A Comparative Study of the Antimicrobial and Structural Properties of Short Peptides and Lipopeptides Containing a Repetitive Motif KLFK.

Background: In the last years, Antimicrobial Peptides (AMPs) and lipopeptides have received attention as promising candidates to treat infections caused by resistant microorganisms.

Objective: The main objective of this study was to investigate the effect of repetitive KLFK motifs and the attachment of aliphatic acids to the N-terminus of (KLFK)n peptides on therapeutic properties.

Methods: Minimal inhibitory concentration against Gram (+) and (-) bacteria and yeast of synthetic compounds were determined by broth microtiter dilution method, and the toxicity was evaluated by hemolysis assay.

Biological and structural effects of the conjugation of an antimicrobial decapeptide with saturated, unsaturated, methoxylated and branched fatty acids.

The increasing bacterial resistance against conventional antibiotics has led to the search for new antimicrobial drugs with different modes of action. Cationic antimicrobial peptides (AMPs) and lipopeptides are promising candidates to treat infections because they act on bacterial membranes causing rapid destruction of sensitive bacteria. In this study, a decapeptide named A2 (IKQVKKLFKK) was conjugated at the N-terminus with saturated, unsaturated, methoxylated and methyl -branched fatty acids of different chain lengths (C8 - C20), the antimicrobial and structural properties of the lipopeptides being then investigated.

Characterization of individuals at high risk of developing melanoma in Latin America: bases for genetic counseling in melanoma.

Purpose: CDKN2A is the main high-risk melanoma-susceptibility gene, but it has been poorly assessed in Latin America. We sought to analyze CDKN2A and MC1R in patients from Latin America with familial and sporadic multiple primary melanoma (SMP) and compare the data with those for patients from Spain to establish bases for melanoma genetic counseling in Latin America.

Methods: CDKN2A and MC1R were sequenced in 186 Latin American patients from Argentina, Brazil, Chile, Mexico, and Uruguay, and in 904 Spanish patients.

Congenital agminated melanocytic nevus--case report.

Agminated nevus is a cluster group of melanocytic nevi confined to a localized area of the body. There are many pigmented lesions described in the literature as agminated, such as blue nevi, multiple lentigines and Spitz nevi, but only a few cases of congenital agminated melanocytic nevi have been described. We report a case of a male child who presented with congenital agminated nevi, emphasizing the importance of physical examination, dermoscopy, histopathological evaluation, differential diagnosis and follow up to rule out the possibility of dysplastic or malignant changes.

Interaction of acylated and substituted antimicrobial peptide analogs with phospholipid-polydiacetylene vesicles. Correlation with their biological properties.

A series of peptide analogs based on region 6-22 of Plantaricin 149 sequence were synthesized. The interaction between these analogs and phospholipid-polydiacetylene vesicles was investigated to evaluate the ability of the bioassay to detect differences in the interaction of the peptides with dipalmitoylphosphatidylglycerol and dipalmitoylphosphatidylcholine vesicles, associated with amino acid substitution and N-terminal conjugation of the sequences with short fatty acids (8 and 12 carbon atoms). Fatty acid conjugation of peptides with low antimicrobial activity resulted in lipopeptides with improved activity against strains of Staphylococcus aureus and Listeria monocytogenes.

[Evaluation of patients' learning about the ABCD rule: A randomized study in southern Brazil].

Background: the ABCD rule is used to guide physicians, health care professionals and patients to recognize the main characteristics of suspicious skin lesions for melanoma. In Brazil there are no studies to validate the use of the ABCD rule by patients after instructions given by dermatologists.

Objectives: to evaluate the learning of the ABCD rule by patients at a dermatology center of reference in the Southern region of Brazil.