Liver click dECM hydrogels for engineering hepatic microenvironments.

Decellularized extracellular matrix (dECM) hydrogels provide tissue-specific microenvironments which accommodate physiological cellular phenotypes in 3D in vitro cell cultures. However, their formation hinges on collagen fibrillogenesis, a complex process which limits regulation of physicochemical properties. Hence, achieving reproducible results with dECM hydrogels poses as a challenge. Here, we demonstrate that thiolation of solubilized liver dECM enables rapid formation of covalently crosslinked hydrogels via Michael type addition, allowing for precise control over mechanical properties and superior organotypic biological activity. Investigation of various decellularization methodologies revealed that treatment of liver tissue with Triton X-100 and ammonium hydroxide resulted in near complete DNA removal with significant retention of the native liver proteome. Chemical functionalization of pepsin-solubilized liver dECMs via 1-ethyl-3(3-dimethylamino)propyl carbodiimide (EDC)/N-hydroxysuccinimide (NHS) coupling of L-Cysteine created thiolated liver dECM (dECM-SH), which rapidly reacted with 4-arm polyethylene glycol (PEG)-maleimide to form optically clear hydrogels under controlled conditions. Importantly, Young's moduli could be precisely tuned between 1 - 7 kPa by varying polymer concentrations, enabling close replication of healthy and fibrotic liver conditions in in vitro cell cultures. Click dECM-SH hydrogels were cytocompatible, supported growth of HepG2 and HepaRG liver cells, and promoted liver-specific functional phenotypes as evidenced by increased metabolic activity, as well CYP1A2 and CYP3A4 activity and excretory function when compared to monolayer culture and collagen-based hydrogels. Our findings demonstrate that click-functionalized dECM hydrogels offer a highly controlled, reproducible alternative to conventional tissue-derived hydrogels for in vitro cell culture applications. STATEMENT OF SIGNIFICANCE: Traditional dECM hydrogels face challenges in reproducibility and mechanical property control due to variable crosslinking processes. We introduce a click hydrogel based on porcine liver decellularized extracellular matrix (dECM) that circumnavigates these challenges. After optimizing liver decellularization for ECM retention, we integrated thiol-functionalized liver dECM with polyethylene-glycol derivatives through Michael-type addition click chemistry, enabling rapid, room-temperature gelation. This offers enhanced control over the hydrogel's mechanical and biochemical properties. The resultant click dECM hydrogels mimic the liver's natural ECM and exhibit greater mechanical tunability and handling ease, facilitating their application in high-throughput and industrial settings. Moreover, these hydrogels significantly improve the function of HepaRG-derived hepatocytes in 3D culture, presenting an advancement for liver tissue cell culture models for drug testing applications.

Bioassay-Guided Fractionation of Pittosporum angustifolium and Terminalia ferdinandiana with Liquid Chromatography Mass Spectroscopy and Gas Chromatography Mass Spectroscopy Exploratory Study.

Bioprospecting native Australian plants offers the potential discovery of latent and novel bioactive compounds. The promising cytotoxic and antibacterial activity of methanolic extracts of Pittosporum angustifolium and Terminalia ferdinandiana led to further fractionation and isolation using our laboratory's bioassay-guided fractionation protocol. Hence, the aim of this study was to further evaluate the bioactivity of the fractions and subfractions and characterize bioactive compounds using liquid chromatography mass spectroscopy (LC-MS/MS) and gas chromatography MS (GC-MS). Compounds tentatively identified in P. angustifolium Fraction 1 using LC-ESI-QTOF-MS/MS were chlorogenic acid and/or neochlorogenic acid, bergapten, berberine, 8'-epitanegool and rosmarinic acid. GC-MS analysis data showed the presence of around 100 compounds, mainly comprising carboxylic acids, sugars, sugar alcohols, amino acids and monoalkylglycerols. Furthermore, the fractions obtained from T. ferdinandiana flesh extracts showed no cytotoxicity, except against HT29 cell lines, and only Fraction 2 exhibited some antibacterial activity. The reduced bioactivity observed in the T. ferdinandiana fractions could be attributed to the potential loss of synergy as compounds become separated within the fractions. As a result, the further fractionation and separation of compounds in these samples was not pursued. However, additional dose-dependent studies are warranted to validate the bioactivity of T. ferdinandiana flesh fractions, particularly since this is an understudied species. Moreover, LC-MS/GC-MS studies confirm the presence of bioactive compounds in P. angustifolium Fraction 1/subfractions, which helps to explain the significant acute anticancer activity of this plant. The screening process designed in this study has the potential to pave the way for developing scientifically validated phytochemical/bioactivity information on ethnomedicinal plants, thereby facilitating further bioprospecting efforts and supporting the discovery of novel drugs in modern medicine.

