There is a growing level of interest in the potential role inflammation has on the initiation and progression of malignancy. Notable examples include Helicobacter pylori-mediated inflammation in gastric cancer and more recently Fusobacterium nucleatum-mediated inflammation in colorectal cancer. Fusobacterium nucleatum is a Gram-negative anaerobic bacterium that was first isolated from the oral cavity and identified as a periodontal pathogen. Biofilms on oral squamous cell carcinomas are enriched with anaerobic periodontal pathogens, including F. nucleatum, which has prompted hypotheses that this bacterium could contribute to oral cancer development. Recent studies have demonstrated that F. nucleatum can promote cancer by several mechanisms; activation of cell proliferation, promotion of cellular invasion, induction of chronic inflammation and immune evasion. This review provides an update on the association between F. nucleatum and oral carcinogenesis, and provides insights into the possible mechanisms underlying it.
Chronic obstructive pulmonary disease (COPD) is a debilitating heterogeneous disease characterised by unregulated proteolytic destruction of lung tissue mediated via a protease-antiprotease imbalance. In COPD, the relationship between the neutrophil serine protease, neutrophil elastase, and its endogenous inhibitor, alpha-1-antitrypsin (AAT) is the best characterised. AAT belongs to a superfamily of serine protease inhibitors known as serpins. Advances in screening technologies have, however, resulted in many members of the serpin superfamily being identified as having differential expression across a multitude of chronic lung diseases compared to healthy individuals. Serpins exhibit a unique suicide-substrate mechanism of inhibition during which they undergo a dramatic conformational change to a more stable form. A limitation is that this also renders them susceptible to disease-causing mutations. Identification of the extent of their physiological/pathological role in the airways would allow further expansion of knowledge regarding the complexity of protease regulation in the lung and may provide wider opportunity for their use as therapeutics to aid the management of COPD and other chronic airways diseases.
To create functional tissue engineering scaffolds, biomaterials should mimic the native extracellular matrix of the tissue to be regenerated. Simultaneously, the survival and functionality of stem cells should also be enhanced to promote tissue organisation and repair. Hydrogels, but in particular, peptide hydrogels, are an emerging class of biocompatible scaffolds which act as promising self-assembling biomaterials for tissue engineering and regenerative therapies, ranging from articular cartilage regeneration at joint defects, to regenerative spinal cord injury following trauma. To enhance hydrogel biocompatibility, it has become imperative to consider the native microenvironment of the site for regeneration, where the use of functionalised hydrogels with extracellular matrix adhesion motifs has become a novel, emerging theme. In this review, we will introduce hydrogels in the context of tissue engineering, provide insight into the complexity of the extracellular matrix, investigate specific adhesion motifs that have been used to generate functionalised hydrogels and outline their potential applications in a regenerative medicine setting. It is anticipated that by conducting this review, we will provide greater insight into functionalised hydrogels, which may help translate their use towards therapeutic roles.
Amongst the recognised classes of naturally occurring antimicrobials, human host defence peptides are an important group with an advantage (given their source) that they should be readily translatable to medicinal products. It is also plausible that truncated versions will display some of the biological activities of the parent peptide, with the benefit that they are less costly to synthesise using solid phase chemistry. The host defense peptide, LL-37, and two truncated mimetics, KE-18 and KR-12, were tested for their inhibitory effects and antibiofilm properties against Candida albicans, Staphylococcus aureus and Escherichia coli, microorganisms commonly implicated in biofilm-related infections such as ventilator associated pneumonia (VAP). Using in silico prediction tools, the truncated peptides KE-18 and KR-12 were selected for MIC and antibiofilm testing on the basis of their favourable cationicity, hydrophobic ratio and amphipathicity compared with the parent peptide. Two methods were analysed for determining peptide efficacy against biofilms; a crystal violet assay and an XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay. The biocidal activities measured by minimum inhibitory concentration (MIC) and antibiofilm activities (measured by a crystal violet assay) appeared to be independent. LL-37 had no biocidal action against C. albicans (MIC > 250 µg/ml) but significant effects in both biofilm prevention and biofilm inhibition assays. KE-18 and KR-12 yielded superior MIC values against all three microorganisms. Only KE-18 had a significant effect in the biofilm prevention assay, which persisted even at sub-MIC concentrations. Neither of the truncated peptides were active in the biofilm inhibition assay. KE-18 was shown to bind lipopolysaccharide (LPS) as effectively as LL-37 and to bind lipoteichoic acid (LTA) more effectively. None of the peptides showed haemolytic activity against human erythrocytes at the concentrations tested. KE-18 should be considered for further development as a natural peptide-derived therapeutic for prevention of multi-species biofilm-related infections such as VAP.
11 July 2013 in Journal of Clinical Periodontology
Background: The importance of good oral hygiene for patients in Intensive Care Units (ICUs) is well recognized, however, the most effective way to achieve good oral care in the ICU is unclear.Aim: This study aimed to provide a national picture of oral care practices in adult ICUs in the United Kingdom (UK) to identify areas for improvement.Study Design: A national one‐day point prevalence study was undertaken in adult ICUs in the UK in the period from 30th September to 14th October 2021. Data were collected on all patients in the ICU on the date of data collection. Using a validated electronic data collection form, anonymised data were collected on methods and frequency of oral care provided, and the use of oral care protocols within the ICU. Data were analysed using descriptive analysis.Results: Data from 195 patients in 15 ICUs in England, Wales and Northern Ireland were collected. Written oral care protocols were available for use in the care of 65% (n = 127) of patients. 73% (n = 142) of patients received oral care within the 24‐h period. Oral care methods included toothbrushing 41% (n = 79), foam sticks 3% (n = 5), moisturizing the oral cavity 10% (n = 19) and mouth rinse with chlorhexidine 3% (n = 5) and other oral care methods not specified 12% (n = 23). 44% (n = 85) of patients had an oral assessment within the 24‐h period and variable assessment methods were used.Conclusion: There is large variability in oral care provision and methods for intubated ICU patients and a lack of consensus was revealed in the study. Oral assessment is conducted less frequently using multiple tools. Optimal oral care standards and further research into oral care provision is pivotal to address this important patient‐relevant practice.Relevance to Clinical Practice: Oral care is a fundamental part of care for ICU patients, however, there is a large degree of variability, and oral care is often not based upon oral assessment. The use of an oral care protocol and oral assessments would help to improve patient care, ease of use for staff and provide a tailored oral care plan for patients, improving efficiency and preventing wasted resources.