Enzymatically-controlled biomimetic synthesis of titania/protein hybrid thin films.

Although it is widely recognised that enzymes play a significant role in sculpting complex silica skeletons in marine sponges, the potential for exploiting enzymes in materials synthesis has not yet been fully harnessed. In this work we show that the digestive enzyme papain can self-assemble into monolayers on oxide surfaces, where they then drive the formation of crystalline titanium dioxide nanoparticles. This dual functionality of thin film formation and mineralization promotion has the potential to enable the construction of hierarchical inorganic/organic structures in the form of continuous amorphous titania/protein films which can be refined to 93% anatase post annealing. Additional control over the film thickness is afforded by layer-by-layer processing using a simple dip-coating approach. Papain's TiO2-mineralizing activity displays complex kinetics that deviates from the native Michaelis-Menten kinetic activity, yet deactivation studies demonstrate that this activity relies upon residues that are essential for catalytic site function. These parameters provide unique insight into enzymatic biomineralization, allowing a flexible route to achieving bioengineered titania heterostructures, and potentially providing a green-chemistry solution to photovoltaic cell development.

Enhancing the immunogenicity of tumour lysate-loaded dendritic cell vaccines by conjugation to virus-like particles.

BACKGROUND: Tumour cell lysates are an excellent source of many defined and undefined tumour antigens and have been used clinically in immunotherapeutic regimes but with limited success. METHODS: We conjugated Mel888 melanoma lysates to rabbit haemorrhagic disease virus virus-like particles (VLP), which can act as vehicles to deliver multiple tumour epitopes to dendritic cells (DC) to effectively activate antitumour responses. RESULTS: Virus-like particles did not stimulate the phenotypic maturation of DC although, the conjugation of lysates to VLP (VLP-lysate) did overcome lysate-induced suppression of DC activation. Lysate-conjugated VLP enhanced delivery of antigenic proteins to DC, while the co-delivery of VLP-lysates with OK432 resulted in cross-priming of naïve T cells, with expansion of a MART1(+) population of CD8(+) T cells and generation of a specific cytotoxic response against Mel888 tumour cell targets. The responses generated with VLP-lysate and OK432 were superior to those stimulated by unconjugated lysate with OK432. CONCLUSION: Collectively, these results show that the combination of VLP-lysate with OK432 delivered to DC overcomes the suppressive effects of lysates, and enables priming of naïve T cells with superior ability to specifically kill their target tumour cells.

Swallow syncope.

Swallowing is considered a rare cause of syncope. The five patients described in this report had a spectrum of gastrointestinal tract or cardiovascular disease. For each patient there was a clear association between swallowing and the onset of syncope. Prompt diagnosis of this potentially lethal condition is essential, and electrocardiographic monitoring during swallowing is advisable in all cases in which syncope is suspected.

The effect of a televised periodontal campaign on public periodontal awareness.

The purpose of this investigation was to evaluate the impact of the Minnesota Dental Association's 1979 to 1980 periodontal awareness television campaign in terms of (1) reaching the target population, (2) improving public knowledge regarding the major reason for tooth loss in adults and (3) increasing intended future preventive dental visits. Based on the Health Belief Model, a 30-second television message was developed presenting periodontal disease as an often overlooked but compelling reason to seek preventive dental care. The message was aimed at adults 18 years of age and older who did not visit the dentist regularly. It was broadcast 1280 times over two separate 6-week periods on 17 statewide television stations. A postcampaign personal interview of a representative cross section of 1,000 Minnesota adults indicated that the campaign reached 79% of the population surveyed, or 786 individuals. Eighty-two percent (534) of the 654 individuals who made regular dental visits and 73% (252) of the 346 individuals who did not, indicated exposure to the message. Of the 786 persons who viewed the message, 90% (707) correctly recalled the message content. Seventy-five percent (488) of the 654 individuals who made regular dental visits and 63% (219) of the 346 individuals who did not, correctly recalled the message content. As a result of exposure to the television campaign, 10% (76) of the 786 viewers indicated their intention to make more preventive dental visits in the future. Among individuals stating such an intention were 10% (71) of the 707 viewers who correctly recalled the message and six percent (5) of the 79 viewers who were not able to correctly recall the message content.