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Background: Bioimpedance devices are practical for measuring body composition in preschool children, but their application is limited by the lack of validated equations. Objectives: To develop and validate fat-free mass (FFM) bioimpedance prediction equations among New Zealand 3.5-year olds, with dual-energy X-ray absorptiometry (DXA) as the reference method. Methods: Bioelectrical impedance spectroscopy (SFB7, ImpediMed) and DXA (iDXA, GE Lunar) measurements were conducted on 65 children. An equation incorporating weight, sex, ethnicity, and impedance was developed and validated. Performance was compared with published equations and mixture theory prediction. Results: The equation developed in ~70% (n= 45) of the population (FFM [kg] = 1.39 + 0.30 weight [kg] + 0.39 length2/resistance at 50 kHz [cm2/Ω] + 0.30 sex [M = 1/F = 0] + 0.28 ethnicity [1 = Asian/0 = non-Asian]) explained 88% of the variance in FFM and predicted FFM with a root mean squared error of 0.39 kg (3.4% of mean FFM). When internally validated (n= 20), bias was small (40 g, 0.3% of mean FFM), with limits of agreement (LOA) ±7.6% of mean FFM (95% LOA: –0.82, 0.90 kg). Published equations evaluated had similar LOA, but with marked bias (>12.5% of mean FFM) when validated in our cohort, likely due to DXA differences. Of mixture theory methods assessed, the SFB7 inbuilt equation with personalized body geometry values performed best. However, bias and LOA were larger than with the empirical equations (–0.43 kg [95% LOA: –1.65, 0.79], p< 0.001). Conclusions: We developed and validated a bioimpedance equation that can accurately predict FFM. Further external validation of the equation is required.

In this paper, we introduce an innovative parameter that allows us to evaluate the so-called “relevant colors” in a painting; in other words, the number of colors that would stand out for an observer when just glancing at a painting. These relevant colors allow us to characterize the color palette of a scene and, on this basis, those discernible colors that are colorimetrically different within the scene. We tried to carry out this characterization of the chromatic range of paints according to authors and styles. We used a collection of 4,266 paintings by 91 painters, from which we extracted various parameters that are exclusively colorimetric to characterize the range of colors. After this refinement of the set of selected colors, our algorithm obtained an average number of 18 relevant colors, which partially agreed with the total 11–15 basic color names usually found in other categorical color studies.

To observe trends in surgical techniques for corneal transplantation and main indications in our hospital over the past five years.

Dr. Maria A. Oquendo and others identified some of the barriers that limit research among ethnic and cultural groups ("Diversity Missing From Research," May 2008, p. 1). I would like [...]

[Re. 'War and Healing,' by Dr. Gerry Greenstone, March:] I have always thought Captain James Lind introduced limes as the initial successful therapy for scurvy, and that is why the [...]

The sphingosine-1-phosphate receptor-1 (S1P1) agonist ozanimod ameliorates ulcerative colitis, yet its mechanism of action is unknown. Here, we examine the cell subsets that express S1P1in intestine using S1P1-eGFP mice, the regulation of S1P1expression in lymphocytes after administration of dextran sulfate sodium (DSS), after colitis induced by transfer of CD4+CD45RBhicells, and by crossing a mouse with TNF-driven ileitis with S1P1-eGFP mice. We then assayed the expression of enzymes that regulate intestinal S1P levels, and the effect of FTY720 on lymphocyte behavior and S1P1expression. We found that not only T and B cells express S1P1, but also dendritic (DC) and endothelial cells. Furthermore, chronic but not acute inflammatory signals increased S1P1expression, while the enzymes that control tissue S1P levels in mice and humans with inflammatory bowel disease (IBD) were uniformly dysregulated, favoring synthesis over degradation. Finally, we observed that FTY720 reduced T-cell velocity and induced S1P1degradation and retention of Naïve but not effector T cells. Our data demonstrate that chronic inflammation modulates S1P1expression and tissue S1P levels and suggests that the anti-inflammatory properties of S1PR agonists might not be solely due to their lymphopenic effects, but also due to potential effects on DC migration and vascular barrier function.

Spanish continental soldiers were ill prepared for the environmental conditions they encountered in the first of three wars for Cuban independence. The disease fatality rate was over 80% with yellow fever the most prevalent disease. Another 7% of these soldiers died in battle or from their combat wounds.

