of recipient CD8+ T cells was faster in patients with aGVHD grades II to IV than in patients without clinically significant aGVHD (P = .016). This observation indicates a role of graft-versus-lymphohematopoietic tissue reactions in creating complete donor T-cell chimerism. A donor CD8+ T-cell count above the median on day +14 increased the risk of subsequent development of aGVHD grades II to IV (P = .003)

Which Stroke Next? All Strokes Next! Part Two: Strokes for Intermediate and Advanced Swimmers

The primary goal of this two-part project is to answer the rhetorical question of which strokes should be taught first, and which later (Langendorfer, 2013, Stallman, 2014a). As you have seen in Part One, we emphasize (as have many others) the need for a firm foundation before any stroke is introduced. When the learner is ready for propulsive motor competencies, there is no stroke which suits all as their first. In Part One we explored the “beginning strokes” all of which are candidates for any given learner’s first stroke. We also argued that after mastering their very first stroke the learner should learn the other, “first strokes.” This also broadens the base for the learning of other strokes as the learner advances to intermediate and advanced levels. Here in Part Two, we explore additional strokes, chosen as essential because of some unique quality which makes them the best solution in some specific, potential risk situation. They should, therefore, be included in any comprehensive, proactive aquatic educational program

Observation of double radiative capture on pionic hydrogen

We report the first observation of double radiative capture on pionic hydrogen. The experiment was conducted at the TRIUMF cyclotron using the RMC spectrometer, and detected $\gamma$--ray coincidences following $\pi^-$ stops in liquid hydrogen. We found the branching ratio for double radiative capture to be $(3.05 \pm 0.27(stat.) \pm 0.31(syst.)) \times 10^{-5}$. The measured branching ratio and angle-energy distributions support the theoretical prediction of a dominant contribution from the $\pi \pi \to \gamma \gamma$ annihilation mechanism.Comment: 4 Pages, 4 Figures. accepted for publication in Phys. Rev. Let

Robust Bounds on Choosing from Large Tournaments

Tournament solutions provide methods for selecting the "best" alternatives from a tournament and have found applications in a wide range of areas. Previous work has shown that several well-known tournament solutions almost never rule out any alternative in large random tournaments. Nevertheless, all analytical results thus far have assumed a rigid probabilistic model, in which either a tournament is chosen uniformly at random, or there is a linear order of alternatives and the orientation of all edges in the tournament is chosen with the same probabilities according to the linear order. In this work, we consider a significantly more general model where the orientation of different edges can be chosen with different probabilities. We show that a number of common tournament solutions, including the top cycle and the uncovered set, are still unlikely to rule out any alternative under this model. This corresponds to natural graph-theoretic conditions such as irreducibility of the tournament. In addition, we provide tight asymptotic bounds on the boundary of the probability range for which the tournament solutions select all alternatives with high probability.Comment: Appears in the 14th Conference on Web and Internet Economics (WINE), 201

Bimetallic nickel and palladium complexes for catalytic applications

South Africa is a mineral-rich country and one area in which minerals can be very important is catalysis. Over an extended period of time, homogeneous catalysis has grown to become very useful, particularly in the chemical and pharmaceutical industries. The organometallic compounds required in the catalysis industry have advanced from metallocenes to an alternative in the form of α-diimines. Most α-diimines are prepared from iminopyridyl moieties and are most active with nickel and palladium transition metals. This review providesa history of homogeneous catalysis and a discussion on iminopyridines, with the main focus on the nickel and palladium complexes formed from them. There follows a discussion of the bimetallic nickel and palladium complexes in various catalytic applications such as Suzuki and Heck coupling, with the main focus on ethylene polymerisation. The limitations are addressed and possible solutions presented to overcome those challenges. Several reviews in the related topics are to be found in the literature but not the α-diimine with iminopyridines and bimetallic nickel and palladium metals

Crystal structure of 2-hydroxyimino-2-(pyridin-2-yl)-N′-[1-(pyridin-2-yl)ethylidene]acetohydrazide

The molecule of the title compound, C14H13N5O2, is approximately planar (r.m.s deviation for all non-H atoms = 0.093 Å), with the planes of the two pyridine rings inclined to one another by 5.51 (7)°. The oxime group is syn to the amide group, probably due to the formation of an intramolecular N—H...N hydrogen bond that forms an S(6) ring motif. In the crystal, molecules are linked by pairs of bifurcated O—H...(O,N) hydrogen bonds, forming inversion dimers. The latter are linked via C—H...O and C—H...N hydrogen bonds, forming sheets lying parallel to (502). The sheets are linked via π–π stacking interactions [inter-centroid distance = 3.7588 (9) Å], involving the pyridine rings of inversion-related molecules, forming a three-dimensional structure

2-(3,5-Dimethyl-1H-pyrazol-1-yl)-2-hydroxyimino-N′-[1-(pyridin-2-yl)ethylidene]acetohydrazide

In the title compound, C14H16N6O2, the dihedral angles formed by the mean plane of the acetohydrazide group [maximum deviation 0.0629 (12) Å] with the pyrazole and pyridine rings are 81.62 (6) and 38.38 (4)° respectively. In the crystal, molecules are connected by N—H...O and O—H...N hydrogen bonds into supramolecular chains extending parallel to the c-axis direction

2-(3,5-Dimethyl-1H-pyrazol-1-yl)-2-hydroxyimino-N0-[1-(pyridin-2-yl)ethylethylidene]

In the title compound, C14H16N6O2, the dihedral angles formed by the mean plane of the acetohydrazide group [maximum deviation 0.0629 (12) A˚ ] with the pyrazole and pyridine rings are 81.62 (6) and 38.38 (4) respectively. In the crystal, molecules are connected by N—HO and O—HN hydrogen bonds into supramolecular chains extending parallel to the c-axis direction.peerReviewe

Dioxomolybdenum(VI) complexes of hydrazone phenolate ligands -syntheses and activities in catalytic oxidation reactions

The new cis-dioxomolybdenum(VI) complexes [MoO2(L2)(H2O)] (2) and [MoO2(L3) (H2O)] (3) containing the tridentate hydrazone-based ligands (H2L2 = N'-(3,5-di-tert-butyl-2-hydroxybenzylidene)-4-methylbenzohydrazide and H2L3 = N'-(2-hydroxybenzylidene)-2-(hydroxyimino)propanehydrazide) have been synthesised and characterized via IR, 1H and 13C NMR spectroscopy, mass spectrometry, and single crystal X-ray diffraction analysis. The catalytic activities of complexes 2 and 3, and the analogous known complex [MoO2(L1)(H2O)] (1) (H2L1 = N'-(2-hydroxybenzylidene)-4-methylbenzohydrazide) have been evaluated for various oxidation reactions, viz. oxygen atom transfer from dimethyl sulfoxide to triphenylphosphine, and sulfoxidation of methyl-p-tolylsulfide or epoxidation of different alkenes using tert-butyl hydroperoxide as terminal oxidant. The catalytic activities were found to be comparable for all three complexes, but complexes 1 and 3 showed better catalytic performances than complex 2, which contains a more sterically demanding ligand than the other two complexes.peerReviewe