Immunoinformatics-based characterization of immunogenic CD8 T-cell epitopes for a broad-spectrum cell-mediated immunity against high-risk human papillomavirus infection.

Human papillomavirus (HPV) represents the most prevalent sexually transmitted infectious agent worldwide. Vaccination has been an approach successfully used as a prophylactic measure against this infectious agent in patients without previous contact with the genotypes present in the vaccine. In this work, we use a computational approach to predict CD8 T cell epitopes from HPV proteins to promote cell-mediated immunity. We evaluated immunogenicity, conservation, toxicity, stability and population coverage of epitopes. Finally, a molecular docking analysis was performed to confirm the stability of the complexes formed. We identified 17 epitopes with affinity for several HLA alleles, covering 5 binding supermotifs (A2, A3, A24, B62 and B57). The analyses showed that these epitopes have a high population coverage and are highly conserved among several HPV genotypes. Seven of them (NWKNFFSTTWE1594-603, KVSAFQYRVFRVL163-74, LQFIFQLCKL1372-380, RVFRVQLPDPNKL170-81, FNKPYWLHRL1307-315, FITCVDTTRL1330-338 and HLRREQIFARL1248-257) were 100% conserved. Finally, molecular docking confirmed the stability of the complexes by means of a large network of hydrogen bonds formed and the calculated low bonding energy. The epitopes identified in this study are potential candidates as components of therapeutic vaccines and we suggest that these epitopes can be used in future studies aiming to activate antigen-specific CD8 T cells.

Design of a bioinspired cable driven actuator with clutched elastic elements for the ankle.

Bioinspiration can be used to improve the efficiency of these assistive biomechatronic devices. In this paper, a cable driven actuator for the human ankle was designed using a bioinspired approach. The torque reduction was achieved by means of force amplifying elements such as cables with pulley, and, to reduce the power requirements for the motor, the actuator mimics a muscle using a clutched parallel elastic element. The simulations to validate the model were performed using real gait data and the results prove the viability of the device to be used in anthropomorphic legs and exoskeletons. Although the losses due to friction were not considered, the simulations showed a reduction of 60% in the force peak and 40% in the power peak.

Polyphenolic compounds with biological activity in guabiroba fruits (Campomanesia xanthocarpa Berg.) by comprehensive two-dimensional liquid chromatography.

This study aimed to evaluate the polyphenolic composition along with the biological activity of guabiroba (Campomanesia xanthocarpa Berg.) fruits using comprehensive two-dimensional liquid chromatography (LC × LC). A simplex centroid design comprising three solvents (methanol, 2% acetic acid, and acetonitrile) was used to optimize the extraction mixture for polyphenols from ripe and unripe guabiroba fruits. A quantitative LC × LC platform was proposed to characterize the guabiroba extracts using a RP-Amide column and a C18 column in the first and second dimensions, respectively. Antidiabetic properties, using in vitro enzyme assay models and in vivo antioxidant activity with the eukaryote model Saccharomyces cerevisiae, was measured. Total phenolics compounds were more efficiently extracted with 2% acetic acid solution and acetonitrile (50:50, v/v). A total of 37 different compounds were identified and quantified using the proposed LC × LC method (linearity ranging from 0.9990 to 0.9994, intra- and interday precision from 0.40 to 10.57% and, accuracy from 81.89 to 108.98%). Significant differences were observed between ripe and unripe guabiroba fruits, especially for the compounds geraldone and methyl galangin isomer. Guabiroba fruits showed significant antidiabetic and antioxidant properties and may be potentially adopted as part of dietary strategies in the management of early stages of type 2 diabetes and associated complications.