To combat infections on biomedical devices, antimicrobial coatings have attracted considerable attention, including coatings comprising naturally occurring antimicrobial peptides (AMPs). In this study the aim was to explore performance upon extended challenge by bacteria growing in media above samples. The AMPs LL37, Magainin 2, and Parasin 1 were covalently grafted onto a plasma polymer platform, which enables application of this multilayer coating strategy to a wide range of biomaterials. Detailed surface analyses were performed to verify the intended outcomes of the coating sequence. Samples were challenged by incubation in bacterial growth media for 5 and 20 hrs. Compared with the control plasma polymer surface, all three grafted AMP coatings showed considerable reductions in bacterial colonization even at the high bacterial challenge of initial seeding at 1x107 CFU, but there were increasing numbers of dead bacteria attached to the surface. All three grafted AMP coatings were found to be non-toxic to primary fibroblasts. These coatings thus could be useful to produce antibacterial surface coatings for biomaterials, though possible consequences arising from the presence of dead bacteria need to be studied further, and compared to non-fouling coatings that avoid attached dead bacteria.

Viral infections, such as those caused by Herpes Simplex Virus-1 (HSV-1) and SARS-CoV-2, affect millions of people each year. However, there are few antiviral drugs that can effectively treat these infections. The standard approach in the development of antiviral drugs involves the identification of a unique viral target, followed by the design of an agent that addresses that target. Antimicrobial peptides (AMPs) represent a novel source of potential antiviral drugs. AMPs have been shown to inactivate numerous different enveloped viruses through the disruption of their viral envelopes. However, the clinical development of AMPs as antimicrobial therapeutics has been hampered by a number of factors, especially their structure as peptides. We have examined the antiviral potential of peptoid mimics of AMPs (sequence-specific N-substituted glycine oligomers). These peptoids have the distinct advantage of being insensitive to proteases, and also exhibit increased bioavailability and stability. Our results demonstrate that several peptoids exhibit potent in vitro antiviral activity against both HSV-1 and SARS-CoV-2 when incubated prior to infection. Visualization by cryo-EM shows viral envelope disruption similar to what has been observed with AMP activity against other viruses. This suggests a common or biomimetic mechanism, possibly due to the differences between the phospholipid head group makeup of viral envelopes and host cell membranes. Furthermore, we observed no cytotoxicity against primary cultures of oral epithelial cells, thus underscoring the potential of this class of molecules as safe and effective broad-spectrum antiviral agents.

Objective: The pleiotropic effect of hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) is responsible for potent defense against inflammatory response. This study evaluated the inhibitory effects of HMG-CoA reductase inhibitors on monosodium urate (MSU)-induced inflammatory response through the regulation of interleukin-37 (IL-37) expression. Methods: Serum was collected from patients with gout (n = 40) and from healthy controls (n = 30). The mRNA and protein expression of target molecules IL-1b, IL-37, caspase-1, and Smad3 was measured in THP-1 cells stimulated with MSU, atorvastatin, or rosuvastatin using real-time quantitative polymerase chain reaction and Western blot assay. Transfection with IL-1b or Smad3 siRNA in THP-1 cells was used to verify the pharmaceutical effect of statins in uric acid-induced inflammation. Results: Serum IL-37 level in gout patients was significantly higher than in controls (p < 0.001) and was associated with serum uric acid level (r = 0.382, p = 0.008). THP-1 cells stimulated with MSU markedly induced IL-37 mRNA expression and transition of IL-37 from cytoplasm to nucleus. Recombinant IL-37 treatment dose-dependently inhibited activation of caspase-1 and IL-1b in MSU-induced inflammation. Atorvastatin and rosuvastatin attenuated caspase-1 activation and mature IL-1b expression but augmented translocation of IL-37 from cytoplasm to nucleus. Atorvastatin and rosuvastatin induced phosphorylation of Smad3 in THP-1 cells treated with MSU crystals. Statins potently attenuated translocation of IL-37 from cytoplasm to nucleus in THP-1 cells transfected with Smad3 siRNA compared to cells with negative control siRNA. Conclusion: This study revealed that statins inhibit MSU-induced inflammatory response through augmentation of phosphorylated Smad3-mediated IL-37 expression in THP-1 cells.

The diet and feeding behavior of South Polar Skuas (Stercorarius maccormicki) are well studied within the species' breeding range, but are poorly understood on the Haswell Islands. Goal: to establish how South Polar Skuas used the abundance of living resources of the Haswell Archipelago (66°31' S, 93°01' E, Davis Sea, Southern Ocean) under conditions of prolonged human activity. Methods: direct observations, study of pellets, spontaneous regurgitation and stomach contents of feathered birds. South Polar Skuas fed primarily on terrestrial resources. The dominant prey of skuas were vertebrates. Emperor Penguins (Aptenodytes forsteri) and Adélie Penguins (Pygoscelis adeliae) make up the bulk of the skuas’ diet in the pre-breeding and breeding periods. Surface feeding at sea was observed in the post-breeding period, when the availability of land-based food resources was reduced. Throughout history, kitchen waste supported the skuas population. Scavenging is the dominant strategy for obtaining food. Predation (primarily on Adélie Penguin eggs and chicks) is of minor importance. South Polar Skuas do not affect the breeding success of Emperor Penguins if they feed on frozen chicks and eggs in their colony. Skua predation influences breeding success of Adélie Penguins and fulmarine petrels, but the extent of the impact is unknown.

