RESUMEN
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.
Asunto(s)
Antibacterianos/química , Antibacterianos/síntesis química , Glicopéptidos , Antibacterianos/farmacología , Fenómenos Químicos , Química Física , Dimerización , Espectroscopía de Resonancia Magnética , Resistencia a la Meticilina , Estructura Molecular , Staphylococcus aureus/efectos de los fármacos , Resistencia a la VancomicinaRESUMEN
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.
Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Lactonas/farmacología , Streptomyces griseus/efectos de los fármacos , Inhibidores de beta-Lactamasas , Animales , Antibacterianos/farmacología , Células de la Médula Ósea/citología , División Celular/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Relación Dosis-Respuesta a Droga , Lactonas/síntesis química , Lactonas/química , Ratones , Pruebas de Sensibilidad Microbiana , Esporas Bacterianas/efectos de los fármacos , beta-Lactamas/farmacologíaRESUMEN
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.
Asunto(s)
Amoxicilina/análogos & derivados , Antibacterianos/síntesis química , Cefalexina/análogos & derivados , Acilación , Amoxicilina/síntesis química , Amoxicilina/farmacología , Antibacterianos/farmacología , Cefalexina/síntesis química , Cefalexina/farmacología , Diseño de Fármacos , Helicobacter pylori/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Organofosfonatos , Staphylococcus aureus/efectos de los fármacosRESUMEN
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.
