Explore the vast range of titles available.

Antimicrobial cationic peptides are of interest because they can combat multi-drug-resistant microbes. Most peptides form α-helices or β-sheet-like structures that can insert into and subsequently disintegrate negatively charged bacterial cell surfaces. Here, we show that a novel class of core–shell nanoparticles formed by self-assembly of an amphiphilic peptide have strong antimicrobial properties against a range of bacteria, yeasts and fungi. The nanoparticles show a high therapeutic index against Staphylococcus aureus infection in mice and are more potent than their unassembled peptide counterparts. Using Staphylococcus aureus -infected meningitis rabbits, we show that the nanoparticles can cross the blood–brain barrier and suppress bacterial growth in infected brains. Taken together, these nanoparticles are promising antimicrobial agents that can be used to treat brain infections and other infectious diseases. A class of core–shell nanoparticles self-assembled from amphiphilic peptides can kill a range of bacteria, yeast and fungus. They are more potent than their unassembled peptide counterparts and can suppress bacterial growth in the brains of rabbits infected with meningitis. These particles, which carry a high number of positive charges, are promising antimicrobial agents.

Indoor mold due to water damage causes serious human respiratory disorders, and the remediation to homes, schools, and businesses is a major expense. Prevention of mold infestation of building materials would reduce health problems and building remediation costs. Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit yeasts and a limited number of filamentous fungi. The purpose of this research was to determine the possible inhibitory activity of nonsteroidal anti-inflammatory drugs (NSAIDs) on germination, fungal growth, and reproduction of Chaetomium globosum and other important filamentous fungi that occur in water-damaged buildings. Several NSAIDs were found to inhibit C. globosum germination, growth, and reproduction. The most effective NSAIDs inhibiting C. globosum were ibuprofen, diflunisal, and diclofenac. Fusarium oxysporum, Fusarium solani, Aspergillus niger, and Stachybotrys atra were also tested on the various media with similar results obtained. However, F. oxysporum and A. niger exhibited a higher level of resistance to aspirin and NaSAL when compared to the C. globosum isolates. The inhibition exhibited by NSAIDs was variable depending on growth media and stage of fungal development. These compounds have a great potential of inhibiting fungal growth on building materials such as gypsum board. Formulations of sprays or building materials with NSAID-like chemical treatments may hold promise in reducing mold in homes and buildings.

The objectives were to determine the influence of water activity (a w , 0.997–0.92) and temperature (10–37°C) and their interactions on conidial germination, mycelial growth and sporulation of two strains of Stachybotrys chartarum in vitro on a potato dextrose medium. Studies were carried out by modifying the medium with glycerol and either spread plating with conidia to evaluate germination and germ tube extension or centrally inoculating treatment media for measuring mycelial growth rates and harvesting whole colonies for determining sporulation. Overall, germination of conidia was significantly influenced by a w and temperature and was fastest at 0.997–0.98 a w between 15 and 30°C with complete germination within 24 h. Germ tube extension was found to be most rapid at similar a w levels and 25–30°C. Mycelial growth rates of both strains were optimal at 0.997 a w between 25 and 30°C, with very little growth at 37°C. Sporulation was optimum at 30°C at 0.997 a w . However, under drier conditions, this was optimum at 25°C. This shows that there are differences in the ranges of a w x temperature for germination and growth and for sporulation. This may help in understanding the role of this fungal species in damp buildings and conditions under which immune-compromised patients may be at risk when exposed to such contaminants in the indoor air environment.

