Publications by authors named "Cruchley A"

Oral healthcare products are well tolerated and while adverse occurrences are rare there is still a need to explore the interaction between these products and the oral mucosa. This study assessed the effects of oral healthcare ingredients: sodium lauryl sulphate (SLS), a detergent; cinnamic aldehyde (CA), a flavouring agent; and cetylpyridinium chloride (CPC), an antiseptic, using a reconstructed human oral mucosal model (OMM). Differential release of inflammatory cytokines IL-1α, IL-8 and cytotoxicity was compared with other known irritants and sensitizers to identify a signature response profile that could be associated with oral mucosal irritation.

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Objective: To develop polymeric hydrogel delivery systems for iontophorseis transfer of large molecules across buccal (porcine) mucosa.

Methods: Three hydrogels (PVA, HPMC and PVA/HPMC) were prepared as stable gels (7 mm diameter/1.5 mm thick).

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Objective: To investigate the feasibility of iontophoretic delivery of large molecules across buccal mucosa, and to establish its potential for enhanced drug delivery.

Methods: Qualitative (6h) and quantitative (8 and 36 h) assessment of porcine buccal mucosa, using a diffusion cell in vitro model, was carried out by fluorescent microscopy and UV/Vis spectroscopy respectively, with four fluorescently-labeled model species (3 and 10 kDa dextrans, 12 kDa parvalbumin and 66 kDa bovine serum albumin, BSA). Passive and iontophoresis parameters were obtained.

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Epstein-Barr virus (EBV) replicates in superficial differentiated cells of oral hairy leukoplakia (OHL). Differentiation of squamous epithelial cells depends on B-lymphocyte-induced maturation protein 1 (Blimp1). Here we show that expression of the EBV immediate-early protein BZLF1 is restricted to Blimp1-positive epithelial cells in OHL.

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Candida albicans is a commensal organism at several sites and is a versatile, opportunistic pathogen. The underlying factors of pathogen and host associated with commensalism and pathogenicity in C. albicans are complex and their importance is largely unknown.

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Porphyromonas gingivalis is a major bacterial species implicated in chornic periodontitis, a disease characterized by inflammatory destruction of the tooth supporting tissues. Its main virulence factors are lipopolysaccharide (LPS) and gingipains, a group of cysteine proteinases. Interleukin (IL)-18 is a potent pro-inflammatory cytokine with structural similarities to IL-1beta.

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Background: Oral submucous fibrosis (OSF) is a high-risk pre-cancerous condition where 7-13% of these patients develop head and neck squamous cell carcinoma (HNSCC). To date there is no cancer predictive markers for OSF patients. Genomic instability hallmarks early genetic events during malignant transformation causing loss of heterozygosity (LOH) and chromosomal copy number abnormality.

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Background: Oral submucous fibrosis (OSF) is a precancerous condition showing extensive fibrosis of the submucosa and affects most parts of the oral cavity, including pharynx and upper third of the oesophagus. The molecules involved in the biological pathways of the fibrotic process appeared to be either down- or upregulated at different stages of the disease. Despite the precancerous nature, malignant transformation of the epithelium in the background of fibrosis has not been studied in detail.

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Oral submucous fibrosis (OSF) is characterized by abnormal collagen metabolism in the submucosal connective tissue. Its influence on the overlying epithelium is not known but about 14% of OSF cases undergo malignant transformation to squamous cell carcinoma indicating association with abnormality of the epithelium. Here, we have defined the keratin expression profile, by immunohistochemistry and quantitative image analysis, using a panel of 22 anti-keratin monoclonal antibodies on 28 OSF samples.

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Adrenomedullin is a multifunctional peptide produced by a wide range of different cells and tissues. This study was designed to investigate whether adrenomedullin is present in human saliva and in salivary glands. It was expected that saliva may contain high concentrations of adrenomedullin, which has antimicrobial activity in vitro, which may have functional implications in the oral cavity.

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Objectives: The aim of this study was to evaluate the effect of short-term exposure to ethanol on the permeability barrier properties of human oral mucosa.

Materials And Methods: Permeability constants (Kp x 10(-4) cm min(-1)) to tritiated water were determined, for untreated human ventral tongue, and following treatment with phosphate-buffered saline (PBS), 5, 15 or 40% ethanol using an in vitro perfusion chamber system. Some samples were also exposed to fluorescent-labelled albumin and examined by fluorescence microscopy.

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The desmosomal cadherin desmocollin (Dsc)1 is expressed in upper epidermis where strong adhesion is required. To investigate its role in vivo, we have genetically engineered mice with a targeted disruption in the Dsc1 gene. Soon after birth, null mice exhibit flaky skin and a striking punctate epidermal barrier defect.

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Objectives: The aim of this study was to establish whether an in vitro model of human oral mucosa had similar permeability characteristics to normal oral mucosa. Such a model would have considerable value as an alternative to the use of mucosal biopsies in studies of transmucosal drug delivery.

