ABSTRACT
The near-Earth asteroid (162173) Ryugu is a 900-m-diameter dark object expected to contain primordial material from the solar nebula. The Mobile Asteroid Surface Scout (MASCOT) landed on Ryugu's surface on 3 October 2018. We present images from the MASCOT camera (MASCam) taken during the descent and while on the surface. The surface is covered by decimeter- to meter-sized rocks, with no deposits of fine-grained material. Rocks appear either bright, with smooth faces and sharp edges, or dark, with a cauliflower-like, crumbly surface. Close-up images of a rock of the latter type reveal a dark matrix with small, bright, spectrally different inclusions, implying that it did not experience extensive aqueous alteration. The inclusions appear similar to those in carbonaceous chondrite meteorites.
Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Glycopeptides , Anti-Bacterial Agents/pharmacology , Chemical Phenomena , Chemistry, Physical , Dimerization , Magnetic Resonance Spectroscopy , Methicillin Resistance , Molecular Structure , Staphylococcus aureus/drug effects , Vancomycin ResistanceABSTRACT
Previous studies showed that some lactones have beta-lactamase inhibitory or antibacterial effects, others--like A-factor (a gamma-butyrolactone) and its derivatives--stimulate sporulation in Streptomyces griseus strains. Our experiments were aimed at exploring whether synthetic gamma-lactones had such effects. None of the seven gamma-lactones studied showed antibacterial activity, but two of them inhibited beta-lactamases isolated from various bacteria. These two gamma-lactones did not reduce colony formation of murine bone marrow cells in vitro, indicating that they were not toxic to proliferating mammalian cells. Four gamma-lactones, including the two inhibiting beta-lactamase, stimulated sporulation in the non-sporulating S. griseus bald 7 mutant. Further studies of gamma-lactones as potential inhibitors of beta-lactamase seem to be warranted.
Subject(s)
Bone Marrow Cells/drug effects , Lactones/pharmacology , Streptomyces griseus/drug effects , beta-Lactamase Inhibitors , Animals , Anti-Bacterial Agents/pharmacology , Bone Marrow Cells/cytology , Cell Division/drug effects , Colony-Forming Units Assay , Dose-Response Relationship, Drug , Lactones/chemical synthesis , Lactones/chemistry , Mice , Microbial Sensitivity Tests , Spores, Bacterial/drug effects , beta-Lactams/pharmacologyABSTRACT
Acylation of amoxycillin and cephalexin with acids III, V and VII, and with isocyanate VIII furnished the corresponding beta-lactam antibiotics (X and XIII-XV, respectively). The antibacterial activity of these new antibiotic analogues against Helicobacter pylori was found to be identical with those of amoxycillin, Augmentin, erythromycin and ciprofloxacin.
Subject(s)
Amoxicillin/analogs & derivatives , Anti-Bacterial Agents/chemical synthesis , Cephalexin/analogs & derivatives , Acylation , Amoxicillin/chemical synthesis , Amoxicillin/pharmacology , Anti-Bacterial Agents/pharmacology , Cephalexin/chemical synthesis , Cephalexin/pharmacology , Drug Design , Helicobacter pylori/drug effects , Microbial Sensitivity Tests , Organophosphonates , Staphylococcus aureus/drug effectsABSTRACT
The cell distribution and function of alveolar macrophages and T lymphocytes were investigated in the bronchoalveolar lavage (BAL) of 15 patients with systemic sclerosis (SSc). In alveolar macrophages, both spontaneous and PMA-stimulated TNF-alpha production were increased in SSc. PMA-induced IL-6 production was also elevated. Spontaneous IL-6 excretion of scleroderma alveolar macrophages was similar to the controls. Yeast and C3b-coated yeast (opsonised yeast) phagocytosis, chemotaxis and Fc receptor activity of alveolar macrophages were normal. The proportion of CD3, CD4 and CD8 T-lymphocyte subsets in the BAL was similar to the control values. The lymphocyte blast transformation index of the non-adherent cells deriving from the BAL fluid was markedly decreased.