Reducing occupant exposure to indoor mold is the goal of this research, through the efficacy testing of antimicrobial cleaners. Often mold contaminated building materials are not properly removed, but instead surface cleaners are applied in an attempt to alleviate the problem. The efficacy of antimicrobial cleaners to remove, eliminate or control mold growth on surfaces can easily be tested on non-porous surfaces. However, the testing of antimicrobial cleaner efficacy on porous surfaces, such as those found in the indoor environment such as gypsum board can be more complicated and prone to incorrect conclusions regarding residual organisms. The mold Stachybotrys chartarum has been found to be associated with idiopathic pulmonary hemorrhage in infants and has been studied for toxin production and its occurrence in water damaged buildings. Growth of S. chartarum on building materials such as gypsum wallboard has been frequently documented. Research to control S. chartarum growth using 13 separate antimicrobial cleaners on contaminated gypsum wallboard has been performed in laboratory testing. Popular brands of cleaning products were tested by following directions printed on the product packaging. A variety of gypsum wallboard surfaces were used to test these cleaning products at high relative humidity. The results indicate differences in antimicrobial efficacy for the six month period of testing. Results for the six types of GWB surfaces varied extensively. However, three cleaning products exhibited significantly better results than others. Lysol All-Purpose Cleaner-Orange Breeze (full strength) demonstrated results which ranked among the best in five of the six surfaces tested. Both Borax and Orange Glo Multipurpose Degreaser demonstrated results which ranked among the best in four of the six surfaces tested. The best antimicrobial cleaner to choose is often dependent on the type of surface to be cleaned of S. chartarum contamination. For Plain GWB, no paint, the best cleaners were Borax, Lysol All-Purpose Cleaner-Orange Breeze (full strength), Orange Glo Multipurpose Degreaser, and Fantastik Orange Action. These results are not meant to endorse the incomplete removal of mold contaminated building materials. However, it is recognized that complete removal may not always be possible and solutions to control mold regrowth may contribute to reduced occupant exposure. Current recommendations of removal and replacement of porous building materials should be followed. It is not the intension of this discussion to endorse any product. Reporting on the performance of these products under the stated conditions was and remains the only purpose.

Reducing occupant exposure to mold growing on damp gypsum wallboard and controlling mold contamination in the indoor environment was studied through 1) delineation of environmental conditions required to promote and avoid mold growth and 2) efficacy testing of antimicrobial products, specifically cleaners and paints, on gypsum wallboard (GWB) surfaces. The effects of moisture and relative humidity (RH) on mold growth and transport are important in avoiding and eliminating problems. These effects have been demonstrated on GWB and are discussed in this article for use as control guidance. The authors discuss the efficacy of antimicrobial cleaners and paints to remove, eliminate, or control mold growth on GWB. Research to controlStachybotrys chartarumgrowth using 13 separate antimicrobial cleaners and nine varieties of antimicrobial paint on contaminated GWB was performed in laboratory testing. GWB surfaces were subjected to high RH. GWB control measures are summarized and combined, and the antimicrobial product results are explained.

Sections (8 cm2) of unused, nonsterile gypsum wallboard (dry wall) were inoculated with varying densities (10(4) to approximately 10(8)/ml) of conidia from 14- to 21-day cultures of Stachybotrys chartarum grown on cellulose agar. The sections were permitted to air dry and were placed into vessels with 86% or 92% RH and incubated at 22-25 degrees C for up to 12 weeks. The moisture content of the dryboard increased from near 10% to over 35%. Selected sections with confluent surface growth, mainly of S. chartarum, were obtained within 3 weeks. Sections were cleaned with a quaternary or quaternary and chlorine dioxide or a concentrated oxygen-saline solution and treated, in some cases, with a preservative system and returned to humidity vessels. Reemergence of S. chartarum from inoculated and treated surfaces occurred within 5 weeks only with sections treated with the quaternary alone. Other fungi, mostly species of Aspergillus, Chaetomium and Penicillium, slowly colonized (between 9-12 weeks) at least some areas of most treated surfaces and most uninoculated control surfaces. Stachybotrys chartarum was also found on several sections of uninoculated controls. Sections treated with a quaternary/acrylic and placed in a dynamic challenging chamber remained visually free of colonized fungi for over 90 days. These studies indicate that control samples of uninstalled wallboard, available from local distributors, can contain a baseline bioburden, including S. chartarum, that will colonize surfaces under high humidity conditions. Sanitation and preservation treatment of the wallboard can markedly delay regrowth of these fungi, particularly of S. chartarum.