Materials And Methods: Keratinocytes obtained from buccal mucosa, hard palate and abdominal skin were seeded onto inert collagen membranes (Cellagen Discs) or dead de-epidermised dermis (DDED) and grown either as submerged or air-liquid interface cultures.

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Oral candidal infections are often persistent and intractable and thus the aim of this study was to develop a polymeric sustained release device to improve the topical treatment of these infections. A self curing system based on poly(ethyl methacrylate) and tetrahydrofurfuryl methacrylate (PEM/THFM) was used with chlorhexidine diacetate (CX) added at levels between 0 and 12% w/w. Water uptake by the device was assessed gravimetrically and CX release measured by UV spectrometry.

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The release of recombinant human bone morphogenetic protein-2 (rhBMP-2) from three room temperature polymerising methacrylate systems has been studied. These all contained poly(ethyl methacrylate) powder, but the monomer liquids comprised, respectively, tetrahydrofurfuryl methacrylate (THFM), 90/10 THFM/hydroxyethyl methacrylate (HEMA), and 70/30 THFM/ HEMA. In all cases, rhBMP-2 was released, but the addition of 10% HEMA accelerated release (a nine-fold increase in diffusion coefficient); a further increase to 30% HEMA had no additional effect.

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Objective: Sodium lauryl sulphate (SLS), an important component in many oral health products, is well established as a contact irritant in skin. Recent studies have suggested that it may also affect the structural integrity of oral mucosa. SLS is rarely used alone in dentifrices or mouthwashes and the aim of this study was to establish the effect of SLS both alone and in combination with Triclosan (TCN) and zinc (Zn) on the permeability barrier properties of normal human oral mucosa.

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Background: The protease-activated receptor-2 (PAR-2) is expressed by vascular endothelial cells and upregulated by lipopolysaccharide (LPS) in vitro. PAR-2 is activated by a tethered ligand created after proteolytic cleavage by trypsin or experimentally by a synthetic agonist peptide (PAR-2AP) corresponding to the new amino terminus of the tethered ligand.

Methods And Results: Intravenous administration of PAR-2AP (0.

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We previously demonstrated the presence of adrenomedullin receptors in the rat adrenal cortex. There is evidence, however, that the actions of adrenomedullin may also be mediated by the CGRP receptor. The present study was designed to determine whether specific CGRP receptors are present in the rat adrenal cortex.

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Vascular endothelial growth factor (VEGF) is a multifunctional angiogenic cytokine of importance in inflammation and wound healing but its presence in chronic inflammatory periodontal disease has never been reported. The aims of this study were to investigate the presence of VEGF in human periodontal tissue and gingival crevicular fluid (GCF) in periodontal health and disease. VEGF in tissue was localized by immunohistochemistry.

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While the presence of neuropeptide Y (NPY) in the adrenal cortex is well established, little is known about its regulation. In the present study the involvement of the pituitary gland in the regulation of rat adrenal NPY content was investigated. Rats were subjected to one of the following treatments: hypophysectomy, sham operation, ACTH, the synthetic glucocorticoid, dexamethasone, dexamethasone plus ACTH, or saline control.

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The protease-activated receptor-2 (PAR-2) is a seven transmembrane domain receptor related to the thrombin receptor, which is activated in vitro by cleavage by trypsin. Affinity-purified rabbit IgG raised against a peptide corresponding to the trypsin cleavage site of PAR-2 was used for an immunohistochemical study of skin. The expression of PAR-2 in epidermis was striking, with keratinocytes showing abundant intercellular and cytoplasmic staining.

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Saliva is an enriched milieu containing biologically active proteins, including several different growth factors and cytokines. This study documents that vascular endothelial growth factor (VEGF), a potent, multifunctional, angiogenic cytokine, is a component of normal human saliva. VEGF was measured by ELISA in whole saliva (median concentration, 460 pg/ml) and in ductal secretions obtained from the parotid (277 pg/ml) and the submandibular-sublingual (80 pg/ml) salivary glands.

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Objectives: Oral hairy leukoplakia (HL) is an acanthotic, hyperparakeratotic lesion characterised by the presence of a replicative Epstein-Barr virus (EBV) infection in the superficial and adjoining layers of the epithelium. EBV or its gene products are capable of modifying epithelial differentiation. The aim of this study was to establish whether the presence of EBV was associated with an alteration in cell turnover by assessing bromodeoxyuridine (BrdU) incorporation and Ki 67 expression in lesional tissue and control mucosa.

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The aim of this study was to assess the cell proliferation in ameloblastomas and to correlate this with clinical features and histology. Immunohistochemistry with Ki-67 monoclonal antibody was performed on fresh tissue from 54 ameloblastomas. A labelling index (LI) was calculated by expressing the percentage of Ki-67 positive cells.

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Vascular endothelial growth factor (VEGF) is a multifunctional cytokine that plays a pivotal role in mediating neovascularization as well as other endothelial cell alterations during inflammation. In this study, we demonstrate that human neutrophils are a source of VEGF. We observed that isolated blood neutrophils released VEGF in response to different stimuli and we demonstrated by immunohistochemistry that neutrophils infiltrating inflamed tissues contain VEGF.

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