The human LASP1 gene is fused to MLL in an acute myeloid leukemia with t(11;17)(q23;q21)

The MLL gene at chromosome 11q23 is frequently rearranged in acute leukemia. Here we report the identification of a new MLL fusion partner in the case of an infant with AML-M4 and a t(11;17)(q23;q21) translocation. Fluorescence in situ hybridization (FISH) and RT-PCR analyses indicated a rearrangement of the MLL gene, but no fusion with previously identified MLL fusion partners at 17q, such as AF17 or MSF. Rapid amplification of cDNA ends (RACE) revealed an in-frame fusion of MLL to LASP1, a gene that is amplified and overexpressed in breast cancer. Retroviral transduction of myeloid progenitors demonstrated that MLL/LASP1 is the fourth known fusion of MLL with a cytoplasmic protein that has no in vitro transformation capability, thus establishing a potential subgroup among the MLL fusion proteins.     

Darstellung von phenolischen verbindungen und phenol/formaldehyd-polykondensaten mit ketoxim-, aldoxim- oder 1-methyl-4-hydroxyiminomethylpyridinium-gruppen und deren wirkung auf parathion-methyl® und verwandte verbindungen

Thirteen low molecular weight oximes were prepared: one derivative of acetophenone ( 1 ), two derivatives of benzophenone ( 2 and 3 ), two derivatives of salicylaldehyde containing two phenolic nuclei ( 4c and 5c ), and eight compounds in which a phenol unit is substituted by a 4-hydroxyiminomethylpyridiniummethyl group ( 8a–f, 10c , and 11c ). Besides these compounds polymeric phenol formaldehyde condensates were synthesized which contain units deriving from benzophenoneoxime ( 15b ) or from salicylaldehyde ( 22b ) and condensates containing 4-hydroxyiminomethylpyridiniummethyl groups ( 23c ). A series of low molecular weight and water soluble compounds ( 8a–f ) were proved as antidotes on mice which were poisoned by paraoxon, sarin, soman, or tabun. These compounds showed a distinct but only a little antidote activity in the case of soman and tabun. Adsorption studies of parathion-methyl in a solution of water and methanol (volume ratio 10:1) by the water insoluble polycondensates showed that the oximes adsorb better than the parent carbonyl products.     

Pair distribution function and pair potential of lattice model chains under theta conditions, 1. Numerical evaluation

Ensembles of unbranched non-selfintersecting 4-way cubic lattice chains consisting of 100 chains each occupying 50 lattice points have been developed for Θ-conditions by a Metropolis-Rosenbluth-Monte-Carlo technique using a kind of square well potential to describe the segment-segment interaction. For these equilibrated ensembles the pair distribution function G(R) and the average pair potential U(R) have been estimated by calculating the intermolecular energy for all isolated pairs, which can be depicted from the ensemble, as a function of the distance of the centers of gravity R of the two chains. The resulting G(R) being less than one for small R and exceeding one for large R does not correspond to that of an ideal gas. This means that for thermodynamic reasons alone there can be no free interpenetration of chains at the Θ-point. U(R) can be split into a repulsive and an attractive part both being approximately Gaussian in type. Thus, U(R) at the Θ-point can be represented by the general expression. with A>A′ and a>a′.     

Unusual pulmonary vascular lesions after intravenous injections of microcrystalline cellulose

Summary We present the morphological features of a case of fatal pulmonary granulomatosis from illicit intravenous injections of microcrystalline cellulose derived from pentazocine tablets. Extensive foreign body granulomas were found in the lumena and walls of pulmonary vessels and in the pulmonary interstitium. Previously unreported gaps containing foreign material were found in the walls of medium-sized muscular pulmonary arteries. This peculiar finding is discussed in the light of the possible mechanisms involved in the removal of embolized foreign material.     

Cationic polymerization of bis(1-alkylvinyl)benzenes and related monomers, 5. New thermostable polyindanes

The cationic cyclopolymerization of six monomers of the type “1,4-bis(alk-2-en-2-yl)benzene” is described. The length of the unsaturated chains of the monomers ranges from 3 (propenyl) to 8 (octenyl) carbon atoms. The polymerization yields polyindanes containing different isomeric indane structure elements, which have alkyl substituents ranging from methyl to hexyl groups. The number of carbon atoms in the alkyl side chains greatly influences the glass transition temperature T_g, which is depressed from 246°C (methyl-substituted polyindane) to 26°C (hexyl-substituted polyindane). Thermal stability is also affected, though far less than T_g: the temperature, at which the material has lost 2% of its original weight is lowered from 420°C to 340°C. The polyindanes are soluble in a number of organic solvents. Their degree of polymerization is limited by a side reaction which provides non-reactive end groups. Thus, the number-average molar masses obtained are between 2800 and 4300 g/mol.     

