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Tissue-engineered oral mucosal equivalents have been developed for in vitro studies for a few years now. However, the usefulness of currently available models is still limited by many factors, mainly the lack of a physiological extracellular matrix (ECM) and the use of cell populations that do not reflect the properly differentiated cytotypes of the mucosa of the oral cavity. For this reason, we have developed a novel three-dimensional culture model reflecting the normal architecture of the human oral mucosa, with the main aim of creating a better in vitro model where to test cellular responses to drugs administration. This novel 3D cell culture model (3D outgrowth) was set up using an artificial extracellular matrix (Matrigel™ ), allowing the interactions required for proper differentiation of the various citotypes which form the mucosal layer. Biopsies of human oral mucosa, in fragments of about 0.5 mm3, were placed onto 6.5mm Transwells, covered with Matrigel™ and grown in a specific culture medium. A gradual formation of an architectural structure similar to that of the in vivo oral mucosa was observed. Transmission electron and confocal microscopy were employed to characterize the newly developed model: the cell components (keratinocytes and fibroblasts) differentiated properly within the outgrowth and reconstituted, in vitro, the physiological structure of the human oral mucosa, including a stratified non-keratinized squamous layer composed of four different layers, a proper basal membrane and a lamina propria where fibroblasts produce ECM. Moreover, keratinocytes expressed CK5, CK13, CK19 and E-cadherin, whereas fibroblasts expressed collagen type I and IV, laminin and fibronectin. 3D outgrowths could be considered a valid alternative to animal models, and provide useful information for researchers interested in studying the responses of the human oral mucosa to locally delivered drugs or other exogenous treatments.

Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting sideeffects, the design of formulations for local application on malignant lesions seems to be an efficient and promising drug delivery approach. In this study, the effect of locally applied 5-FU on cell death was evaluated both in a SCC4/HEK001 model and in a newly proposed 3D outgrowth model of oral squamous cell carcinoma (OSCC). Initially, the optimal drug dose was established by delivery of solutions containing different amounts of 5-FU. The solution containing 1 (w/v) of 5-FU resulted effective in inducing cell death with complete eradication of cell colonies. Buccal tablets were designed to deliver 5-FU locoregionally to the cancer lesions of the oral cavity. Tablets were prepared using a drug loaded matrix of acrylic/methacrylic acid copolymer containing 1 (w/w) of 5-FU and applied on 3D outgrowths. The drug release from tablets appeared to be sufficient to induce cell death as confirmed by transmission electron microscopy and enzymatic assay (TUNEL). After 120 h of treatment, when about 90 of the drug had been discharged from the tablets into the culture environment, 5-FU caused loss of cell-cell communications and apoptotic cell death. After 192 h, a complete disaggregation of the 3D oral outgrowths and the death of all the cells was observed. Buccal matrix tablets could be considered a promising new approach to the locoregional treatment of OSCC. Risks of systemic toxicity are avoided since very low drug doses are delivered.

We investigated cues that mediate the aggregation behavior of immature pentatomid bugs by using nymphs of six different pentatomid bug species (Nezara viridula, Acrosternum hilare, Chlorochroa ligata, Chlorochroa sayi, Thyanta pallidovirens, and Euschistus conspersus). When first instars of any two species were put together in a Petri dish, they readily formed heterospecific aggregations similar to their natural conspecific aggregations. The chemical profiles of first and second instar nymphs of each species were determined by solvent extraction with pentane, followed by GC–MS analysis. Immature bugs of the different species had some compounds in common, and some that were more species specific. Within a species, there were distinct differences in the profiles of compounds extracted from first and second instars. Bugs did not aggregate around untreated polysulfone beads (1 mm diam) that were glued together in groups approximating bug egg masses, suggesting that tactile cues alone were insufficient to induce aggregation. Furthermore, when tested over a range of doses, groups of polysulfone beads treated with crude whole-body extracts of bugs did not induce or maintain aggregations. However, first instar N. viridulanymphs did respond to beads treated with two of the three major components of bug extracts. 4-Oxo-(E)-2-decenal induced significant aggregations at two doses, whereas tridecane, the major component in extracts from all six species, did not, and (E)-2-decenal was repellent. The repellence of (E)-2-decenal may explain why we and previous researchers were unable to induce aggregations of first instar N. viridulausing whole-body extracts.

A few authors have published articles on unusual cases of internal hernias; however, there are no reports in the literature of a hernia arising from a right-sided retroperitoneal defect resulting in the incarceration of small bowel in Morison’s pouch. This case illustrates how point-of-care ultrasound was used to diagnose a small bowel obstruction in an atypical location.