The purpose of this research was to determine the potential use of water-soluble anionic and cationic carbosilane dendrimers (generations 1–3) as mucoadhesive polymers in eyedrop formulations. Cationic carbosilane dendrimers decorated with ammonium –NH3+groups were prepared by hydrosylilation of Boc-protected allylamine and followed by deprotection with HCl. Anionic carbosilane dendrimers with terminal carboxylate groups were also employed in this study. In vitroand in vivotolerance studies were performed in human ocular epithelial cell lines and rabbit eyes respectively. The interaction of dendrimers with transmembrane ocular mucins was evaluated with a surface biosensor. As proof of concept, the hypotensive effect of a carbosilane dendrimer eyedrop formulation containing acetazolamide (ACZ), a poorly water-soluble drug with limited ocular penetration, was tested after instillation in normotensive rabbits. The methodology used to synthesize cationic dendrimers avoids the difficulty of obtaining neutral –NH2dendrimers that require harsher reaction conditions and also present high aggregation tendency. Tolerance studies demonstrated that both prototypes of water-soluble anionic and cationic carbosilane dendrimers were well tolerated in a range of concentrations between 5 and 10 μM. Permanent interactions between cationic carbosilane dendrimers and ocular mucins were observed using biosensor assays, predominantly for the generation-three (G3) dendrimer. An eyedrop formulation containing G3 cationic carbosilane dendrimers (5 μM) and ACZ (0.07%) (289.4 mOsm; 5.6 pH; 41.7 mN/m) induced a rapid (onset time 1 h) and extended (up to 7 h) hypotensive effect, and led to a significant increment in the efficacy determined by AUC08hand maximal intraocular pressure reduction. This work takes advantage of the high-affinity interaction between cationic carbosilane dendrimers and ocular transmembrane mucins, as well as the tensioactive behavior observed for these polymers. Our results indicate that low amounts of cationic carbosilane dendrimers are well tolerated and able to improve the hypotensive effect of an acetazolamide solution. Our results suggest that carbosilane dendrimers can be used in a safe range of concentrations to enhance the bioavailability of drugs topically administered in the eye.

RPA correlations, spectral function and 2p2h (multi-nucleon) effects on charged-current neutrino-nucleus reactions without emitted pions are discussed. We pay attention to the influence of RPA and multi-nucleon mechanisms on the MiniBooNE and MINERvA flux folded differential cross sections, the MiniBooNE flux unfolded total cross section and the neutrino energy reconstruction.

We perform a theoretical analysis of the Λb → J/ΨK- p reaction from where a recent LHCb experiment extracts a Λ(1405) contribution in the K- p spectrum close to threshold and two baryon states of hidden charm in the J/Ψp spectrum. We recall that baryon states of this type have been theoretically predicted matching the mass, width and JP of the experiment; concretely some states built up from the J/ΨN, D¯* Λc, D¯*Σc, D¯Σc,* and D¯*Σc* coupled channels. We assume that the observed narrow state around 4450 MeV has this nature and we are able to describe simultaneously the shapes and relative strength of the the K- p mass distribution close to threshold and the peak of the J/Ψp distribution, with values of the J/Ψp coupling to the resonance in line with the theoretical ones. The nontrivial matching of many properties gives support to a JP = 3/2- assignment to this state and to its nature as a molecular state mostly made of D¯*Σc and D¯*Σc*. [ABSTRACT FROM AUTHOR]

Having recently participated as a guest on a radio program about mental health issues, I read with great interest Dr. Paul J. Fink's recent column ("Radio Psychiatry," Fink! Still at [...]

Community-based case management is now the preferred treatment approach for those psychiatric patients who suffer from severe mental illness and live in the community. Intensive case managers perform a variety [...]

The analysis of hadronic interactions with effective field theory techniques is complicated by the appearance of a large number of low-energy constants, which are usually fitted to data. On the other hand, the large-Nc limit helps to impose natural short-distance constraints on these low-energy constants, providing a parameter reduction. A Bayesian interpretation of the expected 1/Nc accuracy allows for an easy and efficient implementation of these constraints, using an augmentedX². We apply this approach to the analysis of meson-meson scattering, in conjunction with chiral perturbation theory to one loop and coupled-channel unitarity, and show that it helps to largely reduce the many existing ambiguities and simultaneously provide an acceptable description of the available phase shifts. [ABSTRACT FROM AUTHOR]

I read "Medical School Applications Again on the Rise," but I am concerned that this trend does not appear to be reversing for minorities (November 2003, p. 6). At Eastern [...]

We extend to 10 GeV results from a microscopic calculation of charged-current neutrino-nucleus reactions that do not produce a pion in the final state. For the class of events coming from neutrino interactions with two nucleons producing two holes (2p2h), limiting the calculation to three-momentum transfers less than 1.2 GeV produces a two-dimensional distribution in momentum and energy transfer that is roughly constant as a function of energy. The cross section for 2p2h interactions approximately scales with the number of nucleons for isoscalar nuclei, similar to the quasi-elastic cross section. When limited to momentum transfers below 1.2 GeV, the cross section is 26% of the quasi-elastic cross section at 3 GeV, but 14% if we neglect a ∆1232 resonance absorption component. The same quantities are 33% and 17% for antineutrinos. For the quasi-elastic interactions, the full nuclear model with long range correlations produces an even larger, but approximately constant distortion of the shape of the four-momentum transfer at all energies above 2 GeV. The 2p2h enhancement and long-range correlation distortions to the cross section for these interactions are significant enough they should be observable in precision experiments to measure neutrino oscillations and neutrino interactions at these energies, but also balance out and produce less total distortion than each effect does individually. [ABSTRACT FROM AUTHOR]