Basic studies on the inifer mechanism, 1. Interaction of 1,4-bis(1-chloro-1-methylethyl)benzene with BCl3

A mixture of 1,4-bis(1-chloro-1-methylethyl)benzene ( 1 ) and BCl₃ at ?80°C in CH₂Cl₂ yields a red colour, which is explained as a result of the formation of a charge transfer (CT) complex between the carbenium ion formed after Cl^? abstraction from 1 and the aromatic π-system of 1 . This view is supported by UV/VIS and conductivity measurements. These measurements and their consequences for the cationic polymerization are discussed in detail.     

The laser-flash-initiated polymerization as a tool of evaluating (individual) kinetic constants of free-radical polymerization, 2. The direct determination of the rate of constant of chain propagation

When a polymerizable system is subjected to periodic light flashes, which induce the formation of primary radicals, a pseudostationary state is established which is characterized by a periodic profile of the (polymer) radical concentration. Within such a period of length t₀ the radical concentration will decay according to a second-order rate law. At the end of this period the radicals, which have escaped termination up to this moment, have propagated up to a chain length L₀ = t₀·k_p·c_M, k_p representing the propagation rate constant and c_M the monomer amount concentration. When the next flash arrives these radicals are opposed to a strongly increased overall concentration of radicals which leads to an enhanced probability for their termination. As a consequence the formation of dead polymer molecules with a chain length close to L₀ is favoured. The chain-length distribution of polystyrene prepared under such pseudostationary conditions, which was evaluated by gel permeation chromatography, in fact exhibits such a peak. The analysis of the theoretical distribution curves, derived in this communication, reveals that it is easily possible to correlate this peak to L₀, independently of the mode of termination (disproportionation or combination). Thus, a method of evaluating k_p is derived without any reference to the termination rate constant k_t and largely independent of all features which usually cause problems in the evaluation of k_p and k_t (such as primary radical termination etc.). The experimental results agree fairly well with the data reported in literature, especially with those obtained from the number of particles and the rate of polymerization in emulsion systems.     

Azoinitiatoren, 10. Co- und terpolymerisation von butadien und styrol mit phenyl(3-vinylphenylazo)sulfid

Phenyl(3-vinylphenylazo)sulfide ( 2 )—displaying not only the properties of an initiator (thermolysis) and a monomer (vinyl group) but also of a chain transfer agent (sulfenyl group)–was copolymerized with styrene in emulsion at 40°C and in bulk at 50°C. Terpolymerization with styrene and butadiene at 5°C in emulsion led to azo-containing unsaturated polymers, which could be used for self crosslinking.     

Relative reaction probabilities in polymer-polymer reactions, 1. Investigations with Monte-Carlo model chains

Pairs of chains taken from ensembles of five-way cubic lattice chains (athermal or theta) were analysed for the (relative) probability of contact formation between specified segments belonging to different chains within this pair. This probability may be taken as a measure of the rate constant which characterizes bimolecular polymer-polymer reactions which occur between active sites attached to or localized at these segments, relative to the reaction between the same active sites, if these were not bound to the polymer chains. It turns out that the (expected) effect which results from the interaction between the chains as a whole (external shielding) is of comparatively small extent and is fairly independent of chain length. The much more important contribution, however, is made by a novel phenomenon which — exhibiting a strong dependence on chain length n — is responsible for an “internal” shielding: the compatible pair configurations (i. e. those which are free of intermolecular intersections) are characterized by largely increased segment-segment distances. As a consequence, the probability of contact formation is much lower than it would be expected from a convolution of the (mutually independent) radial distributions of the segments participating in contact formation. The overall shielding factor K can be represented as a product of the fairly independent contributions of external (K_G) and internal (K_w) shielding. The overall chain length dependence is described by a power law K = Dn^d, where the exponent d depends on whether two (Type I contacts), one (Type II) or no endsegment at all (Type III) is involved in contact formation. For athermal chains the exponents are d = ?0,16 (Type I), d = ?0,30 (Type II), and d = ?0,50 (Type III), the pre-factor being of the order of unity throughout. Θ-systems roughly show the same general characteristics as the athermal ones, however, to a lesser extent. Thus, neither shielding nor its chain length dependence vanish, the exponents being about ?0,06 (Type I), ?0,1 (Type II), and ?0,2 (Type III), respectively.     

Optic disc topography and short-term increase in intraocular pressure

Intraocular pressure is intra- and interindividually inconstant. It is influenced by numerous ocular and general factors. We evaluated the question as to whether a short-term increase in intraocular pressure might change the two-dimensional topography of the optic nerve head. Optic disc photographs of 63 glaucomatous eyes in 33 Caucasian patients and 39 normal eyes in 22 subjects were taken at a baseline intraocular pressure of <20 mm Hg and at 1 and 8 s after pressure elevations of 10 and 20 mm Hg. No significant differences in the size and form of the optic disc, optic cup, neuroretinal rim, peripapillary scleral ring or parapapillary chorioretinal atrophy were found. The retinal vessels mostly reacted to the intraocular pressure elevation by an initial decrease and subsequent re-increase in their diameter; this change was significant (P<0.05) for the pressure elevation of 20 mm Hg. We conclude that the two-dimensional optic disc topography is not significantly changed by a short-term increase in intraocular pressure.