A salivary biomarker panel to detect liver cirrhosis.

Limited access to diagnostic tests for liver fibrosis remains one of the main reasons for late diagnosis, especially in rural and remote communities. Saliva diagnostics is accessible with excellent patient compliance. The aim of this study was to develop a saliva-based diagnostic tool for liver fibrosis/cirrhosis. Salivary concentrations of hyaluronic acid (HA), tissue inhibitor of metalloproteinase-1 (TIMP-1), and α-2-macroglobulin (A2MG) were significantly increased (p < 0.05) in patients with liver fibrosis/cirrhosis. By combining these biomarkers, we developed the Saliva Liver Fibrosis (SALF) score, which identified patients with liver cirrhosis with an area under the receiver operating characteristic curve (AUROC) of 0.970 and 0.920 in a discovery and validation cohorts, respectively. The SALF score had a performance that was similar to that of the current Fibrosis-4 (AUROC:0.740) and Hepascore (AUROC:0.979). We demonstrated the clinical utility of saliva to diagnose liver fibrosis/cirrhosis with a potential to improve the screening for cirrhosis in asymptomatic populations.

Proteome profiling of salivary small extracellular vesicles in glioblastoma patients.

BACKGROUND: Extracellular vesicles (EVs) play a critical role in intercellular communication under physiological and pathological conditions, including cancer. EVs cargo reflects their cell of origin, suggesting their utility as biomarkers. EVs are detected in several biofluids, and their ability to cross the blood-brain barrier has highlighted their potential as prognostic and diagnostic biomarkers in gliomas, including glioblastoma (GBM). Studies have demonstrated the potential clinical utility of plasma-derived EVs in glioma. However, little is known about the clinical utility of saliva-derived EVs in GBM. METHODS: Small EVs were isolated from whole mouth saliva of GBM patients pre- and postoperatively. Isolation was performed using differential centrifugation and/or ultracentrifugation. EVs were characterized by concentration, size, morphology, and EVs cell-surface protein markers. Protein cargo in EVs was profiled using mass spectrometry. RESULTS: There were no statistically significant differences in size and concentration of EVs derived from pre- and post GBM patients' saliva samples. A higher number of proteins were detected in preoperative samples compared to postoperative samples. The authors found four highly abundant proteins (aldolase A, 14-3-3 protein ε, enoyl CoA hydratase 1, and transmembrane protease serine 11B) in preoperative saliva samples from GBM patients with poor outcomes. Functional enrichment analysis of pre- and postoperative saliva samples showed significant enrichment of several pathways, including those related to the immune system, cell cycle and programmed cell death. CONCLUSIONS: This study, for the first time, demonstrates the feasibility of isolating and characterizing small EVs from pre- and postoperative saliva samples from GBM patients. Preliminary findings encourage further large cohort validation studies on salivary small EVs to evaluate prognosis in GBM.

Acontia, a Specialised Defensive Structure, Has Low Venom Complexity in Calliactis polypus.

Phylum Cnidaria represents a unique group among venomous taxa, with its delivery system organised as individual organelles, known as nematocysts, heterogeneously distributed across morphological structures rather than packaged as a specialised organ. Acontia are packed with large nematocysts that are expelled from sea anemones during aggressive encounters with predatory species and are found in a limited number of species in the superfamily Metridioidea. Little is known about this specialised structure other than the commonly accepted hypothesis of its role in defence and a rudimentary understanding of its toxin content and activity. This study utilised previously published transcriptomic data and new proteomic analyses to expand this knowledge by identifying the venom profile of acontia in Calliactis polypus. Using mass spectrometry, we found limited toxin diversity in the proteome of acontia, with an abundance of a sodium channel toxin type I, and a novel toxin with two ShK-like domains. Additionally, genomic evidence suggests that the proposed novel toxin is ubiquitous across sea anemone lineages. Overall, the venom profile of acontia in Calliactis polypus and the novel toxin identified here provide the basis for future research to define the function of acontial toxins in sea anemones.

