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Drug-resistant microorganisms ('superbugs') present a serious challenge to the success of antimicrobial treatments. Subsequently, there is a crucial need for novel bio-control agents. Many antimicrobial peptides (AMPs) show a broad-spectrum activity against bacteria, fungi or viruses and are strong candidates to complement or substitute current antimicrobial agents. Some AMPs are also effective against protozoa or cancer cells. The tryptophan (Trp)-rich peptides (TRPs) are a subset of AMPs that display potent antimicrobial activity, credited to the unique biochemical properties of tryptophan that allow it to insert into biological membranes. Further, many Trp-rich AMPs cross bacterial membranes without compromising their integrity and act intracellularly, suggesting interactions with nucleic acids and enzymes. In this work, we overview some archetypal TRPs derived from natural sources, i.e., indolicidin, tritrpticin and lactoferricin, summarising their biochemical properties, structures, antimicrobial activities, mechanistic studies and potential applications. [ABSTRACT FROM AUTHOR]

A MALDI-TOF MS 1 1 Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry. -based imipenem hydrolysis assay was modified by adding ZnSO 4 . This improved detection of metallo-β-lactamase producing strains without compromising detection of other carbapenemase types. Using 129 genetically characterized Gram-negative bacilli, the sensitivity and specificity were 98.5% (95% confidence interval [CI]: 91.9–99.7%) and 100% (95% CI: 94.3–100%), respectively. [ABSTRACT FROM AUTHOR]

The puroindoline genes are causatively associated with wheat grain hardness, a commercially significant property. The proteins puroindoline (PIN) A and B are both required in their wild-type (WT) to impart soft grain texture, and absence of/mutations in either/both PIN(s) results in hard wheat. However, there is no biochemical clarity yet that explains this interdependence. This work critically analyses the roles of the tryptophan-rich domain (TRD), the little-known hydrophobic domain (HD), and certain other residues, in the physical associations of PINs. Site-directed mutagenesis-PCR was used to delete the TRD or HD and introduce an Arg39Gly substitution in PINA. The PINB-D1c mutant (Leu60Pro) was also investigated. The yeast two-hybrid system was used to assess the protein-protein interactions (PPI) of proteins. The TRD deletion or Arg39Gly substitution in PINA did not adversely affect its PPI, while deletion of HD resulted in a significant reduction. No effect on PPI was observed for Leu60Pro PINB. The results of this expression system strongly suggest that the HD is essential (but not sufficient) in higher-order associations of PINs. We propose a two-event model that explains the co-operative action of the PINs and why mutations outside the TRD may alter grain texture. [ABSTRACT FROM AUTHOR]

Objectives: Heparan sulphate mimetics, particularly heparin (Hep), have previously been shown to considerably inhibit infection of enterovirus 71 (EV71) in Vero cells. Therefore, in this study, a genome-wide DNA microarray was performed to gain insight into the mechanism(s) of action of Hep against infection of a human neural cell line, SK-N-SH, with a clinical strain of EV71. Methods: This study focused on a selection of EV71-induced genes whose expression profiling was exclusively affected by the antiviral activity of Hep. The selection procedure was performed through a statistical multi-level comparison with the following controls: negative control cells, compound control (cells treated with Hep only), virus control (cells treated with virus only) and treatment control (EV71-infected cells treated with Hep). Results: Overall, of more than 30,000 genes studied, 14 well-known annotated genes were selected that may be targets for the antiviral activity of Hep against EV71 infection in neural cells. For most of these genes, Hep appeared to modulate the impact of EV71 infection on the expression pattern of the genes. Conclusions: The findings of this research may provide initial assistance in new directions for studies to design molecular drug targets against EV71 infection. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Highlights: [•] Overlapping and long distance PCR were used to obtain cDNA of the full-length EV 71 genome. [•] EV 71 cDNA clones obtained with the long distance PCR were infectious in cell culture. [•] In vitro RNAs with the poly(A) tail of 18 or 30 adenines showed similar infectivity. [•] Extra bases downstream of the poly(A) tail did not reduce the infectivity of the in vitro RNA transcripts. [Copyright &y& Elsevier]

The emergence of drug resistant variants of the influenza virus has led to a need to identify novel and effective antiviral agents. As an alternative to synthetic drugs, the consolidation of empirical knowledge with ethnopharmacological evidence of medicinal plants offers a novel platform for the development of antiviral drugs. The aim of this study was to identify plant extracts with proven activity against the influenza virus. Extracts of fifty medicinal plants, originating from the tropical rainforests of Borneo used as herbal medicines by traditional healers to treat flu-like symptoms, were tested against the H1N1 and H3N1 subtypes of the virus. In the initial phase, in vitro micro-inhibition assays along with cytotoxicity screening were performed on MDCK cells. Most plant extracts were found to be minimally cytotoxic, indicating that the compounds linked to an ethnomedical framework were relatively innocuous, and eleven crude extracts exhibited viral inhibition against both the strains. All extracts inhibited the enzymatic activity of viral neuraminidase and four extracts were also shown to act through the hemagglutination inhibition (HI) pathway. Moreover, the samples that acted through both HI and neuraminidase inhibition (NI) evidenced more than 90% reduction in virus adsorption and penetration, thereby indicating potent action in the early stages of viral replication. Concurrent studies involving Receptor Destroying Enzyme treatments of HI extracts indicated the presence of sialic acid-like component(s) that could be responsible for hemagglutination inhibition. The manifestation of both modes of viral inhibition in a single extract suggests that there may be a synergistic effect implicating more than one active component. Overall, our results provide substantive support for the use of Borneo traditional plants as promising sources of novel anti-influenza drug candidates. Furthermore, the pathways involving inhibition of hemagglutination could be a solution to the global occurrence of viral strains resistant to neuraminidase drugs. [ABSTRACT FROM AUTHOR]

The puroindoline proteins (PINA and PINB) of wheat display lipid-binding properties which affect the grain texture, a critical parameter for wheat quality. Interestingly, the same proteins also display antibacterial and antifungal properties, attributed mainly to their Tryptophan-rich domain (TRD). Synthetic peptides based on this domain also display selectivity towards bacterial and fungal cells and do not cause haemolysis of mammalian cells. However, the mechanisms of these activities are unclear, thus limiting our understanding of the in vivo roles of PINs and development of novel applications. This study investigated the mechanisms of antimicrobial activities of synthetic peptides based on the TRD of the PINA and PINB proteins. Calcein dye leakage tests and transmission electron microscopy showed that the peptides PuroA, Pina-M and Pina-W→F selectively permeabilised the large unilamellar vesicles (LUVs) made with negatively charged phospholipids mimicking bacterial membranes, but were ineffective against LUVs made with zwitterionic phospholipids mimicking eukaryotic membranes. Propidium iodide fluorescence tests of yeast (Saccharomyces cerevisiae) cells showed the peptides were able to cause loss of membrane integrity, PuroA and Pina-M being more efficient. Scanning electron micrographs of PINA-based peptide treated yeast cells showed the formation of pits or pores in cell membranes and release of cellular contents. Gel retardation assays indicated the peptides were able to bind to DNA in vitro, and the induction of filamental growth of E. coli cells indicated in vivo inhibition of DNA synthesis. Together, the results strongly suggest that the PIN-based peptides exert their antimicrobial effects by pore formation in the cell membrane, likely by a carpet-like mechanism, followed by intracellular mechanisms of activity. [ABSTRACT FROM AUTHOR]