This paper examines the formation and stability of nano-complexes that could provide a new therapeutic approach against HIV-1 infection. Poly(propylene imine) glycodendrimers decorated with 2nd generation cationic carbosilane dendrons were generated and their use in polyplex formation checked. Owing to their positively-charged terminal amino groups the hybrid glycodendrimers can bind anionic peptides. It was shown that they form nano-complexes with the HIV-derived peptides P24, Gp160 and Nef. Complexes 130-190 nm in size were formed in molar ratios (dendrimer/ peptide) of (3-4):1. These were sufficiently stable over time and at different pHs. The results obtained suggest that the hybrid dendrimers studied can be considered as alternative carriers for delivering HIV peptides to dendritic cells.

We present a coupled channel unitary approach to obtain states dynamically generated from the meson-baryon interaction with hidden charm, using constraints of heavy quark spin symmetry. As a basis of states, we use DB, D∗B states, with B baryon charmed states belonging to the 20 representations of SU(4) with JP=1/2+, 3/2+. In addition we also include the ηcN and J/ΨN states. The inclusion of these coupled channels is demanded by heavy quark spin symmetry, since in the large mQ limit the D and D∗ states are degenerate and are obtained from each other by means of a spin rotation, under which QCD is invariant. The novelty in the work is that we use dynamics from the extrapolation of the local hidden gauge model to SU(4), and we show that this dynamics fully respects the constraints of heavy quark spin symmetry. With the full space of states demanded by the heavy quark spin symmetry and the dynamics of the local hidden gauge, we look for states dynamically generated and find four basic states that are bound, corresponding to DΣc, DΣc∗, D∗Σc, and D∗Σc∗, decaying mostly into ηcN and J/ΨN. All the states appear in isospin I=1/2, and we find no bound states or resonances in I=3/2. The DΣc state appears in J=1/2 and the DΣc∗ in J=3/2; the D∗Σc appears nearly degenerate in J=1/2, 3/2 and the D∗Σc∗ appears nearly degenerate in J=1/2, 3/2, 5/2, with the peculiarity that in J=5/2 the state has zero width in the space of states chosen. All the states are bound with about 50 MeV with respect to the corresponding DB thresholds, and the width, except for the J=5/2 state, is also of the same order of magnitude. Finally, we discuss the uncertainties stemming from the expected breaking of SU(4) and the heavy quark spin symmetry. [ABSTRACT FROM AUTHOR]

We study lπ production in both charged and neutral current neutrino-nucleus scattering for neutrino energies below 2 GeV. We use a theoretical model for one pion production at the nucleon level that we correct for medium effects. The results are incorporated into a cascade program that apart from production also includes the pion final state interaction inside the nucleus. Besides, in some specific channels coherent IT production is also possible and we evaluate its contribution as well. Our results for total and differential cross sections are compared with recent data from the Mini BooNE Collaboration. The model provides an overall acceptable description of the data, better for neutral-current than for charged-current channels, although the theory is systematically below the data. Differential cross sections, folded with the full neutrino flux, show that most of the missing pions lie in the forward direction and at high energies. [ABSTRACT FROM AUTHOR]

A model is developed to describe odd-parity baryon resonances generated dynamically through a unitary baryon-meson coupled-channels approach. The scheme applies to channels with light- and/or heavy-quark content. Distinct features of the model are that i) the interaction is an S-wave contact one, ii) it reduces to the SU(3) Weinberg-Tomozawa Hamiltonian when light pseudoscalar mesons are involved, thus respecting chiral symmetry, iii) spin-flavor is preserved in the light-quark sector, and iv) heavy-quark spin symmetry is fulfilled in the heavy-quark sector. In particular, baryon-meson states with different content in c or in c̅ do not mix. The model is a minimal one and it contains no free parameters. In this work, we focus on baryon resonances with hidden charm (at least one c̅ and one c quark). We analyze several possible sectors and, for the sector with zero net charm, we write down the most general Lagrangian consistent with SU(3) and heavy-quark spin symmetry. We explicitly study the N and Δ states, which are produced from the S-wave interaction of pseudoscalar and vector mesons with 1/2+ and 3/2+ baryons within the charmless and strangeless hidden-charm sector. We predict seven odd-parity N-like and five Δ-like states with masses around 4 GeV, most of them as bound states. These states form heavy-quark spin multiplets, which are almost degenerate in mass. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and they might be looked for in the forthcoming PANDA experiment at the future FAIR facility. [ABSTRACT FROM AUTHOR]

