A Novel Platelet Activating Factor Receptor Antagonist Reduces Cell Infiltration and Expression of Inflammatory Mediators in Mice Exposed to Desiccating Conditions after PRK

Purpose. To study the contribution of a novel PAF receptor antagonist LAU-0901 in the modulation of the increased inflammatory response in mice exposed to dessicating conditions (DE) after PRK. Methods. Eighty 13-14 week old female Balb/C mice were used. They were divided into two groups: One group was treated with LAU-0901 topical drops. The other group was treated with vehicle. In each group ten mice served as controls and ten were placed in DE. The other twenty mice underwent bilateral PRK and were divided in two additional groups: ten mice remained under normal conditions (NC) and the other ten were exposed to DE. After 1 week all animals underwent in vivo confocal microscopy, immunostaining and western blotting analysis. Results. Confocal microscopy showed an increased number of reflective structures in the corneal epithelium after PRK and exposure to DE in eyes treated with vehicle as compared to eyes treated with LAU-090). Significant decrease of COX-2 and Arginase I expression and reduced alpha SMA cells was observed after PRK and exposure to DE in eyes treated with LAU-0901. Discussion: Exposure of mice to a DE after PRK increases the epithelial turnover rate. PAF is involved in the inflammatory cell infiltration and expression of inflammatory cytokines that follow PRK under DE

Pentamethylcyclopentadienyl-dicarbollide derivatives of scandium

The reactions of [Cp*ScCl_2]_x (Cp* = (η^5-C_5Me_5)) with Na_2[C_2B_9H_(11) or [Cp*ScMe_2]_x, with C_2B_9H_(13), followed by treatment with THF yield Cp*(C_2B_9H_(11))Sc(THF)_3. Alkylation of Cp*-(C_2 B_9 H_(11)) with LiCH(SiMe_3)_2 yields Cp(C_2B_9H_(11))ScCH(SiMe_3)_2Li(THF)_3, and {[Cp*(C_2B_9H_(11))ScCH(SiMe_3)_2]_2Li}-Li(THF)_3, which is obtained by its recrystallization from pentane/toluene, has been characterized structurally. This alkyl derivative reacts slowly with H_2 to yield [Cp*(C_2B_9H_(11))SCH]_2[LiTHF)_n]_2, a surprisingly reactive scandium hydride dimer. Once again, recrystallization from toluene affords a crystalline form with less coordinated THF, [Cp*(C_2B_9H_(11))ScH]_2[Li(THF)_2•(3/2)(C_6H_5CH_)3, whose structure reveals that the two anionic [Cp*(C_2B_9H_(11))ScH]^- fragments are held together by reciprocal B-H dative bonding from the dicarbollide ligand to the electron deficient scandium. The potential of pentamethylcyclopentadienyl-dicarbollide derivatives of scandium to serve as efficient a olefin polymerization catalysts is discussed

Two-Dimensional Hydrodynamics of Pre-Core Collapse: Oxygen Shell Burning

By direct hydrodynamic simulation, using the Piecewise Parabolic Method (PPM) code PROMETHEUS, we study the properties of a convective oxygen burning shell in a SN 1987A progenitor star prior to collapse. The convection is too heterogeneous and dynamic to be well approximated by one-dimensional diffusion-like algorithms which have previously been used for this epoch. Qualitatively new phenomena are seen. The simulations are two-dimensional, with good resolution in radius and angle, and use a large (90-degree) slice centered at the equator. The microphysics and the initial model were carefully treated. Many of the qualitative features of previous multi-dimensional simulations of convection are seen, including large kinetic and acoustic energy fluxes, which are not accounted for by mixing length theory. Small but significant amounts of carbon-12 are mixed non-uniformly into the oxygen burning convection zone, resulting in hot spots of nuclear energy production which are more than an order of magnitude more energetic than the oxygen flame itself. Density perturbations (up to 8%) occur at the `edges' of the convective zone and are the result of gravity waves generated by interaction of penetrating flows into the stable region. Perturbations of temperature and electron fraction at the base of the convective zone are of sufficient magnitude to create angular inhomogeneities in explosive nucleosynthesis products, and need to be included in quantitative estimates of yields. Combined with the plume-like velocity structure arising from convection, the perturbations will contribute to the mixing of nickel-56 throughout supernovae envelopes. Runs of different resolution, and angular extent, were performed to test the robustness of theseComment: For mpeg movies of these simulations, see http://www.astrophysics.arizona.edu/movies.html Submitted to the Astrophysical Journa

A tribenzylidenemethane–tantalum compound: some experiences with 'inversion twinning'

The six-electron-donating ligand tribenzylidenemethandiide has been used to form a tantalum (group 5) mimic, (η^5-cyclopentadienyl)(η^4-tribenzylidenemethandiide)dimethyltantalum, of a group 4 bent metallocene. The material crystallizes with two molecules in the asymmetric unit with quite different packing arrangements, although the overall structures of the two are similar. The Cp and methyl ligands are disordered about a threefold axis. Crystal data: [Ta{(C_7H_6)_3C}(C_5H_5)(CH_3), trigonal P31c, with a = 12.681 (3), c = 16.124 (5) Å, V = 2245.5 (7) Å^3, T = 293 K, Z = 4, M_r = 558.47, D_x = 1.65 g cm^(-3), F(000) = 1104, Mo Kα, λ = 0.71073 Å, µ = 4.91 mm^(-1), R = 0.020 for 1319 reflections with F_o > 4σ(F_o); S = 2.18. Because of crystal decay, three separate crystals were needed for a full data set. These polar (but achiral) crystals showed apparently differing amounts of inversion twinning, leading to problems in accurately merging the three data sets and refining the structure. These problems are discussed briefly

Do ultrafast exciton-polaron decoherence dynamics govern photocarrier generation efficiencies in polymer solar cells?