Peptides modelled on the tryptophan rich domain of puroindolines and the related grain softness protein-1 have a broad range of antibacterial and antifungal activities. With the aims of further investigating the activities of these antimicrobial peptides we studied their activity against wheat rust diseases and environmental stability. PINA-based peptides were found to have high pH and thermal stability in addition to being stable over long periods at room temperature. These properties could make them excellent candidates as preservatives in food. PuroA, Pina-R39G and PuroB peptides adversely affected the morphology of the stripe rust spores ( Puccinia striiformis f. sp. tritici), while PuroA and PuroB showed moderate inhibition of their germination. Additionally, GSP-5D reduced the germination of leaf rust spores ( P. triticina). PuroA and PuroB sprayed onto stripe rust infected plants effected a moderate reduction in the number of stripe rust uredinia on wheat seedlings, as did PuroB sprayed onto the seedlings and allowed to coat the leaves for 5 day prior to spore infection. The results suggest that the presence of the PIN-based peptides may lower frequency of initial infection foci. [ABSTRACT FROM AUTHOR]

Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Although there are more than 3000 dressing types in the wound management market, new developments in more efficient wound dressings will require innovative approaches such as embedding antibacterial additives into wound-dressing materials. The lack of novel antibacterial agents and the misuse of current antibiotics have caused an increase in antimicrobial resistance (AMR) which is estimated to cause 10 million deaths by 2050 worldwide. These ongoing challenges clearly indicate an urgent need for developing new antibacterial additives in wound dressings targeting microbial pathogens. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs. Some of the plant-based antibacterial additives, such as essential oils and plant extracts, have been previously used in wound dressings; however, there is another source of plant-derived antibacterial additives, i.e., those produced by symbiotic endophytic fungi, that show great potential in wound dressing applications. Endophytes represent a novel, natural, and sustainable source of bioactive compounds for therapeutic applications, including as efficient antibacterial additives for chronic wound dressings. This review examines and appraises recent developments in bioactive wound dressings that incorporate natural products as antibacterial agents as well as advances in endophyte research that show great potential in treating chronic wounds. [ABSTRACT FROM AUTHOR]

Abstract: The puroindoline genes Pina-D1 and Pinb-D1 located at the Ha locus on chromosome 5D of common wheat are considered the most important genetic determinants of grain hardness. The recent identification of Pinb-2 genes on group 7 chromosomes emphasises the need for detailed analysis of the genetics of this important trait. This study focussed on the analysis of Pinb-2 genes from accessions of hexaploid, tetraploid and diploid wheat, to address key questions related to their diversity and possible roles. Extensive DNA sequence heterogeneity was identified in the form of single nucleotide polymorphisms (SNPs), leading to seventeen reproducible haplotypes, of which thirteen are new. The results confirmed the known groups Pinb-2v1 to Pinb-2v5, identified a new group Pinb-2v6, and showed that the Pinb-2 genes comprised a small multigene family, at least in some genomes. The putative proteins exhibited changes at the important tryptophan-rich domain as well as basic and hydrophobic residues. A new Pina-D1 allele (at Ha locus) was also identified, designated Pina-D1t, with a premature stop codon at the TRD. Additionally, peptides designed on PINB-2 proteins displayed activity against bacteria and phytopathogenic fungi. The data strongly support the Pinb-2 genes being functionally relevant to roles including influencing grain texture. [Copyright &y& Elsevier]

A number of human activities result in environmental contamination with copper compounds that can cause severe detrimental effects on the ecosystem as well as human health. The physico-chemical methods of metal detection have limitations such as inability to distinguish between total versus bio-available metals and differences in metal uptake in different organisms. The heavy metal resistance-encoding genetic systems of certain bacteria provide critical tools for development of biosensors for these purposes. This study reports a copper biosensor utilizing the cop operon of the heavy metal resistant bacterial isolate, Achromobacter sp. AO22, isolated from a contaminated site in Australia. A section located between the divergently transcribed putative response regulator gene copR and multicopper oxidase gene copA that included a palindromic cop box was identified as a copper-responsive promoter using a lacZ reporter construct, pCOPRP, in E. coli. The expression was found to be enhanced by inclusion of copR. Another engineered strain, AO22(pCOPRP), showed stronger induction, and the lacZ expression in both backgrounds was enhanced significantly (250-400 fold) by copper but minimally by other metals. The construct in Achromobacter sp. AO22 thus has a high potential as biosensor for detecting copper bioavailability (hence potential toxicity) in a soil bacterial background, while the construct in E. coli is ideal for laboratory-based testing. [ABSTRACT FROM AUTHOR]

Abstract: The puroindoline (PIN) proteins in the wheat grain are considered the primary genetic basis of texture. Their lipid-binding nature that enables an effect on texture is also likely related to their antimicrobial properties. A number of mutations leading to hard texture are reported, but their collateral effects on any antimicrobial activities are unknown. To evaluate whether antimicrobial activity is conserved at the tryptophan rich domain (TRD) and affected by point mutations, we designed a series of peptides based on the TRD of proteins encoded by the alleles Pina-D1a, Pina-D1m, Pinb-D1a, Pinb-D1b, Pinb-D1l and Pinb-D1q, as well as by the grain softness protein-1, hordoindoline-a and hordoindoline-b genes. PuroA, Pina-M (Pro-35 to Ser), Hina and GSP-1 peptides displayed measurable antibacterial activity, Pina-M higher than PuroA. Replacement of Arg-39 with Gly decreased the activity considerably, and the five Trp residues in PuroA could not be substituted with Phe without major loss of activity. Except for Pinb-L (Lys-45 to Glu) and Hinb1a, all displayed antifungal activity and none displayed haemolytic activity. The work demonstrates a potential role for this protein family in pathogen protection, stresses the importance of Trp and basic residues, and suggests potential applications in food and health industries. [Copyright &y& Elsevier]

Oral diseases are major health problems with dental caries and periodontal diseases among the most important preventable global infectious diseases. Oral health influences the general quality of life and poor oral health is linked to chronic conditions and systemic diseases. The association between oral diseases and the oralmicrobiota is well established. Of themore than 750 species of bacteria that inhabit the oral cavity, a number are implicated in oral diseases. The development of dental caries involves acidogenic and aciduric Gram-positive bacteria (mutans streptococci, lactobacilli and actinomycetes). Periodontal diseases have been linked to anaerobic Gram-negative bacteria (Porphyromonas gingivalis, Actinobacillus, Prevotella and Fusobacterium). Given the incidence of oral disease, increased resistance by bacteria to antibiotics, adverse affects of some antibacterial agents currently used in dentistry and financial considerations in developing countries, there is a need for alternative prevention and treatment options that are safe, effective and economical. While several agents are commercially available, these chemicals can alter oral microbiota and have undesirable side-effects such as vomiting, diarrhea and tooth staining. Hence, the search for alternative products continues and natural phytochemicals isolated from plants used as traditional medicines are considered as good alternatives. In this review, plant extracts or phytochemicals that inhibit the growth of oral pathogens, reduce the development of biofilms and dental plaque, influence the adhesion of bacteria to surfaces and reduce the symptoms of oral diseases will be discussed further. Clinical studies that have investigated the safety and efficacy of such plant-derived medicines will also be described. [ABSTRACT FROM AUTHOR]

