The cytotoxic effect of the tetrameric peptide LfcinB (20–25) ₄ against breast cancer cell line ATCC® HTB-22™ (MCF-7) was evaluated.

The cytotoxic effect against the breast cancer cell line MDA-MB-468 of the palindromic peptide LfcinB (21–25) _Pal : ¹ RWQWRWQWR ⁹ and its analogous peptides, obtained via alanine scanning, was evaluated.

The aim of this study was to characterise and analyse articles published on resilience and old-age from 1990-2006. After a systematic search of five databases (Academic Search Premier-Ebsco Host, Medline, Psyc Articles, Ovid and Science Direct) 33 pieces of literature were included in the analysis. The selected articles had 31 different definitions of resilience, from eight disciplines, mainly health-related fields. It was also found that the research studied the association of resilience with individual (68 variables) and social/environmental factors (17 variables); the most frequent were age and health self-perception. Cultural and religious values were of special interest amongst the latter variables. The literature review demonstrated that resilience in old age is a topic having increasing research interest; this has been linked to various individual, social and cultural factors. However, this is a rapidly developing area that requires that a unified definition be established and that a theoretical and intervention model be created.

The effect on the cytotoxicity against breast cancer cell lines of the substitution of ²⁶Met residue in the sequence of the Bovine Lactoferricin-derived dimeric peptide LfcinB (20-30)₂: (²⁰RRWQWRMKKLG³⁰)₂-K-Ahx with amino acids of different polarity was evaluated. The process of the synthesis of the LfcinB (20-30)₂ analog peptides was similar to the original peptide. The cytotoxic assays showed that some analog peptides exhibited a significant cytotoxic effect against breast cancer cell lines HTB-132 and MCF-7, suggesting that the substitution of the Met with amino acids of a hydrophobic nature drastically enhances its cytotoxicity against HTB-132 and MCF-7 cells, reaching IC₅₀ values up to 6 µM. In addition, these peptides have a selective effect, since they exhibit a lower cytotoxic effect on the non-tumorigenic cell line MCF-12. Interestingly, the cytotoxic effect is fast (90 min) and is maintained for up to 48 h. Additionally, through flow cytometry, it was found that the obtained dimeric peptides generate cell death through the apoptosis pathway and do not compromise the integrity of the cytoplasmic membrane, and there are intrinsic apoptotic events involved. These results show that the obtained peptides are extremely promising molecules for the future development of drugs for use against breast cancer.

The purpose of this article is to describe the process of the development of the “Resilience Theoretical Analysis Matrix” (RTAM) (or in its Spanish translation: MATR), a tool designed to facilitate a coherent and organised approach to the assessment of a wide spectrum of factors influencing the development of resilience in the face of disability, old age and poverty, and the relationships among these factors. The matrix‐building process occurred in four phases: (1) research and synthesis from three theoretical sources; (2) a comparative analysis of the theoretical sources and the generation of the matrix dimensions for the first version of the RTAM; (3) the re‐arrangement of the dimensions according to the principles of cultural psychology; and (4) the generation of the RTAM (Final Version). The process resulted in a matrix including six processes ranging from structural processes to individual processes, and whose horizontal or transversal axes are subjectivity, the relational perspective and the historical–cultural perspective. Despite being a theoretical tool, the matrix constitutes a contribution to the applied fields of health and social welfare. Its use in real cases can inform health and social service providers about the psychological, social, political and cultural factors that should be strengthened to promote resilience. In turn, this will contribute to building, maintaining and restoring the health and quality of life for older people with disabilities who live in poverty.