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Spacecraft magnetic field measurements are able to tell us much about the planets' interior dynamics, composition, and evolutionary timeline. Magnetic fields also serve as the source for passive magnetic sounding of moons. Time‐varying magnetic fields experienced by the moons, due to relative planetary motion, interact electrically with conductive layers within these bodies (including salty subsurface oceans) to produce induced magnetic fields that are measurable by nearby, magnetometer‐equipped spacecraft. Many factors influence the character of the induced field, including the precise amplitude and phase of the time‐varying field, known as the excitation or driving field and represented by excitation moments. In this work, we present an open‐source Matlab software package named PlanetMag that features calculation of planetary magnetic field models available in the literature at arbitrary positions and times. The implemented models enable simultaneous inversion of the excitation moments across a range of oscillation frequencies using linear least‐squares methods and ephemeris data with the SPICE toolkit. Here we summarize the available magnetic field models and their associated coordinate systems. Precisely determined excitation moments are a critical input to forward models of global induced fields. Our results serve as a prerequisite to any precise comparison to spacecraft data for magnetic sounding investigation of giant planet moons—connecting the induced magnetic field to a moon's interior requires accurate representation of the oscillating excitation field. We calculate complex excitation moments relative to the J2000 epoch and share the results as ASCII tables compatible with related software packages intended for induction response calculations. Plain Language Summary: Planetary magnetic fields tell us much about a planet's interior, composition, and history. Magnetic fields are also useful for remotely probing the interior of their moons, especially for finding and characterizing potential subsurface oceans. Liquid‐water oceans within the solar system are ideal places to search for habitable environments beyond Earth. Relating spacecraft magnetic measurements to the interior properties of the moons requires an understanding of various related components, including the manner in which the magnetic field applied to the moon changes with time. We have developed an open‐source software package called PlanetMag that uses published magnetic field models to estimate the magnetic field at any point in time and space. It also has the ability to precisely estimate the planetary field oscillations at the location of each large moon in the solar system, which is needed for prediction of the magnetic field response from the moon. Calculations of these magnetic oscillations are provided in text files compatible with existing software. Key Points: We developed an open‐source software package in Matlab called PlanetMag for evaluating planet magnetic field models from the literaturePlanetMag uses ephemeris data and least‐squares inversion methods to determine amplitudes and phases of magnetic excitations for moonsComplex excitation moments are determined for all outer planet large moons in support of magnetic sounding investigations [ABSTRACT FROM AUTHOR]

The UDP-2,3-diacylglucosamine pyrophosphate hydrolase LpxH is an essential lipid A biosynthetic enzyme that is conserved in the majority of gram-negative bacteria. It has emerged as an attractive novel antibiotic target due to the recent discovery of an LpxH-targeting sulfonyl piperazine compound (referred to as AZ1) by AstraZeneca. However, the molecular details of AZ1 inhibition have remained unresolved, stymieing further development of this class of antibiotics. Here we report the crystal structure of Klebsiella pneumoniae LpxH in complex with AZ1. We show that AZ1 fits snugly into the L-shaped acyl chain-binding chamber of LpxH with its indoline ring situating adjacent to the active site, its sulfonyl group adopting a sharp kink, and its N-CF3-phenyl substituted piperazine group reaching out to the far side of the LpxH acyl chain-binding chamber. Intriguingly, despite the observation of a single AZ1 conformation in the crystal structure, our solution NMR investigation has revealed the presence of a second ligand conformation invisible in the crystalline state. Together, these distinct ligand conformations delineate a cryptic inhibitor envelope that expands the observed footprint of AZ1 in the LpxH-bound crystal structure and enables the design of AZ1 analogs with enhanced potency in enzymatic assays. These designed compounds display striking improvement in antibiotic activity over AZ1 against wild-type K. pneumoniae, and coadministration with outer membrane permeability enhancers profoundly sensitizes Escherichia coli to designed LpxH inhibitors. Remarkably, none of the sulfonyl piperazine compounds occupies the active site of LpxH, foretelling a straightforward path for rapid optimization of this class of antibiotics. [ABSTRACT FROM AUTHOR]

The basic proteins of rat neutrophils possessing the capacity to induce vascular Permeability were analysed. Evidence indicating the presence of four such permeability proteins was presented. One of these induced the release of' histamine from rat mast cells. [ABSTRACT FROM AUTHOR]

Acute renal injury was induced immunologically with sheep antisera to rabbit glomerular basement membrane which were largely dependent on poly- morphonuclcar leucocytes (PMNs) for their pathogenic effect. This injury was characterized by the liberation of glomerular basement membrane material into the urine and a concomitant gross alteration in the permeability of the glomerular basement membrane. Selectivity of proteinuria was extremely low during PMN- mediated injury. These effects were eliminated by PMN depletion prior to the induction of experimental nephritis and were not observed when glomerular injury was induced by an antibody not significantly dependent upon PMNs. Of the known mediators of inflammation contained within PMNs, both acid proteases (cathepsins) and cationic proteins were found in the urines of rabbits with nephritis induced by a PMN-dependent antiserum. [ABSTRACT FROM AUTHOR]

The chemotactic factor, generated in whole rabbit serum following treatment with immune precipitates, was found to be principally associated with fractions containing the fifth and sixth components of complement (C'5 and C'6) after electrophoretic separation of serum. The chemotactic factor could also be generated in the intact animal, adding credence to its importance in tissue reactions induced by immunological agents. The isolated and activated C'5 and C'6 complex was found to be at least 10-20 times more active in the chemotaxis of rabbit polymorphonuclear leucocytes (PMNs) in vitro than bradykinin, kallidin, histamine, serotonin and extracts of PMN granules. The amino acid derivatives N-CBZ-glycyl-L-phenylalanine and N-CBZ-α glutamyl-L-tyrosine inhibited formation of the chemotactic factor in serum. The latter derivative also caused loss of activity of the preformed chemotactic factor in rabbit serum and in density gradient ultracentrifugation it was found that the C'5 and C'6 complex dissociated in the presence of this inhibitor. Chemotactically active C'5 to C'6 fractions, when added to the suspension of PMNs, prevented the ability of these cells to migrate toward a chemotactic source. It was also found that the ratio of combination of C'5 and C'6 was critical for the full expression of chemotactic activity. Utilizing purified components of human C', very recently obtained data indicate the requirement of the seventh component of C' (C'7) for generation of chemotactic activity. No later reacting components of C' are required. Whether C'7 is incorporated into the chemotactically active complex which sediments rapidly in the ultracentrifuge is not yet established. Similar data with guinea-pig C' complexes were also obtained. [ABSTRACT FROM AUTHOR]