Many children with autism spectrum disorders (ASDs) suffer from gastrointestinal problems such as diarrhoea, constipation and abdominal pain. Such symptoms may be due to a disruption of the indigenous gut microbiota promoting the overgrowth of potentially pathogenic microorganisms. These observations have stimulated investigations into possible abnormalities of intestinal microbiota in autistic patients. The purpose of the present study was to determine if a relationship exists between ASD severity (mild - severe) and gastrointestinal (GI) microbial populations. The faecal microbiota of 22 male and 6 female participants with ASDs (aged 2-14 years) were analyzed by standard microbial culture methods and compared within-group (based on ASD severity) and with a standard laboratory reference range. Comparisons between children with mild ASD and those with moderate to severe ASD, as well as comparisons to a neurotypical control group previously reported, revealed that no significant differences appear to exist in the composition of the gut microbiota. Nevertheless, examination of each individual's gut microbial composition showed 10 cases of unusual findings which means 1 out of 3 cases have unusual microbiota. Our data do not support consistent GI microbial abnormalities in ASD children, but the findings do suggest that aberrations may be found in a minority of ASD children. Further studies are required to determine the possible association between the microbiota and gastrointestinal dysfunctions in a subset of children with both ASD and gastrointestinal problems. [ABSTRACT FROM PUBLISHER]

Abstract: This study describes the characterisation of G8 rotavirus strains isolated from humans with acute gastroenteritis. Six G8 strains were detected in Australia between 2002 and 2008. Four were G8P[14] strains, one was G8P[8]+[14] and one was G8 P non-typeable. By polyacrylamide gel electrophoresis and enzyme immunoassay analysis, four G8 strains with visible RNA exhibited a long electropherotype and five G8 strains displayed subgroup I specificity. Sequence analysis of the VP7 gene indicated that the G8 strains exhibited the highest nucleotide and amino acid identity with a G8P[11] bovine rotavirus strain detected in Japan. VP4 sequence data of one G8P[14] strain revealed that the closest identity was to another human-bovine-like strain detected in Australia, MG6, a G6P[14] strain. The identification of G8 strains causing disease further extends the number of G8P[14] strains detected in Australian children, and indicates that there is a rare but ongoing presence of uncommon human strains within the community in Australia. [Copyright &y& Elsevier]

Abstract: Objective: Compare evaporation techniques in the work-up procedure of saliva samples for cortisol analysis by a previously validated liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. Design and methods: Samples were evaporated using freeze drying, centrifugal concentration, and nitrogen flow and analyzed by LC–MS/MS. Results: Cortisol concentrations detected using each technique did not significantly differ. Factors other than the recovery of cortisol were evaluated. Conclusions: Evaporation using freeze drying/centrifugal concentration is an automated process, reducing overall processing time for analysis of numerous samples. [Copyright &y& Elsevier]

Abstract: Listeria monocytogenes is a foodborne pathogen responsible for the disease listeriosis. Ethanolic extracts from two native Australian traditional medicinal plants, Eremophila alternifolia and Eremophila duttonii, have been found to inhibit the growth of L. monocytogenes. These plants were investigated for their ability to control the growth of L. monocytogenes in full cream milk and skim milk and in diluted homogenates of salami, pâté and brie cheese. Time-kill experiments indicated that the extracts were able to inhibit the growth of L. monocytogenes in food at 4°C and 37°C. However, components in the food appeared to inhibit the anti-listerial activity of the extracts, necessitating higher concentrations to control microbial growth relative to those used in laboratory media. Preliminary investigations suggested that the active components responsible for the antimicrobial activity of each extract are most likely to be terpenes or sterols. Our study suggests that natural products derived from medicinal plants have the potential to be used as food preservatives. [Copyright &y& Elsevier]

Parasitic nematodes infect almost all forms of life. In the human context, parasites are one of the major causative factors for physical and intellectual growth retardation in the developing world. In the agricultural setting, parasites have a great economic impact through a reduction in livestock performance or control cost. The main method of controlling these devastating conditions is the use of anthelmintic drugs. Unfortunately, there are only a few anthelmintic drug classes available in the market and significant resistance has developed in most of the parasitic species of livestock. Therefore, development of new anthelmintics with different modes of action is critical for sustainable parasitic control in the future. The drug development pipeline is broadly limited to two types of molecules, namely synthetic compounds and natural plant products. Compared to synthetic compounds, natural products are highly diverse, and many have historically proven valuable in folk medicine to treat various gastrointestinal ailments. This review focus on the use of traditional knowledge-based plant extracts in the development of new therapeutic leads, the approaches used as screening techniques, and common bottlenecks and opportunities in plant-based anthelmintic drug discovery. [ABSTRACT FROM AUTHOR]

Treatment with 70% ethanol has been proposed as a safe and effective way to inactive bacteria for transport between laboratories prior to identification by MALDI-TOF MS. Ethanol alone does not inactivate spore-forming bacteria and additional chemical or physical treatment is necessary to guarantee inactivation of bacterial spores. [ABSTRACT FROM AUTHOR]

• Low-cost growth medium was used to cultivate Sporosarcina pasteurii prepared in deionized water and tap water. • Soil biocementation treatment was performed through surface percolation method. • Analytical-grade cementation reagents can be replaced with technical-grade cementation reagents. • Utilizing technical-grade reagents for sand biocementation resulted in 47 to 51-fold cost reduction. The use of microbially induced carbonate precipitation (MICP) to produce biocementitious material for soil stabilization has emerged in recent decades as a sustainable alternative approach to conventional methods. However, the use of standard analytical-grade reagents for various MICP studies makes this technology very expensive and unsuitable for field-scale consideration. In this present study, the feasibility of using commercially available and inexpensive technical-grade reagents for the cultivation of ureolytic bacteria and enhancement of soil stabilization was investigated. Low-cost growth media prepared in deionized water and tap water were used to cultivate Sporosarcina pasteurii as a replacement to standard laboratory-grade media. Biocement treatment was carried out on sand columns using different concentrations (0.25–1.0 M) of technical-grade and analytical-grade cementation solutions via surface percolation method. After 92 h of treatment, the columns were cured for 3 weeks at room temperature (26 ± 2 °C) before analysing their respective surface strengths, CaCO 3 content, pH of effluents and sand microscopic structures. The results indicated that the growth of bacteria in low-cost cultivation medium was similar to that observed in the standard cultivation medium. Surface strengths and CaCO 3 contents of the consolidated samples were in the ranges of 11448.00 ± 69.00–4826.00 ± 00 kPa and 5.56 ± 1.15–33.24 ± 0.59%, respectively. Overall, the obtained results of the current study encourage future MICP studies to utilize commercially available technical-grade reagents for economical MICP field-scale trials. [ABSTRACT FROM AUTHOR]

The microbiome of the human gut is a complex assemblage of microorganisms that are in a symbiotic relationship with one another and profoundly influence every aspect of human health. According to converging evidence, the human gut is a nodal point for the physiological performance matrixes of the vital organs on several axes (i.e. gut-brain, gut-lung, etc). As a result of COVID-19, the importance of gut-lung dysbiosis (balance or imbalance) has been realised. In view of this, it is of utmost importance to develop a comprehensive understanding of the microbiome, as well as its dysbiosis. In this review, we provide an overview of the gut-lung axial microbiome and its importance in maintaining optimal health. Human populations have successfully adapted to geophysical conditions through traditional dietary practices from around the world. In this context, a section has been devoted to the traditional Indian system of medicine and its theories and practices regarding the maintenance of optimally customized gut health. [ABSTRACT FROM AUTHOR]