We propose an effective field theory incorporating light SU(3)-flavor and heavy quark spin symmetry to describe charmed meson-antimeson bound states. At lowest order the effective field theory entails a remarkable simplification: it only involves contact range interactions among the heavy meson and antimeson fields. We show that the isospin violating decays of the X(3872) can be used to constrain the interaction between the D and a D̅* mesons in the isovector channel. As a consequence, we can rule out the existence of an isovector partner of the X(3872). If we additionally assume that the X(3915) and Y(4140) are D*D̅* and Ds*D̅s* molecular states, we can determine the full spectrum of molecular states with isospin I=0, ½ and 1. [ABSTRACT FROM AUTHOR]

The LHCb Collaboration has recently observed two narrow baryon resonances with beauty. Their masses and decay modes look consistent with the quark model orbitally excited states Λb(5912) and Λb"(5920), with quantum numbers JP=½- and 3/2-, respectively. We predict the existence of these states within a unitarized meson-baryon coupled-channel dynamical model, which implements heavy-quark spin symmetry. Masses, quantum numbers and couplings of these resonances to the different meson-baryon channels are obtained. We find that the resonances Λb0(5912) and Λb0(5920) are heavy-quark spin symmetry partners, which naturally explains their approximate mass degeneracy. Corresponding bottom-strange baryon resonances are predicted at Ξb(6035.4) (JP=½-) and Ξb(6043.3) (JP=3/2-). The two ?b and two Ξb resonances complete a multiplet of the combined symmetry SU(3)-flavor times heavy-quark spin. [ABSTRACT FROM AUTHOR]

We explore the consequences of heavy quark spin symmetry for the charmed meson-antimeson system in a contact-range (or pionless) effective field theory. As a trivial consequence, we theorize the existence of a heavy quark spin symmetry partner of the X(3872), with Jpc = 2++, which we call X(4012) in reference to its predicted mass. If we additionally assume that the X(3915) is a 0++ heavy spin symmetry partner of the X(3872), we end up predicting a total of six D(*)¯D(*)W molecular states. We also discuss the error induced by higher order effects such as finite heavy quark mass corrections, pion exchanges and coupled channels, allowing us to estimate the expected theoretical uncertainties in the position of these new states. [ABSTRACT FROM AUTHOR]

We show that because of the multinucleon mechanism effects, the algorithm used to reconstruct the neutrino energy is not adequate when dealing with quasielastic-like events, and a distortion of the total flux-unfolded cross-section shape is produced. This amounts to a redistribution of strength from high to low energies, which gives rise to a sizable excess (deficit) of low (high) energy neutrinos. This distortion of the shape leads to a good description of the MiniBooNE unfolded charged current quasielastic-like cross sections published by A. A. Aguilar-Arevalo et al. [(MiniBooNE Collaboration), Phys. Rev. D 81, 092005 (2010)]. However, these changes in the shape are artifacts of the unfolding process that ignores multinucleon mechanisms. [ABSTRACT FROM AUTHOR]

Leptin (LEP) is a cytokine-like hormone proven to be involved in diverse biological processes. In livestock, it regulates feed intake, BW homeostasis, and energy balance, among other traits. Natural nonsynonymous genetic polymorphisms in the ovine leptin (oLEP) alter the biochemical and physiological characteristics of its gene products. Here we studied in vitro and in vivo the biochemical and physiological characteristics of recombinant hormones representing the oLEPand bovine leptin (bLEP) reference sequences of wild-type (WT) leptins (GenBank accession No. U84247 and U50365, respectively), oLEP and bLEP recombinant muteins carrying the R4C mutation, and oLEP recombinant hormones carrying the A59V and Q62R mutations, which were detected in bLEP. All proteins were purified to homogeneity as monomers and formed 1:1 molar ratio complexes with the chicken leptin-binding domain (LBD). Surface plasmon resonance experiments revealed that all protein variants exhibit reduced (P< 0.05) affinity to chicken (ch) and human (h) LBD compared with the WT oLEP and bLEP recombinant proteins. The ovine and bovine R4C muteins exhibited significantly (P< 0.05) greater induction of cell proliferation in a Baf/3 cell line bioassay, despite lower affinity toward both hLBD and chLBD. Intra-third cerebral ventricle infusion of oLEP and its 3 muteins in sheep resulted in reduced feed intake. However, the 3 tested muteins had a decreased (P< 0.05) inhibitory effect than the WT LEP. It was concluded that natural genetic polymorphisms in the bLEPare associated with variation in the biochemical and physiological properties of the protein.