A cut above the rest: oxidative stress in chronic wounds and the potential role of polyphenols as therapeutics.

OBJECTIVES: The pathophysiology of chronic wounds typically involves redox imbalance and inflammation pathway dysregulation, often with concomitant microbial infection. Endogenous antioxidants such as glutathione and tocopherols are notably reduced or absent, indicative of significant oxidative imbalance. However, emerging evidence suggests that polyphenols could be effective agents for the amelioration of this condition. This review aims to summarise the current state of knowledge surrounding redox imbalance in the chronic wound environment and the potential use of polyphenols for the treatment of chronic wounds. KEY FINDINGS: Polyphenols provide a multi-faceted approach towards the treatment of chronic wounds. Firstly, their antioxidant activity allows direct neutralisation of harmful free radicals and reactive oxygen species, assisting in restoring redox balance. Upregulation of pro-healing and anti-inflammatory gene pathways and enzymes by specific polyphenols further acts to reduce redox imbalance and promote wound healing actions, such as proliferation, extracellular matrix deposition and tissue remodelling. Finally, many polyphenols possess antimicrobial activity, which can be beneficial for preventing or resolving infection of the wound site. SUMMARY: Exploration of this diverse group of natural compounds may yield effective and economical options for the prevention or treatment of chronic wounds.

Hitting the sweet spot: A systematic review of the bioactivity and health benefits of phenolic glycosides from medicinally used plants.

Phenolic acid and flavonoid glycosides form a varied class of naturally occurring compounds, characterised by high polarity-resulting from the glycone moiety-and the presence of multiple phenol functionalities, which often leads to strong antioxidant activity. Phenolic glycosides, and in particular flavonoid glycosides, may possess strong bioactive properties with broad spectrum activity. This systematic literature review provides a detailed overview of 28 studies examining the biological activity of phenolic and flavonoid glycosides from plant sources, highlighting the potential of these compounds as therapeutic agents. The activity of glycosides depends upon the biological activity type, identity of the aglycone and the identity and specific location of the glycone moiety. From studies reporting the activity of both glycosides and their respective aglycones, phenolic glycosides appear to generally be a storage/reserve pool of precursors of more bioactive compounds. The glycosylated compounds are likely to be more bioavailable compared to their aglycone forms, due to the presence of the sugar moieties. Hydrolysis of the glycoside in the in vivo environment would release the free aglycone, potentiating their biological activity. However, further high-quality studies are needed to firmly establish the clinical efficacy of glycosides from many of the plant species studied.

Antioxidative and therapeutic potential of selected Australian plants: A review.