The microwave-assisted production of solid lipid nanoparticles (SLNs) is a novel technique reported recently by our group. The small particle size, solid nature and use of physiologically well-tolerated lipid materials make SLNs an interesting and potentially efficacious drug carrier. The main purpose of this research work was to investigate the suitability of microwave-assisted microemulsion technique to encapsulate selected ionic drug substances such as miconazole nitrate and econazole nitrate. The microwave-produced SLNs had a small size (250–300 nm), low polydispersity (<0.20), high encapsulation efficiency (72–87%) and loading capacity (3.6–4.3%). Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies suggested reduced crystallinity of stearic acid in SLNs. The release studies demonstrated a slow, sustained but incomplete release of drugs (<60% after 24 h) from microwave-produced SLNs. Data fitting of drug release data revealed that the release of both drugs from microwave-produced SLNs was governed by non-Fickian diffusion indicating that drug release was both diffusion- and dissolution- controlled. Anti-fungal efficacy of drug-loaded SLNs was evaluated on C. albicans . The cell viability studies showed that cytotoxicity of SLNs was concentration-dependent. These encouraging results suggest that the microwave-assisted procedure is suitable for encapsulation of ionic drugs and that microwave-produced SLNs can act as potential carriers of antifungal drugs. [ABSTRACT FROM AUTHOR]

Stearic acid-based solid lipid nanoparticles (SLNs) were prepared using the microwave assisted one-pot microemulsions procedure pioneered by our group. In this study, non-steroidal anti-inflammatory drugs (NSAIDs) including indomethacin, ketoprofen and nimesulide were selected as ideal “test” drugs, based on their poor water solubility. The model drugs were incorporated within the SLNs by the microwave-assisted procedure at the time of SLN production. The microwave-produced drug-loaded SLNs were evaluated in terms of their physicochemical characteristics, drug release behavior and their uptake into against A549 cell line (human lung epithelial cells). The microwave-produced drug-loaded SLNs had a small particle size distribution, negative zeta potential and high encapsulation efficiency. The drug release studies were consistent with a core-shell structure of SLNs (probably a drug-loaded shell) which results in biphasic drug release from the SLNs. The drug release kinetics suggested a good fit of the release data to the Makoid-Banakar model and was governed by Fickian diffusion. The drug-loaded SLNs showed concentration-dependent cytotoxicity and reduced IL-6 and IL-8 secretion in lipopolysaccharide-induced cells. All of the above findings suggest that the microwave-produced SLNs could be promising drug carriers of NSAIDs and will further facilitate their development for topical, oral and/or nasal administration. [ABSTRACT FROM AUTHOR]

Apicomplexan infections, such as giardiasis and cryptosporidiosis, negatively impact a considerable proportion of human and commercial livestock populations. Despite this, the molecular mechanisms of disease, particularly the effect on the body beyond the gastrointestinal tract, are still poorly understood. To highlight host–parasite–microbiome biochemical interactions, we utilised integrated metabolomics-16S rRNA genomics and metabolomics–proteomics approaches in a C57BL/6J mouse model of giardiasis and compared these to Cryptosporidium and uropathogenic Escherichia coli (UPEC) infections. Comprehensive samples (faeces, blood, liver, and luminal contents from duodenum, jejunum, ileum, caecum and colon) were collected 10 days post infection and subjected to proteome and metabolome analysis by liquid and gas chromatography–mass spectrometry, respectively. Microbial populations in faeces and luminal washes were examined using 16S rRNA metagenomics. Proteome–metabolome analyses indicated that 12 and 16 key pathways were significantly altered in the gut and liver, respectively, during giardiasis with respect to other infections. Energy pathways including glycolysis and supporting pathways of glyoxylate and dicarboxylate metabolism, and the redox pathway of glutathione metabolism, were upregulated in small intestinal luminal contents and the liver during giardiasis. Metabolomics-16S rRNA genetics integration indicated that populations of three bacterial families—Autopobiaceae (Up), Desulfovibrionaceae (Up), and Akkermanasiaceae (Down)—were most significantly affected across the gut during giardiasis, causing upregulated glycolysis and short-chained fatty acid (SCFA) metabolism. In particular, the perturbed Akkermanasiaceae population seemed to cause oxidative stress responses along the gut–liver axis. Overall, the systems biology approach applied in this study highlighted that the effects of host–parasite–microbiome biochemical interactions extended beyond the gut ecosystem to the gut–liver axis. These findings form the first steps in a comprehensive comparison to ascertain the major molecular and biochemical contributors of host–parasite interactions and contribute towards the development of biomarker discovery and precision health solutions for apicomplexan infections. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is the cause of the COVID-19 pandemic which has claimed more than 6.5 million lives worldwide, devastating the economy and overwhelming healthcare systems globally. The development of new drug molecules and vaccines has played a critical role in managing the pandemic; however, new variants of concern still pose a significant threat as the current vaccines cannot prevent all infections. This situation calls for the collaboration of biomedical scientists and healthcare workers across the world. Repurposing approved drugs is an effective way of fast-tracking new treatments for recently emerged diseases. To this end, we have assembled and curated a database consisting of 7817 compounds from the Compounds Australia Open Drug collection. We developed a set of eight filters based on indicators of efficacy and safety that were applied sequentially to down-select drugs that showed promise for drug repurposing efforts against SARS-CoV-2. Considerable effort was made to evaluate approximately 14,000 assay data points for SARS-CoV-2 FDA/TGA-approved drugs and provide an average activity score for 3539 compounds. The filtering process identified 12 FDA-approved molecules with established safety profiles that have plausible mechanisms for treating COVID-19 disease. The methodology developed in our study provides a template for prioritising drug candidates that can be repurposed for the safe, efficacious, and cost-effective treatment of COVID-19, long COVID, or any other future disease. We present our database in an easy-to-use interactive interface (CoviRx that was also developed to enable the scientific community to access to the data of over 7000 potential drugs and to implement alternative prioritisation and down-selection strategies. [ABSTRACT FROM AUTHOR]

Tween® 20 stabilised stearic acid solid lipid nanoparticles (SLNs) were prepared using a one-pot microwave-assisted microemulsion technique. Two model water-insoluble drugs, the carboxylic acid-based indomethacin, and the imidazole-based miconazole nitrate, were then used to load the SLNs, and their subsequent physical properties (particle size and zeta potential) were measured and used to predict dispersion stability. Drug-free SLNs had a particle size of 239 nm and a zeta potential of − 29 mV. Indomethacin-loaded SLNs had a particle size of 266 nm and zeta potential of − 30 mV. Miconazole-loaded SLNs had a particle size of 266 nm and zeta potential of + 15 mV. These values were found to be relatively stable (under mildly acidic conditions) and recommend the suitability of the SLNs as a drug carrier. In all cases, the particle size and zeta potential were shown to be pH-dependent. For particle size, a minimum value was obtained at approximately pH 5, which corresponds to the pKa of the lipid used (stearic acid) indicating stearic acid adsorption onto the surface is likely to be at least partly responsible for dispersion stability. We conclude that dispersion stability arises from a combination of electrostatic stability (from adsorbed stearic acid) and limited steric stability from non-ionic (Tween® 20) surface-associated micelles. Dispersions were found to be unstable under alkaline conditions despite the increasingly negative zeta potential of all dispersions. This was observed as an increasingly larger particle size at pH > 7 combined with the observation that particle sizes at pH > 7 were also unstable and continued to increase with time. Visual observations showed dispersions physically broke within a few days at pH values > 7. The encapsulation efficiency (EE) and loading capacity (LC) of drug-loaded SLNs were shown to be close to their theoretical maximum (100%) at low pH, but decreased to < 20%, in the case of indomethacin-loaded SLNs, at a pH >> 7. Interestingly, the EE and LC of miconazole-loaded SLNs when first formed were relatively unaffected by pH. pH control, therefore, is very important to particle stability, and the pH should be kept neutral to mildly acidic. [Display omitted] [ABSTRACT FROM AUTHOR]