We construct ππ amplitudes that fulfill exact elastic unitarity, account for one-loop chiral perturbation theory contributions and include all 1/NC leading terms, with the only limitation of considering just the lowest-lying nonet of exchanged resonances. Within such a scheme, the NC dependence of σ and ρ masses and widths is discussed. Robust conclusions are drawn in the case of the ρ resonance, confirming that it is a stable meson in the limit of a large number of QCD colors, NC. Less definitive conclusions are reached in the scalar-isoscalar sector. With the present quality of data, we cannot firmly conclude whether or not the NC = 3 f0(600) resonance completely disappears at large NC or if it has a subdominant component in its structure, which would become dominant for a number of quark colors sufficiently large. [ABSTRACT FROM AUTHOR]

We present results for the strong widths corresponding to the Σ → Λbπ and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed decays. We apply our model from Phys. Rev. D 72, 094022 (2005), where we previously studied the corresponding transitions in the charmed sector. Our nonrelativistic constituent quark model uses wave functions that take advantage of the constraints imposed by heavy quark symmetry. The partial conservation of axial current hypothesis allows us to determine the strong vertices from an analysis of the axial current matrix elements. [ABSTRACT FROM AUTHOR]

We discuss the possibility and the description of bound states between B and B̄mesons. We argue that the existence of such a bound state can be deduced from (i) the weakly bound X(3872) state, (ii) certain assumptions about the short-range dynamics of the DD̄* system and (iii) heavy quark symmetry. From these assumptions the binding energy of the possible BB̄* bound states is determined, first in a theory containing only contact interactions which serves as a straightforward illustration of the method, and then the effects of including the one-pion exchange potential are discussed. In this latter case three isoscalar states are predicted: a positive and negative C-parity ³S1 - ³D1 state with a binding energy of 20 MeV and 6 MeV below threshold, respectively, and a positive C-parity ³P0 shallow state located almost at the BB̄* threshold. However, large uncertainties are generated as a consequence of the l/mQ corrections from heavy quark symmetry. Finally, the newly discovered isovector Zb(10610) state can be easily accommodated within the present framework by a minor modification of the short-range dynamics. [ABSTRACT FROM AUTHOR]

In this paper we develop a formalism to evaluate wave functions in momentum and coordinate space for the resonant states dynamically generated in a unitary coupled channel approach. The on-shell approach for the scattering matrix, commonly used, is also obtained in quantum mechanics with a separable potential, which allows one to write wave functions in a trivial way. We develop useful relationships among the couplings of the dynamically generated resonances to the different channels and the wave functions at the origin. The formalism provides an intuitive picture of the resonances in the coupled channel approach, as bound states of one bound channel, which decays into open ones. It also provides an insight and practical rules for evaluating couplings of the resonances to external sources and how to deal with final state interaction in production processes. As an application of the formalism we evaluate the wave functions of the two Ε(1405) states in the πΣ, K N, and other coupled channels. It also offers a practical way to study three-body systems when two of them cluster into a resonance. [ABSTRACT FROM AUTHOR]

Lymphocytes involved in intestinal immune response are found in organized immune inductive sites of the gut-associated lymphoid tissues (GALT) such as Peyer's patches (PP), mesenteric lymph nodes (MLN) and diffuse effector sites of gut epithelium and lamina propria (LP). β7 integrins are responsible for efficient trafficking and retention of lymphocytes in these sites. Na- and effector lymphocytes use α4β7 integrin to extravasate from blood to gut mucosal tissues of GALT, MLN and LP via interactions with Mucosal Addressin Cell Adhesion Molecule-1 (MAdCAM-1). The αEβ7 integrin facilitates retention of effector and memory lymphocytes in the gut epithelial layer via interactions with E-cadherin. Mucosal dendritic cells (DCs) regulate the expression of the gut homing receptors α4β7 integrin and the chemokine receptor CCR9 on activated effector and regulatory lymphocytes in a retinoic acid-dependent manner. CD103 (αE integrin) identifies a subset of mucosal DCs in MLN and small intestine LP that have an enhanced ability to induce gut-tropic receptors on responding lymphocytes. The interactions between β7 integrin and their ligands are also implicated in the pathogenesis and progression of inflammatory bowel diseases (IBDs), intestinal parasitic infections and graft-versus-host diseases. During intestinal inflammation, β7 integrin-dependent and - independent pathways contribute to lymphocytes recruitment to the intestinal tissues and disease pathogenesis. Recent works have explored the potential of therapeutic targeting of α4 and β7 integrins in IBDs. Here, we review the current understanding of the role of β7 integrins in intestinal lymphocyte trafficking and retention in health and disease.

Lymphocytes involved in intestinal immune response are found in organized immune inductive sites of the gut-associated lymphoid tissues (GALT) such as Peyers patches (PP), mesenteric lymph nodes (MLN) and diffuse effector sites of gut epithelium and lamina propria (LP). 7 integrins are responsible for efficient trafficking and retention of lymphocytes in these sites. Naïve and effector lymphocytes use 47 integrin to extravasate from blood to gut mucosal tissues of GALT, MLN and LP via interactions with Mucosal Addressin Cell Adhesion Molecule-1 (MAdCAM-1). The E7 integrin facilitates retention of effector and memory lymphocytes in the gut epithelial layer via interactions with E-cadherin. Mucosal dendritic cells (DCs) regulate the expression of the gut homing receptors 47 integrin and the chemokine receptor CCR9 on activated effector and regulatory lymphocytes in a retinoic acid-dependent manner. CD103 (E integrin) identifies a subset of mucosal DCs in MLN and small intestine LP that have an enhanced ability to induce gut-tropic receptors on responding lymphocytes. The interactions between 7 integrin and their ligands are also implicated in the pathogenesis and progression of inflammatory bowel diseases (IBDs), intestinal parasitic infections and graft-versus-host diseases. During intestinal inflammation, 7 integrin-dependent and - independent pathways contribute to lymphocytes recruitment to the intestinal tissues and disease pathogenesis. Recent works have explored the potential of therapeutic targeting of 4 and 7 integrins in IBDs. Here, we review the current understanding of the role of 7 integrins in intestinal lymphocyte trafficking and retention in health and disease.

