Vertical integration of biochemistry and clinical medicine using a near-peer learning model.

Vertical integration has been extensively implemented across medical school curricula but has not been widely attempted in the field of biochemistry. We describe a novel curricular innovation in which a near-peer learning model was used to implement vertical integration in our medical school biochemistry course. Senior medical students developed and facilitated a case-based small group session for first year biochemistry students.

Anti-candidal activity of genetically engineered histatin variants with multiple functional domains.

The human bodily defense system includes a wide variety of innate antimicrobial proteins. Histatins are small molecular weight proteins produced by the human salivary glands that exhibit antifungal and antibacterial activities. While evolutionarily old salivary proteins such as mucins and proline-rich proteins contain large regions of tandem repeats, relatively young proteins like histatins do not contain such repeated domains.

An unusual glycoform of human salivary mucin MG2.

Since in a previous study we encountered a subject with an unusual split MG2 banding pattern, the aim of this study was to investigate the molecular basis of this observation. Submandibular/sublingual secretion was collected under resting and stimulated conditions and examined on Western blots probed with anti-MG2 antibodies or on gels stained with periodic acid-Schiff reagent. Genomic DNA was isolated and the N-, tandem repeat (TR), and C-terminal regions of MUC7 were amplified by PCR since MG2 is known to display a genetic polymorphism.

Influence of histatin 5 on Candida albicans mitochondrial protein expression assessed by quantitative mass spectrometry.

Individual aspects of the mode of action of histatin 5, a human salivary antifungal protein, have been partially elucidated, but the mechanism likely involves a complex set of events that have not been characterized. Previous evidence points toward histatin-induced alterations in mitochondrial function. The purpose of the present study was to verify and quantify changes in the mitochondrial proteome of Candida albicans treated with histatin 5.

Two-hybrid analysis of human salivary mucin MUC7 interactions.

MUC7 is a low molecular weight monomeric mucin secreted by submandibular, sublingual and minor salivary glands. This mucin has been implicated in the non-immune host defense system in the oral cavity since it binds and agglutinates a variety of oral microbes. To investigate interactions between this mucin and other secretory salivary proteins, a submandibular gland prey library was screened with baits encoding the N- and C-terminal regions of MUC7 in the yeast two-hybrid system.

Suppression of MUC1 synthesis downregulates expression of the epidermal growth factor receptor.

The transmembrane mucin, MUC1, is overexpressed on many human carcinoma cells, increasing their metastatic potential through decreased cell-cell and cell-matrix adhesion. These cellular changes are mediated both through the altered physical properties of the mucin itself and through the role of the MUC1 cytoplasmic domain as a signaling molecule. The epidermal growth factor receptor (EGFR) is also overexpressed in many cancers and both it and MUC1 constitute important therapeutic targets.

Patterns of secretion of mucins and non-mucin glycoproteins in human submandibular/sublingual secretion.

The present investigation has characterised the influence of gustatory stimulation and duration of stimulation on the secretion pattern of salivary mucins MG1 and MG2 and non-mucin glycoproteins in submandibular/sublingual secretion (SMSL). Resting SMSL was collected for three 2 min intervals and stimulated SMSL was collected for ten 1 min intervals from six healthy subjects. Flow rates and total protein were significantly different under the two conditions.

Electron microscopic immunogold localization of salivary mucins MG1 and MG2 in human submandibular and sublingual glands.

The human salivary mucins MG1 and MG2 are well characterized biochemically and functionally. However, there is disagreement regarding their cellular and glandular sources. The aim of this study was to define the localization and distribution of these two mucins in human salivary glands using a postembedding immunogold labeling method.

Interaction of human salivary mucin MG2, its recombinant N-terminal region and a synthetic peptide with Actinobacillus actinomycetemcomitans.

The antimicrobial properties of human salivary mucin MG2 against the periodontal pathogen, Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), were investigated using purified MG2, rNMUC7 (a recombinant polypeptide containing residue 1-144 of MG2) and synthetic peptides PEP1 (residue 1-17) and PEP2 (residue 47-63). MG2 and rNMUC7 bound to A.

Structural characterisation of cysteines in a bacterial-binding motif of human salivary mucin MG2.

Human salivary mucin MG2 is a 180 kDa glycoprotein secreted by submandibular/sublingual and minor salivary glands. Secreted MG2 contains a domain with the only two cysteines (Cys(45) and Cys(50)) present in the polypeptide backbone; in native and recombinant MG2 this domain is involved in mucin binding to oral microbes. As the reduction and alkylation of MG2 has been shown to abolish binding, the present study was undertaken to determine whether the cysteine residues exist in the dithiol or disulphide form.

Expression of membrane-associated mucins MUC1 and MUC4 in major human salivary glands.

Mucins are high molecular weight glycoproteins secreted by salivary glands and epithelial cells lining the digestive, respiratory, and reproductive tracts. These glycoproteins, encoded in at least 13 distinct human genes, can be subdivided into gel-forming and membrane-associated forms. The gel-forming mucin MUC5B is secreted by mucous acinar cells in major and minor salivary glands, but little is known about the expression pattern of membrane-associated mucins.