Treated recreational water facilities, including swimming pools and water play parks, have often been implicated in infectious disease outbreaks. Addressing this problem is complex due to the multiple and interrelated factors contributing to outbreaks in these settings. These factors may relate to inappropriate behaviours of users and operators, lack of and inconsistent regulation of these facilities, insufficient facility maintenance, and problems associated with the design of these facilities. Given the complexity of this issue, we argue that the Socio-Ecological Model (SEM) provides a useful framework to help identify the multi-level influences and factors that have implications for designing interventions to prevent this public health problem, whilst assisting in guiding future research in this area. We apply the SEM to the current literature to help identify the influences and factors contributing to infectious disease outbreaks in treated recreational water facilities to support this argument. We also identify several gaps in the existing research that would benefit from further examination to help prevent infectious disease outbreaks in treated recreational water facilities such as public swimming pools and water play parks. [ABSTRACT FROM AUTHOR]

Investigations into particle-mediated chlorination resistance were undertaken for three different bacteria (Escherichia coli ATCC 25922 and environmental isolates of Pseudomonas fluorescens and Serratia marcescens) and three different surfaces (goethite, environmental particles and surface-modified environmental particles). P. fluorescens demonstrated greater hydrophobicity than both other strains and proved the most adherent bacterium over all substrata investigated. Particle-mediated resistance to chlorination was investigated using short bacteria-particle association times and activity assays that employed sensitive epifluorescent detection. Consistent with adhesive behaviours, the bacterial strain that demonstrated the greatest particle-mediated chlorination resistance was the environmental strain of P. fluorescens. Resistance was observed to vary with both bacteria and particle type, and demonstrated a moderate correlation with adhesion (r² ≥ 0.65). The short-term approach employed in our study demonstrates particle-mediated protection without the commonly assumed requirements of extracellular polymeric substances (EPS) or a large particle-based chlorine demand. Consequently, we have linked resistance with adhesion capacities and demonstrated a limit to resistance in the presence of additional particle protective sites (through increased turbidity) which appears to be driven by intra-population variance in bacterial surface characteristics. Finally, we observed important differences between behaviours of environmental versus laboratory-derived bacterial strains and particles, which highlight the importance of employing both approaches in characterising "real world" systems. [ABSTRACT FROM AUTHOR]

Abstract: Listeria is represented by ten known species, comprising pathogenic and non-pathogenic variants. Listeria monocytogenes is the type species and is primarily pathogenic to humans and causes serious illness. As a result, most countries have a zero tolerance towards the presence of Listeria in foods. Therefore, in order to ensure food safety, robust techniques for detection are required. This paper describes a proof-of-concept application of a metabolomic technique for the rapid detection of Listeria, applied to nutrient media and a complex food sample (milk) inoculated with a pathogenic Listeria strain (L. monocytogenes). It was found that a profile of intracellular and extracellular metabolites associated with L. monocytogenes could be obtained using gas chromatography coupled to orthogonal acceleration time-of-flight mass spectrometry (GC-oaToFMS). Chemometric analysis showed that it is possible to differentiate between the uninoculated samples and samples inoculated with Listeria based on L. monocytogenes metabolic activity. This research demonstrates that metabolomics has the potential for rapidly identifying food contaminated with Listeria and could provide a means for enhancing monitoring programmes and ensuring food safety. [Copyright &y& Elsevier]

Hydrothermal-treated (autoclaved) winery waste was degraded by Trichoderma harzianum, Aspergillus niger, Penicillium chrysogenum and Penicillium citrinum. Quantification of lignins, reducing sugars, pentoses and enzyme assays for cellulase, β-glucosidase and xylanase were performed. Lignin content increased from 36% in untreated waste to 63% in autoclaved substrate. Lignin degradation of 9% and 4.2% was achieved by P. chrysogenum and A. niger, respectively. Reducing sugars decreased by 1.2 and 0.7kg/m³3 in T. harzianum and P. citrinum cultures, respectively. Pentose utilization was also considerable across all cultures. Cellulase and xylanase activities were higher in A. niger cultures at 45U and 335U, respectively. It also showed high β-glucosidase activity of 155U, marginally less than P. citrinum (180U). Autoclaving hydrolyzed hemicelluloses and crystalline cellulose, converting the latter to a more degradable amorphous form. The results suggest that successive hydrothermal and fungal treatments produce greater lignocellulose degradation than regular fermentation. [ABSTRACT FROM AUTHOR]

Solid lipid nanoparticles (SLNs) are a well-tolerated lipid carrier system due to the employment of a physiological and/or biodegradable lipid matrix. Physicochemical properties such as particle size, polydispersity index (PI) and zeta potential are SLN quality response parameters. Increased particle size is a good indicator of in-vitro instability. This work focuses on the importance of selecting the lipid matrices and excipients that can achieve the particle size and stability required if such formulations are to be utilised in the pharmaceutical market. With the aim of understanding the influence of variation in SLN composition (lipid and emulsifier concentration), a Taguchi model of experimental design was applied. Tested factors included the concentration of lipid (stearic acid) and the concentration of Tween®20. SLNs were successfully prepared by a microemulsion-based technique. Based on the hydrophilic lipophilic balance (HLB), different combinations of emulsifiers/co-emulsifiers (Tween®20/Span®20, Tween®20/Span®80, Tween®20/n-butanol, and Tween®20/iso-propanol) were also used to control the physicochemical properties of SLNs. The influence of pH (addition of HCl or NaOH) and electrolyte (addition of NaCl), both during and after the preparation, were also investigated on selected SLN formulations. Slightly polydispersed (PI < 0.3) nanoparticles with a particle size < 450 nm and zeta potential range of +5 to -50 mV were developed. Physical stability of optimised stearic-acid based SLNs over 2 months were assessed by particle size measurement. SLNs were stable when refrigerated. These results suggest that thoughtful selection of lipid and lipid excipients is essential for successful preparation and physical stability of SLNs. This study facilitates the preliminary physicochemical characterisation for favourable encapsulation of lipophilic and hydrophilic drugs. [ABSTRACT FROM AUTHOR]

• Bacteriophages as the new alternatives to existing antimicrobial agents. • High dependency on antibiotics in the food production sector. • Phages are promising biocontrol agents for organic farming. Bacteriophages (phages) are the natural predators of bacteria. They have been widely studied in recent decades in the hope of finding new alternatives to combat bacterial infections and to solve healthcare issues arising from antibiotic-resistant bacteria. High dependency on antibiotics in food production has led to widespread resistance in bacteria across the human food chain while at the same time reducing the effectiveness of existing antibacterial agents. The application of phages as biocontrol agents in the food production sector is one of the fastest-growing fields of research, with promising results indicating the suitability of phage biocontrol. In this review, the application of phages against various foodborne pathogens of concern to the food industry, from production to consumption ('farm-to-fork'), will be described. Furthermore, with the increase in certified organic agricultural land and the rising consumer demand for organic foods, phage biocontrol could be a new approach to manage bacterial diseases that occur under organic agricultural settings where the use of chemical pesticides and antibiotics is prohibited. Thus, this review also assesses where phage biocontrol can be applied as an adjunct to current disease control methods used in organic farming practices. [ABSTRACT FROM AUTHOR]