ETHNOPHARMACOLOGICAL RELEVANCE: Numerous common pharmaceuticals, including anti-cancer, antiviral and antidiabetic drugs, are derived from traditional plant-derived medicines. With approximately 25,000 species of flora occurring in Australia that are adapted to the harsh environment, there is a plethora of novel compounds awaiting research in the context of their medicinal properties. Anecdotal accounts of plant-based medicines used by the Australian Aboriginal and Torres Strait Islander peoples clearly illustrates high therapeutic activity. AIM: This review aims to demonstrate the medicinal potentials of selected native Australian plants based on scientific data. Furthermore, it is anticipated that work presented here will contribute towards enhancing our knowledge of native plants from Australia, particularly in the prevention and potential treatment of disease types such as cancer, microbial and viral infections, and diabetes. This is not meant to be a comprehensive study, rather it is meant as an overview to stimulate future research in this field. METHODS: The EBSCOhost platform which included PubMed, SciFinder, Web of Knowledge, Scopus, and ScienceDirect databases were searched for papers using the keywords: medicinal plants, antioxidative, antimicrobial, antibacterial, anticancer, anti-tumor, antiviral or antidiabetic, as well as Australian, native, traditional and plants. The selection criteria for including studies were restricted to articles on plants used in traditional remedies which showed antioxidative potential and therapeutic properties such as anticancer, antimicrobial, antiviral and antidiabetic activity. RESULTS: Some plants identified in this review which showed high Total Phenolic Content (TPC) and antioxidative capacity, and hence prominent bioactivity, included Tasmannia lanceolata (Poir.) A.C. Sm., Terminalia ferdinandiana Exell, Eucalyptus species, Syzygium species, Backhousia citriodora F.Muell., Petalostigma species, Acacia species, Melaleuca alternifolia (Maiden & Betche) Cheel, Eremophila species, Prostanthera rotundifolia R.Br., Scaevola spinescens R. Br. and Pittosporum angustifolium Lodd. The majority of studies found polar compounds such as caffeic acid, coumaric acid, chlorogenic acid, quercetin, anthocyanins, hesperidin, kaempferol, catechin, ellagic acid and saponins to be the active components responsible for the therapeutic effects. Additionally, mid to non-polar volatile organic compounds such as meroterpenes (serrulatanes and nerol cinnamates), monoterpenes (1,8-cineole and myodesert-1-ene), sesquiterpenes, diterpenes and triterpenes, that are known only in Australian plants, have also shown therapeutic properties related to traditional medicine. CONCLUSION: Australian plants express a diverse range of previously undescribed metabolites that have not been given full in vitro assessment for human health potential. This review has included a limited number of plant species of ethnomedicinal significance; hundreds of plants remain in need of exploration and detailed study. Future more elaborate studies are therefore required to screen out and purify lead bioactive compounds against numerous other disease types. This will not only improve our knowledge on the phytochemistry of Australian native flora, but also provide a platform to understand their health-promoting and bioactive effects for pharmaceutical interventions, nutraceuticals, cosmetics, and as functional foods. Finally, plant-derived natural compounds (phytochemicals), as well as plant-based traditional remedies, are significant sources for latent and novel drugs against diseases. Extensive investigation of native medicinal plants may well hold the key to novel drug discoveries.

The use of minimally invasive biomarkers for the diagnosis and prognosis of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a common cause of cancer-related deaths worldwide. Despite advances in systemic therapies, patient survival remains low due to late diagnosis and frequent underlying liver diseases. HCC diagnosis generally relies on imaging and liver tissue biopsy. Liver biopsy presents limitations because it is invasive, potentially risky for patients and it frequently misrepresents tumour heterogeneity. Recently, liquid biopsy has emerged as a way to monitor cancer progression in a non-invasive manner. Tumours shed content into the bloodstream, such as circulating tumour cells (CTCs), circulating nucleic acids, extracellular vesicles and proteins, that can be isolated from biological fluids of patients with HCC. These biomarkers provide knowledge regarding the genetic landscape of tumours and might be used for diagnostic or prognostic purposes. In this review, we summarize recent literature on circulating biomarkers for HCC, namely CTCs, circulating tumour DNA (ctDNA), RNA, extracellular vesicles and proteins, and their clinical relevance in HCC.

Natural product-derived phytochemicals as potential agents against coronaviruses: A review.

Coronaviruses are responsible for a growing economic, social and mortality burden, as the causative agent of diseases such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), avian infectious bronchitis virus (IBV) and COVID-19. However, there is a lack of effective antiviral agents for many coronavirus strains. Naturally existing compounds provide a wealth of chemical diversity, including antiviral activity, and thus may have utility as therapeutic agents against coronaviral infections. The PubMed database was searched for papers including the keywords coronavirus, SARS or MERS, as well as traditional medicine, herbal, remedy or plants, with 55 primary research articles identified. The overwhelming majority of publications focussed on polar compounds. Compounds that show promise for the inhibition of coronavirus in humans include scutellarein, silvestrol, tryptanthrin, saikosaponin B2, quercetin, myricetin, caffeic acid, psoralidin, isobavachalcone, and lectins such as griffithsin. Other compounds such as lycorine may be suitable if a therapeutic level of antiviral activity can be achieved without exceeding toxic plasma concentrations. It was noted that the most promising small molecules identified as coronavirus inhibitors contained a conjugated fused ring structure with the majority being classified as being polyphenols.