All-organic-based photovoltaic solar cells have attracted considerable attention because of their low-cost processing and short energy payback time. In such systems the primary dissociation of an optical excitation into a pair of photocarriers has been recently shown to be extremely rapid and efficient, but the physical reason for this remains unclear. Here, two-dimensional photocurrent excitation spectroscopy, a novel non-linear optical spectroscopy, is used to probe the ultrafast coherent decay of photoexcitations into charge-producing states in a polymer:fullerene based solar cell. The two-dimensional photocurrent spectra are interpreted by introducing a theoretical model for the description of the coupling of the electronic states of the system to an external environment and to the applied laser fields. The experimental data show no cross-peaks in the two-dimensional photocurrent spectra, as predicted by the model for coherence times between the exciton and the photocurrent producing states of 20\,fs or less

Present and future of surface-enhanced Raman scattering

The discovery of the enhancement of Raman scattering by molecules adsorbed on nanostructured metal surfaces is a landmark in the history of spectroscopic and analytical techniques. Significant experimental and theoretical effort has been directed toward understanding the surface-enhanced Raman scattering (SERS) effect and demonstrating its potential in various types of ultrasensitive sensing applications in a wide variety of fields. In the 45 years since its discovery, SERS has blossomed into a rich area of research and technology, but additional efforts are still needed before it can be routinely used analytically and in commercial products. In this Review, prominent authors from around the world joined together to summarize the state of the art in understanding and using SERS and to predict what can be expected in the near future in terms of research, applications, and technological development. This Review is dedicated to SERS pioneer and our coauthor, the late Prof. Richard Van Duyne, whom we lost during the preparation of this article

ENVIRONMENTAL QUALITY OF SOFT-BOTTOM IN HAIFA BAY (ISRAEL): AMPHIPOD ASSEMBLAGES

Ecological information concerning amphipods and representation of their spatial distribution through GIS provides an estimate of local environmental quality

Expression of angiogenic regulators, VEGF and leptin, is regulated by the EGF/PI3K/STAT3 pathway in colorectal cancer cells.

Abstract Both leptin and vascular endothelial growth factor (VEGF) are growth and angiogenic cytokines that are upregulated in different types of cancer and have been implicated in neoplastic progression. Here we investigated the molecular mechanism by which leptin and VEGF expression are regulated in colon cancer by epidermal growth factor (EGF). In colon cancer cell line HT-29, EGF induced the binding of signal transducer and activator transcription 3 (STAT3) to STAT3 consensus motifs within the VEGF and leptin promoters and stimulated leptin and VEGF mRNA and protein synthesis. All these EGF effects were significantly blocked when HT-29 cells were treated with an inhibitor of the phosphoinositide 3-kinase (PI3K) pathway, LY294002, or with small interfering RNA (siRNA) targeting STAT3. Thus, our study identified the EGF/PI3K/STAT3 signaling as an essential pathway regulating VEGF and leptin expression in EGF-responsive colon cancer cells. This suggests that STAT3 pathways might constitute attractive pharmaceutical targets in colon cancer patients where anti-EGF receptor drugs are ineffective

Recurrent Perineal Hernia After Benign Pelvic Reconstructive Surgery

Abstract Background: Secondary acquired perineal hernias are rare events usually associated with extensive pelvic surgery. Although most are asymptomatic, when symptoms are present surgical intervention is warranted. There is currently no consensus regarding the management of these hernias. An unusual case of a recurrent perineal hernia following sacrospinous fixation resulting in large bowel incarceration is reported. Case: A 64-year-old woman presented with an anterior vaginal wall prolapse and multiple pelvic-floor defects. She subsequently underwent a sacrospinous fixation and enterocele repair. The enterocele recurred and she underwent a second enterocele repair. Approximately 6 months later, she presented with a perineal hernia that involved an incarceration of the large bowel. Results: The hernia was reduced, the pelvic-floor defect was repaired, and a biologic, absorbable mesh was applied. Approximately 5 months later, the patient presented with a recurrence of the perineal hernia. The hernia was reduced and this time a synthetic, nonabsorbable mesh was used, and there were no signs of recurrence at 6 months' follow-up. Conclusions: Acquired perineal hernias are extremely rare events, especially when they recur and involve large bowel incarceration. Several factors may influence the development and possible recurrence of secondary acquired perineal hernias, including lifestyle, occupation, gestational history, and past medical and surgical history. The use of a nonabsorbable mesh to prevent recurrence is suggested, although current literature reports success rates that are fairly similar for users of both absorbable and nonabsorbable meshes. (J GYNECOL SURG 28:230)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98451/1/gyn%2E2011%2E0051.pd

Congenital infiltrating lipoma of the upper limb in a patient with von Willebrand disease

Infiltrating lipoma is a rare variety of lipoma, characterized by an infiltration of the adipose tissue of the muscles. Infiltrating lipomas are usually classified in two groups: intermuscular infiltrating lipoma and intramuscular infiltrating lipoma. Most are acquired, and they usually appear in middle-aged individuals. Exceptionally, they are congenital. In such cases they are not related to other diseases. We report an 8-year-old boy with a congenital infiltrating lipoma of the upper limb and von Willebrand disease. Both diseases are linked to an alteration in chromosome 12, but this clinical association seems to be random rather than causal