Anti-Infective and Anti-Inflammatory Mode of Action of Peptide 19-2.5

The polypeptide Pep19-2.5 (Aspidasept®) has been described to act efficiently against infection-inducing bacteria by binding and neutralizing their most potent toxins, i.e., lipopolysaccharides (LPS) and lipoproteins/peptides (LP), independent of the resistance status of the bacteria. The mode of action was described to consist of a primary Coulomb/polar interaction of the N-terminal region of Pep19-2.5 with the polar region of the toxins followed by a hydrophobic interaction of the C-terminal region of the peptide with the apolar moiety of the toxins. However, clinical development of Aspidasept as an anti-sepsis drug requires an in-depth characterization of the interaction of the peptide with the constituents of the human immune system and with other therapeutically relevant compounds such as antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs). In this contribution, relevant details of primary and secondary pharmacodynamics, off-site targets, and immunogenicity are presented, proving that Pep19-2.5 may be readily applied therapeutically against the deleterious effects of a severe bacterial infection.

The exceptional X-ray evolution of SN 1996cr in high resolution

ABSTRACT We present X-ray spectra spanning 18 yr of evolution for SN 1996cr, one of the five nearest SNe detected in the modern era. Chandra HETG exposures in 2000, 2004, and 2009 allow us to resolve spectrally the velocity profiles of Ne, Mg, Si, S, and Fe emission lines and monitor their evolution as tracers of the ejecta-circumstellar medium interaction. To explain the diversity of X-ray line profiles, we explore several possible geometrical models. Based on the highest signal-to-noise 2009 epoch, we find that a polar geometry with two distinct opening angle configurations and internal obscuration can successfully reproduce all of the observed line profiles. The best-fitting model consists of two plasma components: (1) a mildly absorbed (2 × 1021 cm−2), cooler (≈2 keV) with high Ne, Mg, Si, and S abundances associated with a wide polar interaction region (half-opening angle ≈58°); (2) a moderately absorbed (2 × 1022 cm−2), hotter ($\gtrsim$20 keV) plasma with high Fe abundances and strong internal obscuration associated with a narrow polar interaction region (half-opening angle ≈20°). We extend this model to seven further epochs with lower signal-to-noise ratio and/or lower spectral-resolution between 2000 and 2018, yielding several interesting trends in absorption, flux, geometry, and expansion velocity. We argue that the hotter and colder components are associated with reflected and forward shocks, respectively, at least at later epochs. We discuss the physical implications of our results and plausible explosion scenarios to understand the X-ray data of SN 1996cr.

A Facile Activation Method for Improving the Wettability of Polyurethane Surfaces

This work reports the activation of polyurethane film surfaces in order to enrich them with polar groups such as -NH2, -OH, -COOH or radicals, which further allows immobilization of several bioactive compounds. UV-activation was used to introduce new groups on the polymer surface without affecting the bulk properties. The current arising species improve the wettability of the PU surfaces as it was observed from the static contact angle measurements. The structure and composition of the new PU surfaces were analyzed by using ATR-FTIR spectroscopy. The results suggested the possibility of modifying the PU surfaces in a shorter time periods, in order to provide many sites to attach other biomacromolecules by polar interaction or hydrogen bonding.

The polar localization hub protein PopZ restrains adaptor dependent ClpXP proteolysis inCaulobacter crescentus

ABSTRACTInCaulobacter crescentus, timely degradation of several proteins by the ClpXP protease is critical for proper cell cycle progression. During the cell cycle, the ClpXP protease, the substrate CtrA and many other proteins are localized to the stalked pole dependent on a polar interaction hub composed of PopZ protein oligomers. Prior work suggests that the localization of ClpXP, protease substrates, and cofactors is needed for recognition of substrates such as CtrA by ClpXP. Here, we formally test this hypothesis by examining the role of PopZ in ClpXP activity and find surprisingly that CtrA degradation is enhanced in cells lacking polar localization due to loss of PopZ. The ClpXP adaptor CpdR is required for this enhanced degradation of CtrA and other adaptor-dependent substrates, but adaptor-independent substrate degradation is not affected upon loss of PopZ. We find that overexpression of PopZ also leads to faster degradation of CtrA, but is likely due to nonphysiologically relevant recognition of CtrA by ClpXP alone as loss of CpdR does not affect this enhancement. Our main conclusion is that loss of PopZ, and therefore loss of polar localization, does not result in the loss of ClpXP regulated proteolysis, as would be predicted from a model which requires polar localization of ClpXP for its activation. Rather, our data point to a model where PopZ normally restrains ClpXP proteolysis by promoting the inactivation of the CpdR adaptor, likely through the phosphorylation activity of the CckA kinase.

Micromagnetic Study on the Dynamic Susceptibility Spectra of Square-Patterned Ferromagnets

We have systematically investigated the dynamic susceptibility spectra of square-patterned ferromagnets in the mesoscopic scale from 100 nm to 500 nm by means of a micromagnetic simulation. The dynamic susceptibility spectra are obtained from the magnetization response under the applied field using Fourier transforms technique. We have observed that the frequency peak of the susceptibility spectra slightly increases as the length of the square-patterned increases. Interestingly, the frequency peak shows similar behavior compared to the frequency resonance from Kittel’s formula. We have also analyzed the magnetic energies, where the demagnetization energy is larger than the exchange energy. It can be explained that the polar interaction primarily contributes to the resonance mode of the square-patterned ferromagnets

Effect of Sepiolite Nanofibers on Properties of EPDM Nanocomposites

In order to use sepiolite nanofibers as rubber fillers, the hydrophilic character of sepiolite nanofibers should be modified by grafting organic group and controlling surface energy and proportion of dispersive interaction for improving compatibility of sepiolite nanofibers in rubber matrix. The surface energies of sepiolite nanofibers were measured by several liquids which were different on surface energy and polar interaction and calculated by Wus equation. The results showed that the mechanical properties can be improved after reinforcement by modified sepiolite nanofibers.