Comparative label-free mass spectrometric analysis of temporal changes in the skeletal muscle proteome after impact trauma in rats.

Proteomics offers the opportunity to identify and quantify many proteins and to explore how they correlate and interact with each other in biological networks. This study aimed to characterize changes in the muscle proteome during the destruction, repair, and early-remodeling phases after impact trauma in male Wistar rats. Muscle tissue was collected from uninjured control rats and rats that were euthanized between 6 h and 14 days after impact injury. Muscle tissue was analyzed using unbiased, data-independent acquisition LC-MS/MS. We identified 770 reviewed proteins in the muscle tissue, 296 of which were differentially abundant between the control and injury groups (P ≤ 0.05). Around 50 proteins showed large differences (≥10-fold) or a distinct pattern of abundance after injury. These included proteins that have not been identified previously in injured muscle, such as ferritin light chain 1, fibrinogen γ-chain, fibrinogen ß-chain, osteolectin, murinoglobulin-1, T-kininogen 2, calcium-regulated heat-stable protein 1, macrophage-capping protein, retinoid-inducible serine carboxypeptidase, ADP-ribosylation factor 4, Thy-1 membrane glycoprotein, and ADP-ribosylation factor-like protein 1. Some proteins increased between 6 h and 14 days, whereas other proteins increased in a more delayed pattern at 7 days after injury. Bioinformatic analysis revealed that various biological processes, including regulation of blood coagulation, fibrinolysis, regulation of wound healing, tissue regeneration, acute inflammatory response, and negative regulation of the immune effector process, were enriched in injured muscle tissue. This study advances the understanding of early muscle healing after muscle injury and lays a foundation for future mechanistic studies on interventions to treat muscle injury.

Oxidative stress in alzheimer's disease: A review on emergent natural polyphenolic therapeutics.

OBJECTIVES: The aim of this research was to review the literature on Alzheimer's disease (AD) with a focus on polyphenolics as antioxidant therapeutics. DESIGN: This review included a search of the literature up to and including September 2019 in PubMed and MEDLINE databases using search terms that included: Alzheimer's Disease, Aß peptide, tau, oxidative stress, redox, oxidation, therapeutic, antioxidant, natural therapy, polyphenol. Any review articles, case studies, research reports and articles in English were identified and subsequently interrogated. Citations within relevant articles were also examined for consideration in this review. RESULTS: Alzheimer's disease is a neurodegenerative disorder that is clinically characterised by the progressive deterioration of cognitive functions and drastic changes in behaviour and personality. Due to the significant presence of oxidative damage associated with abnormal Aß accumulation and neurofibrillary tangle deposition in AD patients' brains, antioxidant drug therapy has been investigated as potential AD treatment. In particular, naturally occurring compounds, such as plant polyphenols, have been suggested to have potential neuroprotective effects against AD due to their diverse array of physiological actions, which includes potent antioxidant effects. CONCLUSIONS: The impact of oxidative stress and various mechanisms of pathogenesis in AD pathophysiology was demonstrated along with the therapeutic potential of emergent antioxidant drugs to address such mechanism of oxidation.

Salivary Protein Panel to Diagnose Systolic Heart Failure.

Screening for systolic heart failure (SHF) has been problematic. Heart failure management guidelines suggest screening for structural heart disease and SHF prevention strategies should be a top priority. We developed a multi-protein biomarker panel using saliva as a diagnostic medium to discriminate SHF patients and healthy controls. We collected saliva samples from healthy controls (n = 88) and from SHF patients (n = 100). We developed enzyme linked immunosorbent assays to quantify three specific proteins/peptide (Kallikrein-1, Protein S100-A7, and Cathelicidin antimicrobial peptide) in saliva samples. The analytical and clinical performances and predictive value of the proteins were evaluated. The analytical performances of the immunoassays were all within acceptable analytical ranges. The multi-protein panel was able to significantly (p < 0.001) discriminate saliva samples collected from patients with SHF from controls. The multi-protein panel demonstrated good performance with an overall diagnostic accuracy of 81.6% (sensitivity of 79.2% and specificity of 85.7%) when distinguishing SHF patients from healthy individuals. In conclusion, we have developed immunoassays to measure the salivary concentrations of three proteins combined as a panel to accurately distinguish SHF patients from healthy controls. While this requires confirmation in larger cohorts, our findings suggest that this three-protein panel has the potential to be used as a biomarker for early detection of SHF.