The first terminal rhenium phosphinidene complex, [Re(CO)5(η¹-PNⁱPr2)][AlCl4], has been synthesized by chloride abstraction from [Re(CO)5{P(Cl)(NⁱPr2)}]. The electrophilic character of the terminal phosphinidene ligand is demonstrated by phosphine addition at the unsaturated phosphorus center and by novel reactions with azobenzene, PhN&dbd;NPh, which generate, via C−H activation and P−N and P−C bond formation, coordinated benzodiazaphosphole ligands. The cations [Re(CO)5P(PPh3)NⁱPr2]⁺ and [Re(CO)5{P(PhNNHC6H4)NⁱPr2}]⁺ have been crystallographically characterized as their AlCl4^- salts. The corresponding late-metal terminal phosphinidene complexes [Co(CO)3(PR3)(η¹-PNⁱPr2)][AlCl4] (R = Ph, Et) also afford coordinated benzodiazaphospholes via reaction with PhN&dbd;NPh.

Hydrolysis of Ta−Cl or Ta−C bonds with the water-coordinated adduct [H2O·B(C6F5)3] allowed the synthesis of borane-stabilized complexes [TaCp*R2{O·B(C6F5)3}] (R = Cl, CH2Ph, Me) with a tantalum−oxo multiple bond. The chloro derivative in the presence of pyridine releases the adduct [py·B(C6F5)3] with formation of the oxo-bridged compound [TaCp*Cl2(μ-O)]2. DFT calculations have been carried out to determine the electronic properties of the Ta−O and O−B bonds.

Background & Aims: Strict T"H1 polarization is believed to underlie the pathogenesis of intestinal inflammation in Crohn's disease. In the present study we tested the hypothesis that T"H2 cytokines also may participate in disease development in SAMP1/YitFc mice that spontaneously develop terminal ileitis with perianal manifestations. Methods: Cytokine messenger RNA (mRNA) expression was studied by real-time polymerase chain reaction (PCR). Lamina propria mononuclear cells (LPMCs) were purified and stimulated cytokine secretion was analyzed. Blockade of interferon (IFN)-@c or interleukin (IL)-4 was performed by using specific neutralizing monoclonal antibodies (MAbs). CD4+/IL-4-secreting lymphocytes were purified from SAMP1/YitFc mesenteric lymph nodes (MLNs) and their ability to induce ileitis was tested after transfer to SCID recipients. Results: Initiation of ileitis in SAMP1/YitFc mice was T"H1-mediated because up-regulation of IFN-@c and tumor necrosis factor (TNF) preceded the histologic injury, whereas IFN-@c neutralization prevented the development of chronic inflammation (P < .005) by interfering with the expansion of lymphocytes. In contrast, the establishment of chronic ileitis coincided with significant increases in IL-5 (35x) and IL-13 (29x) mRNA expression (P < .005), as well as in T"H2 cytokine secretion by lamina propria lymphocytes (P < .05 vs. AKR controls). IL-4 blockade diminished IFN-@c mRNA expression and significantly ameliorated the severity of established ileitis (P < .05) by decreasing the histologic indices for villous distortion and active inflammation. In addition, IL-4 augmented the in vitro IFN-@c secretion by lymphocytes, whereas IL-4-secreting CD4+ lymphocytes were sufficient for adoptively transferring ileitis to SCID recipients. Conclusions: Our results indicate that both T"H1 and T"H2 pathways mediate Crohn's-like ileitis and suggest that combined T"H1/T"H2 manipulation may offer a therapeutic advantage for the treatment of Crohn's disease.