Abstract: Listeria monocytogenes is an important foodborne pathogen responsible for non-invasive and invasive diseases in the elderly, pregnant women, neonates and immunocompromised populations. This bacterium has many similarities with other non-pathogenic Listeria species which makes its detection from food and environmental samples challenging. Subtyping of L. monocytogenes strains can prove to be crucial in epidemiological investigations, source tracking contamination from food processing plants and determining evolutionary relationships between different strains. In recent years there has been a shift towards the use of molecular subtyping. This has led to the development of new subtyping techniques such as multi-locus variable number tandem repeat analysis (MLVA) and multi-locus sequence based typing (MLST). This review focuses on the available methods for Listeria detection including immuno-based techniques and the more recently developed molecular methods and analytical techniques such as matrix-assisted laser desorption/ionisation time-of-flight based mass spectrometry (MALDI-TOF MS). It also includes a comparison and critical analysis of the available phenotypic and genotypic subtyping techniques that have been investigated for L. monocytogenes. [Copyright &y& Elsevier]

Enterococci, particularly vancomycin resistant enterococci (VRE), are a cause of continuing concern in hospitals due to their intrinsic resistance to many antibiotics and the increasing prevalence of acquired resistance to vancomycin. Furthermore, enterococci are able to survive for prolonged periods on surfaces making disinfection more difficult. This study investigated bacteriophage biocontrol as a novel means of disinfecting hard and porous surfaces contaminated with enterococci. Four enterococcal bacteriophages, designated ΦSUT1, ΦSUT2, ΦSUT3 and ΦSUT4, were isolated from sewage and landfill leachate, characterised and used as biocontrol agents in studies investigating the efficacy of phage in the disinfection of vancomycin susceptible enterococci (VSE) and VRE on glass and fabrics commonly found in hospitals. Sterile glass slides and swatches of fabrics were inoculated with 10 cfu enterococci and 10 pfu/ml phage. Inoculated surfaces were incubated at ambient temperature for 2 h and bacterial populations were recovered by plating onto KF streptococcus agar. ΦSUT1 produced significant reductions in growth of Enterococcus faecalis on all surfaces tested, while ΦSUT4 produced significant reductions in growth of VRE (M168600) on all surfaces except for polyester. Phage cocktails containing ΦSUT1 and ΦSUT6 produced greater reductions in growth of VRE (M252807) on all surfaces compared to treatments using either phage alone. Although the results from this study varied considerably, the promising findings from ΦSUT1 studies indicated that phage biocontrol of enterococci should be further explored using broader host range phages. [ABSTRACT FROM AUTHOR]

Despite the removal of the mercury (Hg)-based preservative thimerosal from vaccines listed on the Australian Immunization Program Schedule for children, concerns remain among some researchers and parents for the safety of the present schedule, in part due to a fear of residual trace levels of Hg. The purpose of this study was to independently assess childhood vaccines for the presence of Hg. Eight vaccines administered to children under the age of 5 yr were assessed for Hg content via a DMA-80 direct mercury analyzer. Seven of the 8 vaccines contained no detectable levels of Hg (less than 1 ppb); however, 1 vaccine (Infanrix hexa) tested positive for Hg at 10 ppb. The result was confirmed and validated by retesting the original sample. Follow-up testing was conducted on three additional samples of Infanrix hexa (one from the same production lot and two from a different lot). All three tested positive for Hg (average of 9.7 ppb). Although the levels of Hg detected are substantially lower than any established exposure safety limits, the results of this study reveal that inaccuracies exist in public health messages, professional communications, and official documentation regarding Hg content in at least one childhood vaccine. In the interests of public health, it is incumbent on vaccine manufacturers and responsible agencies such as the Therapeutic Goods Administration and the Federal Department of Health and Ageing to address this issue as a matter of urgency. [ABSTRACT FROM AUTHOR]

Background: Achromobacter sp. AO22 (formerly Alcaligenes sp. AO22), a bacterial strain isolated from a lead-contaminated industrial site in Australia, was previously found to be resistant to moderate to high levels of mercury, copper and other heavy metals. However, the nature and location of the genetic basis for mercuric ion resistance in this strain, had not been previously identified. Findings: Achromobacter sp. AO22 contains a functional mer operon with all four essential genes (merRTPA) and shows >99% DNA sequence identity to that of Tn501. The mer operon was present on a transposon, designated TnAO22, captured by introducing a broad-host-range IncP plasmid into Achromobacter sp. AO22 and subsequently transferring it to E. coli recipients. The transposition frequency of TnAO22 was 10-2 to 10-3 per target plasmid transferred. Analysis of TnAO22 sequence revealed it belonged to the Tn21 subgroup of the Tn3 superfamily of transposons, with the transposition module having >99% identity with Tn5051 of a Pseudomonas putida strain isolated from a water sample in New York. Conclusion: TnAO22 is thus a new variant of Tn5051 of the Tn3 superfamily and the transposon and its associated mercury resistance system are among the few such systems reported in a soil bacterium. Achromobacter sp. AO22 can thus be exploited for applications such as in situ mercury bioremediation of contaminated sites, or the mobile unit and mer operon could be mobilized to other bacteria for similar purposes. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the impact of academic stress on salivary cortisol concentrations and lactic acid bacteria activity. Whole, unstimulated saliva samples and faecal samples were collected from 23 healthy undergraduate students (23.0±6.8 years; range 18–44) over two 1-week periods: during the beginning of semester (low-stress baseline condition) and during the first week of exams (high-stress condition). Students also completed a series of questionnaires measuring perceived levels of stress, gastrointestinal symptoms, and nutritional intake. Significant findings indicated that faecal lactic acid bacterial levels were lower during the high-stress condition. Paralleling this, students rated perceived levels of stress as being greater during the exam period compared to the baseline condition. The findings from this study have provided further insight into the link between stress and gastrointestinal flora activity in humans. [Copyright &y& Elsevier]