Psoriasis (PS) is an autoimmune skin disease mediated by immune cells that typically presents inflammatory erythematous plaques, and it is associated with many comorbidities. PS exhibits excessive keratinocyte proliferation, and a high number of immune cells including macrophages, neutrophils, Th1 and Th17 lymphocytes, and mast cells (MCs). MCs are of hematopoietic origin, derived from bone marrow cells, which migrate, mature and reside in vascularized tissues. They can be activated by antigen provoking overexpression of pro-inflammatory cytokines and release a number of mediators including interleukin (IL)-1 and IL-33. IL-1, released by activated keratinocytes and MCs, stimulates skin macrophage to release IL-36, a powerful pro-inflammatory IL-1 family member. IL-36 mediates both innate and adaptive immunity, including chronic pro-inflammatory diseases such as psoriasis. Suppressing IL-36 results in a noticeable improvement in the treatment of psoriasis. IL-36 is inhibited by IL-36Ra which binds on to IL-36 receptor ligand, but suppression can also occur by binding IL-38 to the IL-36R receptor. IL-38 specifically binds only to IL-36R and inhibits human mononuclear cells stimulated with IL-36 in vitro, sharing the effect with IL-36Ra. Here, we report that inflammation in psoriasis is mediated by IL-1 generated by MCs, a process that activates macrophages to secrete pro-inflammatory IL-36 inhibited by IL-38. In this article we confirm that IL-38 and IL-37 cytokines emerge as inhibitors of inflammation in psoriasis and hold promise of an innovative therapeutic tool.

The structure of self-reinforced composites (SRCs) based on ultra-high molecular weight 21 polyethylene (UHMWPE) was studied by means of Wide-Angle X-Ray Scattering (WAXS), X-Ray 22 tomography, Raman spectroscopy, Scanning Electron Microscopy (SEM) and in situ tensile testing 23 in combination with advanced processing tools like Avizo, ImageJ, and Ncorr to determine the cor-24 relation between the processing conditions, on the one hand, and the molecular structure and 25 mechanical properties, on the other. SRCs were fabricated by hot compaction of UHMWPE fibers at 26 different pressure and temperature combinations without addition of polymer matrix or softener. 27 It was found by WAXS that higher compaction temperatures led to more extensive melting of 28 fibers with the corresponding reduction of the Herman’s factor reflecting the degree of molecular 29 orientation, while the increase of hot compaction pressure suppressed the melting of fibers within 30 SRCs at a given temperature. X-Ray tomography proved the absence of porosity while polarized 31 light Raman spectroscopy measurements for both longitudinal and perpendicular fiber orienta-32 tions showed qualitatively the anisotropy of SRC samples. SEM revealed that the matrix was 33 formed by interlayers of molten polymer entrapped between fibers in SRCs. Moreover, in situ 34 tensile tests demonstrated the increase of Young’s modulus and tensile strength with increasing 35 temperature.

Tumor cells exhibit a resistance-associated secretory phenotype involving extracellular vesicles (EVs) and heat shock proteins (HSPs). This response occurs in response to cell stress and cancer therapeutics. HSPs are stress-responsive molecular chaperones promoting proper protein folding, while also being released from cells with EVs as well as in free form as alarmins. We have here investigated the secretory phenotype of castration-resistant prostate cancer (CRPC) cells using proteome analysis. We have also examined the roles of the key co-chaperone CDC37 in stressome release, epithelial-to-mesenchymal transition (EMT), and tumor progression. A number of HSP family members and their common receptor CD91/LRP1 were enriched at high levels in CRPC cell-derived EVs among over 700 other protein species. The small EVs (30 to 200 nm in size, potentially exosomes) were released even in a non-heated condition from the prostate cancer cells, whereas EMT-coupled release of EVs (200 to 500 nm, likely ectosomes) with associated HSP90α was increased after heat shock stress (HSS). Lactate dehydrogenase, a marker of membrane leakage/damage of cells, was also released upon HSS from the prostate cancer cells. During this stress response, intracellular CDC37 was also transcriptionally inducible by heat shock factor 1, and knockdown of CDC37 decreased EMT-coupled release of EVs. Triple knockdown of CDC37, HSP90α, and HSP90β was required for efficient reduction of the chaperone trio and to reduce tumorigenicity of the CRPC cells in vivo. Taken together, the data indicated that CDC37 and HSP90 are essential for stressome release and for tumorigenesis in resistant cancer.