The Quasi-Elastic (QE) contribution of the nuclear inclusive electron model developed in reference [Nucl. Phys. A627 (1997) 543; ibidem Nucl. Phys. A627 (1997) 598] is extended to the study of electroweak Charged Current (CC) induced nuclear reactions at intermediate energies of interest for future neutrino oscillation experiments. Long range nuclear (RPA) correlations, Final State Interaction (FSI) and Coulomb corrections are included within the model. RPA correlations are shown to play a crucial role in the whole range of neutrino energies, up to 500 MeV, studied in this work. Predictions for inclusive muon capture for different nuclei through the Periodic Table and for the reactions and near threshold are also given. [Copyright &y& Elsevier]

Gastrointestinal complications are common in patients with renal failure and result in significant morbidity and mortality. Systemic calciphylaxis is an uncommon complication of renal failure, characterized by disseminated intravascular calcification and associated with progressive vascular compromise. We describe the case of a 63-year-old woman who presented with abdominal pain, elevated transaminases, and skin manifestations consistent with a vasculitic process. Hand films and skin biopsies showed extensive vascular calcification, and a computerized tomography scan confirmed colonic perforation and disseminated visceral vascular calcification. Histologic analysis of the resected skin and colonic tissues revealed extensive ischemic damage and mural calcification of medium to large vessels. Gastrointestinal involvement has been reported in only 3 prior cases of calciphylaxis; consequently, gastroenterologists are often unaware of this disease entity and may fail to recognize it, even in patients with the classical presention. Prompt diagnosis is crucial, as parathyroidectomy may result in clinical improvement in up to two thirds of patients who present with elevated parathyroid hormone levels.

Background & Aims:: Integrins (@a"4 and @b"2) and their endothelial ligands vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) play key roles in leukocyte recruitment to areas of inflammation. ICAM-1 and VCAM-1 are expressed in inflamed intestinal tissues. This study investigates a possible causative role of adhesion molecules ICAM-1, VCAM-1, and @a"4 integrins in mediating the inflammatory response in a murine model of Crohn's disease (CD). Methods:: CD4^+ mesenteric lymph node cells from SAMP-1/Yit donor mice were adoptively transferred into major histocompatibility complex-matched severe combined immunodeficiency disease mice. Six weeks later, these mice were left untreated or treated for 3 days with monoclonal antibodies (mAbs) to ICAM-1, VCAM-1, or both, and @a"4, or both ICAM-1 and @a"4, dexamethasone, or nonblocking isotype control antibodies. On day 4 after treatment, tissues were investigated for expression of ICAM-1, VCAM-1, and for severity of inflammation using a semiquantitative inflammatory score. Dexamethasone treatment resolved all measures of intestinal inflammation. Results:: Blocking either ICAM-1, VCAM-1, or @a"4 integrins had no significant beneficial effect. However, blocking ICAM-1 and @a"4, or blocking ICAM-1 and VCAM-1, showed a 70% resolution of the active inflammation, but not chronic inflammation. Conclusions:: These findings suggest that blocking ICAM-1 and VCAM-1 may have therapeutic benefit for the acute inflammatory component of Crohn's disease.

Reaction of Ru₃(CO)₁₂ and S(C&z.tbd;CSiMe₃)₂ in toluene gave [Ru₃(CO)₉(μ-η2-SC&z.tbd;CSiMe₃)(μ₃-η2-C&z.tbd;CSiMe₃)] 1. The thermolysis of 1 provokes the rupture of the S–C_sp bond of the SC&z.tbd;CSiMe₃ ligand and C–C coupling reactions between two acetylide groups affording the clusters [Ru₃(CO)₉(μ₃-S)(μ₃-η2-C(SiMe₃)C(C&z.tbd;CSiMe₃)] 2, [Ru₂(CO)₆(μ-η3-SC&z.tbd;CSiMe₃)(μ-η2-C&z.tbd;CSiMe₃)] 3, [Ru₄(CO)₁₂(μ₄-S)(μ-η2-C&z.tbd;CSiMe₃)₂] 4 and [Ru₄(CO)₉(μ-CO)₂(μ₄-S)(μ₄-η2-C(SiMe₃)C(C&z.tbd;CSiMe₃)] 5. All compounds have been characterized by IR and NMR techniques as well as FAB+ mass spectrometry. Crystal structures of 1, 4, and 5 have been determined by X-ray diffraction methods. The pathways of the thermolysis of 1 to give 2–5 have been investigated.

In this talk we briefly describe some basic elements of chiral perturbation theory, xPT, and how the implementation of unitarity and other novel elements lead to a better expansion of the T-matrix for meson-meson and meson-baryon interactions. Applications are then done to the ππ interaction in nuclear matter in the scalar and vector channels, antikaons in nuclei and K−atoms, and how the φ meson properties are changed in a nuclear medium.