The primary flavonoid, pinocembrin, is thought to have a variety of medical uses which relate to its reported anti-oxidant, anti-inflammatory, anti-microbial and anti-cancer properties. Some studies have reported that this flavonoid has anti-fibrotic activities. In this study, we investigated whether pinocembrin would impede fibrosis, dampen inflammation and improve lung function in a large animal model of pulmonary fibrosis. Fibrosis was induced in two localized lung segments in each of the 10 sheep participating in the study. This was achieved via two infusions of bleomycin delivered bronchoscopically at a two-week interval. Another lung segment in the same sheep was left untreated, and was used as a healthy control. The animals were kept for a little over 5 weeks after the final infusion of bleomycin. Pinocembrin, isolated from Eucalyptus leaves, was administered to one of the two bleomycin damaged lung segments at a dose of 7 mg. This dose was given once-weekly over 4-weeks, starting one week after the final bleomycin infusion. Lung compliance (as a measure of stiffness) was significantly improved after four weekly administrations of pinocembrin to bleomycin-damaged lung segments. There were significantly lower numbers of neutrophils and inflammatory cells in the bronchoalveolar lavage of bleomycin-infused lung segments that were treated with pinocembrin. Compared to bleomycin damaged lung segments without drug treatment, pinocembrin administration was associated with significantly lower numbers of immuno-positive CD8+ and CD4+ T cells in the lung parenchyma. Histopathology scoring data showed that pinocembrin treatment was associated with significant improvement in inflammation and overall pathology scores. Hydroxy proline analysis showed that the administration of pinocembrin did not reduce the increased collagen content that was induced by bleomycin in this model. Analyses of Masson's Trichrome stained sections showed that pinocembrin treatment significantly reduced the connective tissue content in lung segments exposed to bleomycin when compared to bleomycin-infused lungs that did not receive pinocembrin. The striking anti-inflammatory and modest anti-fibrotic remodelling effects of pinocembrin administration were likely linked to the compound's ability to improve lung pathology and functional compliance in this animal model of pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Detection of gastrointestinal nematodes (GIN) as both a qualitative and quantitative test is highly desirable. Methods such as multiplex and qPCR are capable of providing such results, but can be laborious and expensive. This paper presents a rapid, low-cost method of preparing GIN egg from faecal samples that produces DNA suitable for PCR analysis. We also describe a set of primers that are suitable for single-tube multiplex PCR. • Designed primers for simultaneous PCR of three gastrointestinal nematode (GIN) species in a single test tube. • Novel preparation method using milk cream separator for purifying GIN eggs from faecal debris. • Assessed different methods for extracting DNA from GIN eggs suitable for PCR. [ABSTRACT FROM AUTHOR]

• Manual labour was the most frequently reported main contributor to FEC testing cost. • Sample analysis was the most frequently reported main time contributor to testing. • Opinions between FEC test performers are diverse and lack commonality. Gastrointestinal nematode (GIN) infections cause millions of dollars of economic loss annually. Increasing cases of anthelmintic resistance have resulted in calls for restricted drug use and implementation of sustainable management practices to slow the rate of resistance. The limited uptake of available management systems and advice has sparked multiple surveys into the psychology and behaviours preventing uptake. These surveys have looked mainly at the farmers, the majority of whom have reported they rely on the advice of their local veterinarian or suppliers for treatment and management. However, there is little research into the psychology of veterinarians and people performing animal health testing on this topic. In the current study, a short survey of people performing faecal egg counts on animals was conducted. The survey focused on identifying areas for improving diagnosis to encourage uptake, and found other areas of interest worth further investigation. Respondents most frequently named manual labour as the main contributor to the cost of testing (65% of respondents) with analysis (42%) and sample preparation (32%) being the main contributors to time. In the survey comments, there was little consistency or commonality in the issues raised. The disparity between onsite and laboratory testers is an area worth investigation, particularly into how to co-ordinate behaviour and advice between proactive farmers and parasitology/veterinary services. Further investigation could provide better insight into how to encourage and maintain sustainable practices on farms. [ABSTRACT FROM AUTHOR]

The elimination of spore-forming bacteria is not guaranteed by current pasteurisation processes and is a challenging problem for the dairy industry. Given that Bacillus cereus sensu lato (B. cereus group) is an important foodborne pathogen and spoiler in the dairy industry, this study aimed at evaluating the prevalence and characteristics of B. cereus group in raw and pasteurised milk samples collected in Victoria, Australia. Isolated B. cereus group were tested for antimicrobial susceptibility, biofilm formation and virulence properties. Genetic diversity was assessed using ERIC-PCR. Proteomic profiling using MALDI-TOF MS and chemical profiling using Fourier-transform infrared (FTIR) spectroscopy were also applied for clustering of the isolates. Results showed 42.3% of milk samples contained B. cereus group, with a higher contamination level for pasteurised milk. Virulence studies identified genes nheA, nheB, hblA and nheC in most isolates and cyk gene in 46% of all isolates. Antimicrobial susceptibility testing showed a high prevalence of resistance towards ampicillin, ceftriaxone and penicillin. The biofilm-forming capacity of our isolates showed that most (53.7%) had the ability to form a biofilm. Genetic profiling using ERIC-PCR placed most B. cereus group isolates from pasteurised milk in the same cluster, indicating that they probably originated from a similar source. Raw milk isolates showed greater diversity indicating various sources. FTIR spectroscopy showed high agreement with genetic profiling. In contrast, low agreement between proteomic (MALDI-TOF MS) and genetic typing was observed. The present study showed that the FTIR spectroscopy could be adopted as a rapid tool for the typing of B. cereus group. Overall, the virulence and antimicrobial resistance characteristics, together with the ability of isolates to produce biofilm, indicate the importance of B. cereus group in the Australian dairy industry. [ABSTRACT FROM AUTHOR]

Oxaliplatin is a platinum-based chemotherapeutic used for cancer treatment. Its use associates with peripheral neuropathies and chronic gastrointestinal side-effects. Oxaliplatin induces immunogenic cell death by provoking the presentation of damage associated molecular patterns. The damage associated molecular patterns high-mobility group box 1 (HMGB1) protein exerts pro-inflammatory cytokine-like activity and binds to toll-like receptors (namely TLR4). Gastrointestinal microbiota may influence chemotherapeutic efficacy and contribute to local and systemic inflammation. We studied effects of oxaliplatin treatment on 1) TLR4 and high-mobility group box 1 expression within the colon; 2) gastrointestinal microbiota composition; 3) inflammation within the colon; 4) changes in Peyer’s patches and mesenteric lymph nodes immune populations in mice. TLR4+ cells displayed pseudopodia-like extensions characteristic of antigen sampling co-localised with high-mobility group box 1 -overexpressing cells in the colonic lamina propria from oxaliplatin-treated animals. Oxaliplatin treatment caused significant reduction in Parabacteroides and Prevotella1, but increase in Prevotella2 and Odoribacter bacteria at the genus level. Downregulation of pro-inflammatory cytokines and chemokines in colon samples, a reduction in macrophages and dendritic cells in mesenteric lymph nodes were found after oxaliplatin treatment. In conclusion, oxaliplatin treatment caused morphological changes in TLR4+ cells, increase in gram-negative microbiota and enhanced HMGB1 expression associated with immunosuppression in the colon. [ABSTRACT FROM AUTHOR]

Interest in endophytes as natural sources for new medicines was inspired by the discovery of paclitaxel-producing endophytic fungi. This study investigated the anti-cancer activity of extracts of endophytes isolated from two Australian plants, Eremophila longifolia (EL) and Eremophila maculata (EM). Endophytes were isolated from surface-sterilised leaf tissue, grown as pure cultures and identified by sequencing of Internal Transcribed Spacer (ITS) regions of the ribosomal DNA. To determine cytotoxicity, two leukaemic (MOLT-4, T-cell leukaemia; PreB-697, Pre-B leukaemia), a lung cancer cell line (A549) and a normal human fibroblast cell line were treated with endophyte extracts to assess cytotoxicity in relation to alternariol monomethyl ether (AME) and alternariol (AOH). Endophyte extracts that showed cell cytotoxicity were analysed by UV-HPLC to determine the metabolites. Pure AME and AOH, three extracts form Alternaria sp. (EM-6, EM-7 and EM-9) and one from Preussia minima (EL-14) were cytotoxic to the cancer cell lines. All cytotoxic endophytes contained AME and AOH, the most cytotoxic endophyte EM-6 also contained two unique peaks. These data indicate that these four endophyte extracts may have anti-cancer properties due to the presence of AME and AOH; however, the unique compounds found in the EM-6 extract may be exclusively cytotoxic and warrant further investigation. [ABSTRACT FROM AUTHOR]