Stachybotrys microspora triprenyl phenol (SMTP) is a large family of small molecules derived from the fungus S. microspora. SMTP acts as a zymogen modulator (specifically, plasminogen modulator) that alters plasminogen conformation to enhance its binding to fibrin and subsequent fibrinolysis. Certain SMTP congeners exert anti-inflammatory effects by targeting soluble epoxide hydrolase. SMTP congeners with both plasminogen modulation activity and anti-inflammatory activity ameliorate various aspects of ischemic stroke in rodents and primates. A remarkable feature of SMTP efficacy is the suppression of hemorrhagic transformation, which is exacerbated by conventional thrombolytic treatments. No drug with such properties has been developed yet, and SMTP would be the first to promote thrombolysis but suppress disease-associated bleeding. On the basis of these findings, one SMTP congener is under clinical study and development. This review summarizes the discovery, mechanism of action, pharmacological activities, and development of SMTP.

In this investigation, the anti-inflammatory potential of phenylspirodrimanes (PSDs) produced by the marine-derived fungal strain Stachybotrys sp. SZU-W23 was systematically explored. A total of 15 PSDs were successfully isolated. Among them, four novel compounds, designated as chartarlactams U-X, were precisely characterized using NMR, HRESIMS, and ECD analyses. Specifically, compound 10 exhibited the most potent inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 macrophages within the 0.3–30 μM concentration range, with an IC50 value of 12.4 μM. Additionally, MTT assays revealed no detectable cytotoxicity at these concentrations. Mechanistic studies revealed that compound 10 effectively suppressed ROS generation, likely inactivating the NF-κB signaling pathway and consequently downregulating pro-inflammatory mediators, including iNOS, IL-6, and IL-1β.

Fungal immunomodulatory protein (FIP)-sch2, an immunomodulatory protein identified in the ascomycete Stachybotrys chlorohalonata by a sequence similarity search, is a novel member of the FIP family. FIP-sch2 shares high sequence identity, structure, and evolutionary conservation with previously reported FIPs. It was satisfactorily expressed in Escherichia coli with a glutathione S-transferase (GST) tag and purified by GST-affinity magnetic beads. To characterize the direct antitumor effects, human lung adenocarcinoma A549 cells were treated with different concentrations of recombinant FIP (rFIP)-sch2 in vitro, and the results showed that rFIP-sch2 could reduce cell viability dose-dependently with a half-maximal inhibitory concentration (IC 50 ) of 9.48 μg/mL. Furthermore, rFIP-sch2 at 8 μg/mL could significantly induce apoptosis and interrupt migration in A549 cells. Notably, the antitumor effect of rFIP-sch2 was equivalent to that of rLZ-8 but was obviously increased compared to rFIP-fve. In addition, the exploration of the antitumor mechanism suggested that rFIP-sch2 induced lung cancer cell death by activating apoptosis and inhibiting migration. Our results indicated that rFIP-sch2 was a promising candidate for use in future cancer therapy.

Stachybotrys ( S .) chartarum is an omnipresent cellulolytic mould which produces secondary metabolites, such as the highly toxic macrocyclic trichothecenes. While it is known to occur in animal feed like hay and straw as well as in water-damaged indoor environments, there is little knowledge about the occurrence of S. chartarum and its secondary metabolites in food. The objective of the present study was to examine selected dried culinary herbs for the presence of S. chartarum chemotype S, to assess the potential risk of a contamination of foods with macrocyclic trichothecenes. In total, 50 Stachybotrys isolates from different types of culinary herbs ( n  = 100) such as marjoram ( Origanum majorana Linné (L.)), oregano ( Origanum vulgare L.), thyme ( Thymus vulgaris L.), and savory ( Satureja hortensis L.) were examined by MTT-cell culture test (effect-based bioassay), ELISA, and by liquid chromatography tandem mass spectrometry (LC-MS/MS). Selected toxic and non-toxic isolates ( n  = 15) were genetically characterized by PCR and sequencing. Five isolates (10 %) were highly toxic in the MTT-cell culture test, and the production of macrocyclic trichothecenes was proven by ELISA and LC-MS/MS. These five isolates were genetically confirmed as S. chartarum chemotype S. To the best of our knowledge, this is the first report about a contamination of dried culinary herbs with toxigenic S. chartarum .