426 research outputs found

    Treatment of giant congenital melanocytic nevi with cultured epithelial autografts: Clinical and histopathological analysis

    Get PDF
    [Introduction] Curettage and dermabrasion are effective in the treatment of giant congenital melanocytic nevi (GCMN); however, local infection and hypertrophic scar formation are major issues. Thus, we applied cultured epithelial autografts (CEA) on skin defects after curettage or abrasion of GCMN and assessed the postoperative outcomes. [Methods] Seven nevi lesions of five patients (aged 3 months to 24 years) were treated with CEA after curettage or abrasion with a dermatome or a surgical bar, respectively. We assessed the postoperative outcomes, including CEA take ratio, erosion and/or ulcer formation in the acute phase, hospitalization days, Vancouver scar scale, and color improvement one year after the operation. In addition, a histological evaluation of a skin biopsy was performed over one year after the operation. [Results] The CEAs took well on the wound, and the wound surface was mostly epithelized by postoperative day 7 in all cases. While hypertrophic scar formation and slight pigmentation were observed in some lesions, the color was improved in all of the treated lesions. Histopathological examination revealed that the regenerated epidermis had stratified keratinocytes with rete ridges, and the dermal layer without nevus cells regenerated above the remaining dermis layer. [Conclusions] In this study, we found that early epithelialization and regeneration of the dermal layer was achieved after the application of CEA, suggesting that CEA could be an effective option after curettage or abrasion of GCMN

    A Versatile cascade of intramolecular vilsmeier-haack and azomethine ylide 1,3-dipolar cycloaddition toward tricyclic cores of alkaloids

    Get PDF
    Abstract: In the pursuit of synthetic efficiency, we developed an innovative one-pot transformation of linear substrates into bi- and tricyclic adducts using a cascade of amide activation, nucleophilic cyclization, azomethine ylide generation, and subsequent inter- or intramolecular 1,3-dipolar cycloaddition. Despite the high density and variety of functional groups on the substrates, the sequence occurred with perfect chemoselectivity with good to excellent yields

    2-[3-(Methyl­diphenyl­silyl)prop­yl]isoindoline-1,3-dione

    Get PDF
    In the title compound, C24H23NO2Si, the dihedral angle between the planes of the phenyl rings attached to the Si atom is 80.78 (10)°. In the crystal, the mol­ecules form sheets lying perpendicular to [101] via C—H⋯O inter­actions. These sheets are stacked and linked in a three-dimensional framework by additional C—H⋯O inter­actions in the [10] direction

    GMCs and their Type classification in M74: Toward understanding star formation and cloud evolution

    Full text link
    We investigated the giant molecular clouds (GMCs) in M74 (NGC 628) obtained by the PHANGS project. We applied the GMC Types according to the activity of star formation: Type I without star formation, Type II with Hα\alpha luminosity (LHαL_{\mathrm{H\alpha}}) smaller than 1037.5erg s110^{37.5} \mathrm{erg~s^{-1}}, and Type III with LHαL_{\mathrm{H\alpha}} greater than 1037.5erg s110^{37.5} \mathrm{erg~s^{-1}}. In total, 432 GMCs were identified, where the individual GMC Types are 65, 203, and 164, for Type I, Type II, and Type III, respectively. The size and mass of the GMCs range from 23 - 237 pc and 104.910^{4.9} - 107.110^{7.1} M_{\odot}, showing a trend that mass and radius increase from Type I to II to III. Clusters younger than 4 Myr and HII regions are found to be concentrated within 150 pc of a GMC, indicating a tight association of these young objects with the GMCs. The virial ratio tends to decrease from Type I to III, indicating that Type III GMCs are most relaxed gravitationally among the three. We interpret that GMCs evolve from Type I to III, as previously found in the LMC. The evolutionary timescales of the three Types are estimated to be 2 Myr, 6 Myr, and 4 Myr, respectively, on a steady state assumption, where we assume the timescale of Type III is equal to the age of the associated clusters, indicating a GMC lifetime of 12 Myr or longer. Chevance et al. (2020) investigated GMCs using the same PHANGS dataset of M74, while these authors did not define a GMC, reaching an evolutionary picture with a 20 Myr duration of the non-star forming phase, five times longer than 4 Myr. We compare the present results with those by Chevance et al. (2020) and argue that defining individual GMCs is essential to understanding GMC evolution.Comment: 33 pages, 17 figures, 5 tables

    2-{[(4-Methoxy­phen­yl)dimethyl­silyl]meth­yl}isoindoline-1,3-dione

    Get PDF
    In the course of our studies of silicon-containing anti­cancer compounds, the title compound, C18H19NO3Si, was synthesized. The mol­ecular geometry including bond distances and angles involving the Si atoms are typical. Torsion angles associated with the isoindoline ring and the silyl group [C—N—Cmethyl­ene—Si = 90.5 (2) and −93.1 (2)°] indicate that there is no inter­action between the O and Si atoms despite silicon’s high affinity for oxygen

    Associated molecular and atomic clouds with X-ray shell of superbubble 30 Doradus C in the LMC

    Full text link
    30 Doradus C is a superbubble which emits the brightest nonthermal X- and TeV gamma-rays in the Local Group. In order to explore detailed connection between the high energy radiation and the interstellar medium, we have carried out new CO and HI observations using the Atacama Large Millimeter//Submillimeter Array (ALMA), Atacama Submillimeter Telescope Experiment, and the Australia Telescope Compact Array with resolutions of up to 3 pc. The ALMA data of 12^{12}CO(JJ = 1-0) emission revealed 23 molecular clouds with the typical diameters of \sim6-12 pc and masses of \sim600-10000 MM_{\odot}. The comparison with the X-rays of XMMXMM-NewtonNewton at \sim3 pc resolution shows that X-rays are enhanced toward these clouds. The CO data were combined with the HI to estimate the total interstellar protons. Comparison of the interstellar proton column density and the X-rays revealed that the X-rays are enhanced with the total proton. These are most likely due to the shock-cloud interaction modeled by the magnetohydrodynamical simulations (Inoue et al. 2012, ApJ, 744, 71). Further, we note a trend that the X-ray photon index varies with distance from the center of the high-mass star cluster, suggesting that the cosmic-ray electrons are accelerated by one or multiple supernovae in the cluster. Based on these results we discuss the role of the interstellar medium in cosmic-ray particle acceleration.Comment: 20 pages, 14 figures, 3 tables, accepted for publication in The Astrophysical Journa

    Highly diastereoselective synthesis of substituted pyrrolidines using a sequence of azomethine ylide cycloaddition and nucleophilic cyclization

    Get PDF
    Abstract: Although cycloadditions of azomethine ylides usually give mixtures of endo/exo adducts, we successfully tuned the mechanistic path of a new reaction cascade to afford substituted pyrrolidines in high yields and diastereomeric purity. This was achieved by forcing the demetalation of tin- or silicon-substituted iminium ions, followed by azomethine ylide cycloaddition and nucleophilic cyclization. Structural complexity is thus built rapidly in a fully controlled one-pot reaction cascade
    corecore