Nanoencapsulated hypericin in P-123 associated with photodynamic therapy for the treatment of dermatophytosis.

The antifungal application of photodynamic therapy (PDT) has been widely explored. According to superficial nature of tinea capitis and the facility of application of light sources, the use of nanoencapsulated hypericin in P-123 associated with PDT (P123-Hy-PDT) has been a poweful tool to treat this pathology. Thus, the aim of this study was to evaluate the efficiency of P123-Hy-PDT against planktonic cells and in a murine model of dermatophytosis caused by Microsporum canis. In vitro antifungal susceptibility and in vivo efficiency tests were performed, including a skin toxicity assay, analysis of clinical signs by evaluating score, and photoacoustic spectroscopy. In addition, tissue analyses by histopathology and levels of pro-inflammatory cytokines, such as quantitative and qualitative antifungal assays, were employed. The in vitro assays demonstrated antifungal susceptibility with 6.25 and 12.5 µmol/L P123-Hy-PDI; these experiments are the first that have used this treatment of animals. P123-Hyp-mediated PDT showed neither skin nor biochemical alteration in vivo; it was safe for dermatophytosis treatment. Additionally, the treatment revealed rapid improvement in clinical signs at the site of infection after only three treatment sessions, with a clinical score confirmed by photoacoustic spectroscopy. The mycological reduction occurred after six treatment sessions, with a statistically significant decrease compared with untreated infected animals. These findings showed that P123-Hy-PDT restored tissue damage caused by infection, a phenomenon confirmed by histopathological analysis and proinflammatory cytokine levels. Our results reveal for the first time that P123-Hy-PDT is a promising treatment for tinea capitis and tinea corporis caused by M. canis, because it showed rapid clinical improvement and mycological reduction without causing toxicity.

Exploring the breakdown of dairy protein gels during in vitro gastric digestion using time-lapse synchrotron deep-UV fluorescence microscopy.

A novel time-lapse synchrotron deep-UV microscopy methodology was developed that made use of the natural tryptophan fluorescence of proteins. It enabled the monitoring in situ of the microstructural changes of protein gels during simulated gastric digestion. Two dairy gels with an identical composition, but differing by the coagulation mode, were submitted to static in vitro gastric digestion. The kinetics of gel particle breakdown were quantified by image analysis and physico-chemical analyses of digesta. The results confirm the tendency of rennet gels, but not acid gels, to form compact protein aggregates under acidic conditions of the stomach. Consequently, the kinetics of proteolysis were much slower for the rennet gel, confirming the hypothesis of a reduced pepsin accessibility to its substrate. The particle shapes remained unchanged and the disintegration kinetics followed an exponential trend, suggesting that erosion was the predominant mechanism of the enzymatic breakdown of dairy gels in these experimental conditions.

Investigation of the aroma of commercial peach (Prunus persica L. Batsch) types by Proton Transfer Reaction-Mass Spectrometry (PTR-MS) and sensory analysis.

The aim of this study was to investigate the aroma and sensory profiles of various types of peaches (Prunus persica L. Batsch.). Forty-three commercial cultivars comprising peaches, flat peaches, nectarines, and canning peaches (pavías) were grown over two consecutive harvest years. Fruits were assessed for chemical aroma and sensory profiles. Chemical aroma profile was obtained by proton transfer reaction-mass spectrometry (PTR-MS) and spectral masses were tentatively identified with PTR-Time of Flight-MS (PTR-Tof-MS). Sensory analysis was performed at commercial maturity considering seven aroma/flavor attributes. The four types of peaches showed both distinct chemical aroma and sensory profiles. Flat peaches and canning peaches showed most distinct patterns according to discriminant analysis. The sensory data were related to the volatile compounds by partial least square regression. γ-Hexalactone, γ-octalactone, hotrienol, acetic acid and ethyl acetate correlated positively, and benzeneacetaldehyde, trimethylbenzene and acetaldehyde negatively to the intensities of aroma and ripe fruit sensory scores.