Expanding the Database of Signal-Anchor-Release Domain Endolysins Through Metagenomics.

Endolysins are bacteriophage-derived lytic enzymes with antimicrobial activity. The action of endolysins against Gram-negative bacteria remains a challenge due to the physical protection of the outer membrane. However, recent research has demonstrated that signal-anchor-release (SAR) endolysins permeate the outer membrane of Gram-negative bacteria. This study investigates 2628 putative endolysin genes identified in 183,298 bacteriophage genomes. Previously, bioinformatic approaches resulted in a database of 66 SAR endolysins. This manuscript almost doubles the list with 53 additional SAR endolysin candidates. Forty-eight of the putative SAR endolysins described in this study contained one muramidase catalytic domain, and five included additional cell wall-binding domains at the C-terminus. For the moment, SAR domains are found in four protein families: glycoside hydrolase family 19 (GH19), glycoside hydrolase family 24 (GH24), glycoside hydrolase family 25 (GH25), and glycoside hydrolase family 108 (GH108). These SAR lysis are clustered in eight groups based on biochemical properties and domain presence/absence. Therefore, in this study, we expand the arsenal of endolysin candidates that might act against Gram-negative bacteria and develop a consult database for antimicrobial proteins derived from bacteriophages.

Antimicrobial Peptides and Nanotechnology, Recent Advances and Challenges.

Antimicrobial peptides are sequences of amino acids, which present activity against microorganisms. These peptides were discovered over 70 years ago, and are abundant in nature from soil bacteria, insects, amphibians to mammals and plants. They vary in amino acids number, the distance between amino acids within individual peptide structure, net charge, solubility and other physical chemical properties as well as differ in mechanism of action. These peptides may provide an alternative treatment to conventional antibiotics, which encounter resistance such as the peptide nisin applied in treating methicillin resistant Staphylococcus aureus (MRSA) or may behave synergistically with known antibiotics against parasites for instance, nisin Z when used in synergy with ampicillin reported better activity against Pseudomonas fluorescens than when the antibiotic was alone. AMPs are known to be active against viruses, bacteria, fungi and protozoans. Nanotechnology is an arena which explores the synthesis, characterization and application of an array of delivery systems at a one billionth of meter scale. Such systems are implemented to deliver drugs, proteins, vaccines, and peptides. The role of nanotechnology in delivering AMPs is still at its early development stage. There are challenges of incorporating AMPs into drug delivery system. This review intends to explore in depth, the role of nanotechnology in delivering AMPs as well as presenting the current advances and accompanying challenges of the technology.

Metaplastic Breast Cancer: Molecular Typing and Identification of Potential Targeted Therapies at a Single Institution.

INTRODUCTION: Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic subtype of breast cancer comprising approximately 0.5% to 5.0% of all invasive breast cancers with a poor prognosis and limited therapeutic options. PATIENTS AND METHODS: We investigated MBC at our institution to evaluate outcomes and investigate the molecular profile of our cohort to determine the presence of mutations for which there are targeted therapies. RESULTS: We found our cohort to consist mainly of the matrix-producing variant (72%) with 48% having the stereotypical estrogen receptor-negative/progesterone receptor-negative/human epidermal growth factor receptor-2-negative phenotype. While the overall survival of our cohort was an average of 1679 days (4.6 years), we had a surprising number of patients with second primaries (40%) and distant metastases (40%), yet few recurrences (12%). Molecular analysis of the tumors indicated that one gene mutation, CSFIR, was significantly associated with outcome (P = .021); however, the cohort was defined by frequent mutations in ERBB4 (36%), PIK3CA (48%), and FLT3 (60%), for which there are now targeted therapies. CONCLUSION: While surgery is the appropriate first step in the management of this aggressive malignancy, the collection of data pertaining to the use of targeted agents, although anecdotal, may provide clues to better treatment for these patients.

Cardiología "basada en la evidencia": aplicaciones prácticas de la epidemiología. I. La valoración de medicamentos o terapias novedosas / Evidence-based cardiology: practical applications from epidemiology. I. The evaluation of a novel drug or therapy

El incremento sustancial de estudios terapéuticos que utilizan el diseño aleatorio controlado, demanda que el cardiólogo se familiarice con los aspectos esenciales en el diseño y conducción de los mismos, con énfasis particular en la interpretación adecuada y la aplicabilidad de sus resultados. En esta revisión basada en casos clínicos, se discuten algunos aspectos importantes en la valoración de terapia novedosa contemporánea como el uso y análisis de objetivos de eficacia compuestos; implicaciones de la terminación temprana de estudios y la extrapolación de resultados a la población.

The substantial increase of randomized controlled trials demand familiarity with the essential aspects of their design and performance by the cardiologist, particularly the adequate interpretation and applicability of the results. In this clinically-based review, we discuss some important aspects in the assessment of novel contemporary therapy such as the use and analysis of composite endpoints; implications from early termination of trials and extrapolation of results to the population.