Our best pharmacologic agents for osteoporosis treatment prevent no more than 40‐60% of osteoporotic fractures in patients at highest risk. Thus, there is a need for agents that can further augment bone mass and reduce fracture risk more substantially. To this end, we investigated the utility of parathyroid hormone (PTH) in combination with established hormone‐replacement therapy (HRT) in women with osteoporosis. Fifty‐two women who had been on HRT for at least 2 years were enrolled in this trial in which 25 were assigned randomly to remain on HRT alone and 27 were assigned to remain on HRT and also receive daily subcutaneous PTH(1‐34) 400 U (25 μg) per day for 3 years. Bone mineral density (BMD) measurements at the spine, hip, and total body as well as biochemical determinations of bone turnover and calcium homeostasis were obtained every 6 months. Lateral thoracic and lumbar spine X‐rays were obtained at baseline and annually. Subjects also had measurements of bone density and biochemical indices of bone turnover 1 year after discontinuation of PTH, while HRT was continued. In the group receiving HRT alone, bone density and biochemical variables of bone turnover remained stable throughout the 3‐year treatment trial and 1‐year follow‐up. In the PTH + HRT group, biochemical variables of bone formation and resorption peaked at 6 months and subsequently remained elevated until 30 months at which time levels were indistinguishable from baseline. Subjects in the PTH + HRT group increased bone mass by 13.4 ± 1.4% in the spine, 4.4 ± 1.0% in the total hip, and 3.7 ± 1.4% in the total body. Bone density measurements remained stable 1 year after discontinuation of PTH without any significant loss while women continued HRT. Biochemical variables did not change significantly after cessation of PTH through the 1‐year follow‐up period. PTH + HRT reduced the percent of women who had vertebral fractures from 37.5% to 8.3% (using a 15% height reduction criterion) and from 25% to 0% (using a 20% height reduction criterion) compared with women receiving HRT alone (p< 0.02 for both). We conclude that ongoing HRT maintains almost all of the PTH‐induced bone mass increment for 1 year after discontinuation of PTH. Furthermore, PTH in combination with hormone therapy is an effective means of increasing bone mass throughout the skeleton and specifically reducing vertebral fracture occurrence by 75‐100%, compared with HRT alone.

We have measured the chromatic‐discrimination ellipses with different luminances for 66 stimuli distributed throughout the CIE‐1931 chromatic diagram. The distribution of these stimuli enabled us to analyze the influence of luminance on discrimination from clearly photopic levels to levels that could enter the mesopic range. The results show a clear influence of the luminance level on the areas of the chromatic‐discrimination ellipses. These areas remain almost constant when the luminance level is clearly photopic, and clearly increase when the luminance diminishes. However, it is not necessary that the luminance level diminish far below 2–3 cd/m2to detect a substantial increase in the area of the ellipses. According to our data, within the photopic range appears a transition interval of luminance above which the most pronounced increase in the area of the ellipse would be appreciable. Other parameters characteristic of discrimination ellipses, such as orientation and relation to semi‐axes, vary with the luminance level, although without clearly following any rule. © 2001 John Wiley & Sons, Inc. Col Res Appl, 26, 123–131, 2001

Abstract: Using the analysis of ChPT to two loops, we perform an error analysis of the threshold and low-energy parameters, based on the uncertainties for the one-loop low-energy parameters and the resonance saturation mechanism. Different sets of one-loop low-energy constants have been considered. Thus, the predictive power of the effective field theory, is quantified on the basis of the present experimental uncertainties.

The imido−amido complex [TaCp*(N^tBu)Cl(NH^tBu)], 1, was isolated from the reaction of [TaCp*Cl4] with 3 equiv of LiNH^tBu. The dimethyl [TaCp*(N^tBu)Me2], 2, and chloro−methyl [TaCp*(N^tBu)ClMe], 3, complexes were obtained by methylation of [TaCp*(N^tBu)Cl2] with 2 equiv of LiMe and 1 equiv of ZnMe2, respectively. Metathetical reactions of complex 3 with alkali metal salts MX (M = Na, X = OMe; M = Li, X = O^tBu, NH^tBu) afforded the new imido−methyl compounds [TaCp*(N^tBu)MeX] (X = OMe 4, O^tBu 5, NH^tBu 6). Insertion of CNR (R = 2,6-Me2C6H3) into the Ta−NH^tBu and Ta−Me bonds of the imido−pentamethylcyclopentadienyl complexes 1−6 gave the η²-iminocarbamoyl compound [TaCp*(N^tBu)Cl{η²-C(NH^tBu)&dbd;NR}], 7, and the η²-iminoacyl compounds [TaCp*(N^tBu)X{η²-C(Me)&dbd;NR}] (X = Me 8, Cl 9, OMe 10, O^tBu 11, NH^tBu 12), which under appropriate thermal conditions react with a second equivalent of CNR (R = 2,6-Me2C6H3) to give the double insertion imine−η²-iminoacyl products [TaCp*(N^tBu)X{η²-C[C(Me)&dbd;NR]&dbd;NR}] (X = Me 13, Cl 14, OMe 15, O^tBu 16, NH^tBu 17). When compound 17 was heated at 140 °C for 3 days, an intramolecular proton migration occurred to give the η²-diamidoalkene complex [TaCp*(N^tBu){η-N^tBu-C(NHR)&dbd;C(Me)-η-NR}], 18. All of the new compounds were characterized by IR, ¹H NMR, and ¹³C NMR spectroscopy, and the molecular structures of 14 and 18 were studied by X-ray diffraction methods.