To determine the mechanism(s) of action of antimicrobial peptides (AMPs) it is desirable to provide details of their interaction kinetics with cellular, sub-cellular and molecular targets. The synthetic peptide, PuroA, displays potent antimicrobial activities which have been attributed to peptide-induced membrane destabilization, or intracellular mechanisms of action (DNA-binding) or both. We used time-lapse fluorescence microscopy and fluorescence lifetime imaging microscopy (FLIM) to directly monitor the localization and interaction kinetics of a FITC- PuroA peptide on single Candida albicans cells in real time. Our results reveal the sequence of events leading to cell death. Within 1 minute, FITC-PuroA was observed to interact with SYTO-labelled nucleic acids, resulting in a noticeable quenching in the fluorescence lifetime of the peptide label at the nucleus of yeast cells, and cell-cycle arrest. A propidium iodide (PI) influx assay confirmed that peptide translocation itself did not disrupt the cell membrane integrity; however, PI entry occurred 25-45 minutes later, which correlated with an increase in fractional fluorescence of pores and an overall loss of cell size. Our results clarify that membrane disruption appears to be the mechanism by which the C. albicans cells are killed and this occurs after FITC-PuroA translocation and binding to intracellular targets. [ABSTRACT FROM AUTHOR]

To increase the efficiency of winery-derived biomass biodegradation, grape pomace was ultrasonicated for 20 min in the presence of 0.25 M, 0.5 M and 1.0 M KOH and 1.0 M NaOH. This was followed by treatment with a 1:1 ( v/v ) mix of crude enzyme preparation derived from Phanerochaete chrysosporium and Trametes versicolor for 18 h and a further 18 h treatment with a 60:14:4:2 percent ratio combination of enzymes derived from Aspergillus niger: Penicillium chrysogenum: Trichoderma harzianum : P. citrinum , repsectively. Process efficiency was evaluated by its comparison to biological only mixed fungal degradation over 16 days. Ultrasonication treatment with 0.5 M KOH followed by mixed enzyme treatment yielded the highest lignin degradation of about 13%. Cellulase, β-glucosidase, xylanase, laccase and lignin peroxidase activities of 77.9, 476, 5,390.5, 66.7 and 29,230.7 U/mL, respectively, were observed during biomass degradation. Gas chromatography–mass spectrometry (GC–MS) analysis of the degraded material identified commercially important compounds such as gallic acid, lithocholic acid, glycolic acid and lactic acid which were generated in considerable quantities. Thus, the combination of sonication pre-treatment and enzymatic degradation has the potential to considerably improve the breakdown of agricultural biomass and produce commercially useful compounds in markedly less time (<40 h) with respect to biological only degradation (16 days). [ABSTRACT FROM AUTHOR]

The application of metabolomics to biological samples has been a key focus in systems biology research, which is aimed at the development of rapid diagnostic methods and the creation of personalized medicine. More recently, there has been a strong focus towards this approach applied to non-invasively acquired samples, such as saliva and exhaled breath. The analysis of these biological samples, in conjunction with other sample types and traditional diagnostic tests, has resulted in faster and more reliable characterization of a range of health disorders and diseases. As the sampling process involved in collecting exhaled breath and saliva is non-intrusive as well as comparatively low-cost and uses a series of widely accepted methods, it provides researchers with easy access to the metabolites secreted by the human body. Owing to its accuracy and rapid nature, metabolomic analysis of saliva and breath (known as salivaomics and breathomics, respectively) is a rapidly growing field and has shown potential to be effective in detecting and diagnosing the early stages of numerous diseases and infections in preclinical studies. This review discusses the various collection and analyses methods currently applied in two of the least used non-invasive sample types in metabolomics, specifically their application in salivaomics and breathomics research. Some of the salient research completed in this field to date is also assessed and discussed in order to provide a basis to advocate their use and possible future scientific directions. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides are promising therapeutic alternatives to counter growing antimicrobial resistance. Their precise mechanism of action remains elusive, however, particularly with respect to live bacterial cells. We investigated the interaction of a fluorescent melittin analogue with single giant unilamellar vesicles, giant multilamellar vesicles, and bilamellar Gram-negative Escherichia coli (E. coli) bacteria. Time-lapse fluorescence lifetime imaging microscopy was employed to determine the population distribution of the fluorescent melittin analogue between pore state and membrane surface state, and simultaneously measure the leakage of entrapped fluorescent species from the vesicle (or bacterium) interior. In giant unilamellar vesicles, leakage from vesicle interior was correlated with an increase in level of pore states, consistent with a stable pore formation mechanism. In giant multilamellar vesicles, vesicle leakage occurred more gradually and did not appear to correlate with increased pore states. Instead pore levels remained at a low steady-state level, which is more in line with coupled equilibria. Finally, in single bacterial cells, significant increases in pore levels were observed over time, which were correlated with only partial loss of cytosolic contents. These observations suggested that pore formation, as opposed to complete dissolution of membrane, was responsible for the leakage of contents in these systems, and that the bacterial membrane has an adaptive capacity that resists peptide attack. We interpret the three distinct pore dynamics regimes in the context of the increasing physical and biological complexity of the membranes. [ABSTRACT FROM AUTHOR]

Refrigerated storage of raw milk promotes the growth of psychrotrophic bacteria, some of which produce heat-stable exoenzymes causing dairy product spoilage. The effects of storage conditions and season on the biodiversity of psychrotrophs in raw milk were examined using matrix-assisted laser desorption time of flight mass spectrometry and 16S rRNA analysis. The ability of psychrotrophs to produce protease, lipase and phospholipase C was determined. The predominant genera found were Pseudomonas (19.9%), Bacillus (13.3%), Microbacterium (5.3%), Lactococcus (8.6%), Acinetobacter (4.9%) and Hafnia (2.8%); a considerable number of isolates were hitherto unknown species and genera. Diversity varied significantly ( P < 0.05), depending on the storage temperature, time, initial microbiota and season. The predominant isolates showed significantly higher heat-stable exoenzyme activities after heating at 142 °C for 4 s. Improving the quality of milk products may require differential processing of raw milk depending on the type of microbiota present, storage temperature and seasonality. [ABSTRACT FROM AUTHOR]

Background: Parasitic roundworms (nematodes) cause substantial morbidity and mortality in livestock animals globally, and considerable productivity losses to farmers. The control of these nematodes has relied largely on the use of a limited number of anthelmintics. However, resistance to many of these these anthelmintics is now widespread, and, therefore, there is a need to find new drugs to ensure sustained and effective treatment and control into the future. Methods: Recently, we developed a screening assay to test natural, plant extracts with known inhibitory effects against the free-living worm Caenorhabditis elegans. Using this assay, we assessed here the effects of the extracts on motility and development of parasitic larval stages of Haemonchus contortus, one of the most important nematodes of small ruminants worldwide. Results: The study showed that two of five extracts from Picria fel-terrae Lour. have a significant inhibitory effect (at concentrations of 3-5 mg/ml) on the motility and development of H. contortus larvae. Although the two extracts originated from the same plant, they displayed different levels of inhibition on motility and development, which might relate to the presence of various active constituents in these extracts, or the same constituents at different concentrations in distinct parts of the plant. Conclusions: These results suggest that extracts from P. fel-terrae Lour. have promising anthelmintic activity and that more broadly, plant extracts are a potential rich source of anthelmintics to combat helminthic diseases. [ABSTRACT FROM AUTHOR]