Characterization of the Blister Fluid Proteome for Pediatric Burn Classification.

Blister fluid (BF) is a novel and viable research matrix for burn injury study, which can reflect both systemic and local microenvironmental responses. The protein abundance in BF from different burn severities were initially observed using a 2D SDS-PAGE approach. Subsequently, a quantitative data independent acquisition (DIA) method, SWATH, was employed to characterize the proteome of pediatric burn blister fluid. More than 600 proteins were quantitatively profiled in 87 BF samples from different pediatric burn patients. These data were correlated with clinically assessed burn depth and time until complete wound re-epithelialization through several different statistical analyses. Several proteins from these analyses exhibited significant abundance change between different burn depth or re-epithelialization groups, and can be considered as potential biomarker candidates. Further gene ontology (GO) enrichment analysis of the significant proteins revealed the most significant burn related biological processes (BP) that are altered with burn depth, including homeostasis and oxygen transport. However, for wounds with re-epithelialization times more or less than 21 days, the significant GO annotations were related to enzyme activity. This quantitative proteomics investigation of burn BF may enable objective classification of burn wound severity and assist with clinical decision-making. Data are available via ProteomeXchange with identifier PXD011102.

Molecular Aspects of Wound Healing and the Rise of Venous Leg Ulceration: Omics Approaches to Enhance Knowledge and Aid Diagnostic Discovery.

Chronic wounds, in particular venous leg ulcers (VLU), represent a substantial burden for economies, healthcare systems and societies worldwide. This burden is exacerbated by the recalcitrant nature of these wounds, despite best practice, evidence-based care, which substantially reduces the quality of life of patients. Furthermore, co-morbidities such as diabetes and cardiovascular disease within ageing populations further contribute to the increasing prevalence in developed countries. This review provides an overview of the literature concerning the cellular and molecular mechanisms of wound healing and aspects where this process fails, resulting in a chronic wound. VLU may arise from chronic venous disease, which presents with many clinical manifestations and can lead to a highly complex disease state. Efforts to comprehend this state using various omics based approaches have delivered some insight into the underlying biology of chronic wounds and revealed markers of differentiation at the genomic, transcriptomic, proteomic and metabolomic levels. Furthermore, this review outlines the array of analytical tools and approaches that have been utilised for capturing multivariate data at each of these molecular levels. Future developments in spatiotemporal analysis of wounds along with the integration of multiple omics datasets may provide much needed information on the key molecules that drive wound chronicity. Such biomarkers have the potential to be developed into clinically relevant diagnostic tools to aid in personalised wound management.

Mass spectrometry based data of the blister fluid proteome of paediatric burn patients.

The data presented here are associated with the article "The blister fluid proteome of paediatric burns" (Zang et al., 2016) [1]. Burn injury is a highly traumatic event for children. The degree of burn severity (superficial-, deep-, or full-thickness injury) often dictates the extent of later scar formation which may require long term surgical operation or skin grafting. The data were obtained by fractionating paediatric burn blister fluid samples, which were pooled according to burn depth and then analysed using data dependent acquisition LC-MS/MS. The data includes a table of all proteins identified, in which burn depth category they were found, the percentage sequence coverage for each protein and the number of high confidence peptide identifications for each protein. Further Gene Ontology enrichment analysis shows the significantly over-represented biological processes, molecular functions, and cellular components of the burn blister fluid proteome. In addition, tables include the proteins associated with the biological processes of "wound healing" and "response to stress" as examples of highly relevant processes that occur in burn wounds.

The blister fluid proteome of paediatric burns.

UNLABELLED: Burn injury is highly traumatic for paediatric patients, with the severity of the burn often dictating the extent of scar formation. The diagnosis of burn wound severity is largely determined by the attending clinician's experience. Thus, a greater understanding of the biochemistry at burn wound site environment and the biology of burns of different severities at an earlier stage may reduce the reliance on subjective diagnoses. In this study, blister fluid was collected from superficial thickness, deep-partial thickness, and full-thickness paediatric burn wounds. Samples were combined together based on burn depth classification and then subjected to four different fractionation methods followed by trypsin digestion. Peptides were analysed by liquid chromatography tandem mass spectrometry in order to measure the proteome of each fraction. In total, 811 individual proteins were identified, including 107, 84, and 146 proteins unique to superficial, deep-partial thickness and full-thickness burn wounds, respectively. The differences in the protein inventory and the associated gene ontologies represented within each burn depth category demonstrated that there are subtle, yet significant, variations in the biochemistry of burn wounds according to severity. Importantly, this study has produced the most comprehensive catalogue of proteins from the paediatric burn wound microenvironment to date. SIGNIFICANCE: To our knowledge, this study has been the first to comprehensively measure the paediatric burn blister fluid proteome and has provided insight into the proteomic response to burn injury. The study contributes to the knowledge of blister fluid biochemistry of burn injury and provides clinically relevant knowledge through the qualitative evaluation of biochemical differences between burns of different depths. A better understanding of the burn wound environment will ultimately assist with more accurate clinical decision making and improved wound healing and scar reduction procedures.

Pan-proteomics, a concept for unifying quantitative proteome measurements when comparing closely-related bacterial strains.

The comparison of proteomes between genetically heterogeneous bacterial strains may offer valuable insights into physiological diversity and function, particularly where such variation aids in the survival and virulence of clinically-relevant strains. However, reports of such comparisons frequently fail to account for underlying genetic variance. As a consequence, the current knowledge regarding bacterial physiological diversity at the protein level may be incomplete or inaccurate. To address this, greater consideration must be given to the impact of genetic heterogeneity on proteome comparisons. This may be possible through the use of pan-proteomics, an analytical concept that permits the ability to qualitatively and quantitatively compare the proteomes of genetically heterogeneous organisms. Limited examples of this emerging technology highlight currently unmet analytical challenges. In this article we define pan-proteomics, where its value lies in microbiology, and discuss the technical considerations critical to its successful execution and potential future application.

The biochemistry of blister fluid from pediatric burn injuries: proteomics and metabolomics aspects.

Burn injury is a prevalent and traumatic event for pediatric patients. At present, the diagnosis of burn injury severity is subjective and lacks a clinically relevant quantitative measure. This is due in part to a lack of knowledge surrounding the biochemistry of burn injuries and that of blister fluid. A more complete understanding of the blister fluid biochemistry may open new avenues for diagnostic and prognostic development. Burn insult induces a highly complex network of signaling processes and numerous changes within various biochemical systems, which can ultimately be examined using proteome and metabolome measurements. This review reports on the current understanding of burn wound biochemistry and outlines a technical approach for 'omics' profiling of blister fluid from burn wounds of differing severity.

Provisional Matrix Deposition in Hemostasis and Venous Insufficiency: Tissue Preconditioning for Nonhealing Venous Ulcers.

Significance: Chronic wounds represent a major burden on global healthcare systems and reduce the quality of life of those affected. Significant advances have been made in our understanding of the biochemistry of wound healing progression. However, knowledge regarding the specific molecular processes influencing chronic wound formation and persistence remains limited. Recent Advances: Generally, healing of acute wounds begins with hemostasis and the deposition of a plasma-derived provisional matrix into the wound. The deposition of plasma matrix proteins is known to occur around the microvasculature of the lower limb as a result of venous insufficiency. This appears to alter limb cutaneous tissue physiology and consequently drives the tissue into a 'preconditioned' state that negatively influences the response to wounding. Critical Issues: Processes, such as oxygen and nutrient suppression, edema, inflammatory cell trapping/extravasation, diffuse inflammation, and tissue necrosis are thought to contribute to the advent of a chronic wound. Healing of the wound then becomes difficult in the context of an internally injured limb. Thus, interventions and therapies for promoting healing of the limb is a growing area of interest. For venous ulcers, treatment using compression bandaging encourages venous return and improves healing processes within the limb, critically however, once treatment concludes ulcers often reoccur. Future Directions: Improved understanding of the composition and role of pericapillary matrix deposits in facilitating internal limb injury and subsequent development of chronic wounds will be critical for informing and enhancing current best practice therapies and preventative action in the wound care field.