Infections caused by multidrug-resistant (MDR) Pseudomonas aeruginosa and Klebsiella pneumoniae are a serious worldwide public health concern due to the ineffectiveness of empirical antibiotic therapy. Therefore, research and the development of new antibiotic alternatives are urgently needed to control these bacteria. The use of cationic antimicrobial peptides (CAMPs) is a promising candidate alternative therapeutic strategy to antibiotics because they exhibit antibacterial activity against both antibiotic susceptible and MDR strains. In this study, we aimed to investigate the in vitro antibacterial effect of a short synthetic CAMP derived from the ΔM2 analog of Cec D-like (CAMP-CecD) against clinical isolates of K pneumoniae (n = 30) and P aeruginosa (n = 30), as well as its hemolytic activity. Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of CAMP-CecD against wild-type and MDR strains were determined by the broth microdilution test. In addition, an in silico molecular dynamic simulation was performed to predict the interaction between CAMP-CecD and membrane models of K pneumoniae and P aeruginosa. The results revealed a bactericidal effect of CAMP-CecD against both wild-type and resistant strains, but MDR P aeruginosa showed higher susceptibility to this peptide with MIC values between 32 and >256 μg/mL. CAMP-CecD showed higher stability in the P aeruginosa membrane model compared with the K pneumoniae model due to the greater number of noncovalent interactions with phospholipid 1-Palmitoyl-2-oleyl-sn-glycero-3-(phospho-rac-(1-glycerol)) (POPG). This may be related to the boosted effectiveness of the peptide against P aeruginosa clinical isolates. Given the antibacterial activity of CAMP-CecD against wild-type and MDR clinical isolates of P aeruginosa and K pneumoniae and its nonhemolytic effects on human erythrocytes, CAMP-CecD may be a promising alternative to conventional antibiotics.

Antimicrobial resistance reduces the efficacy of antibiotics. Infections caused by multidrug-resistant (MDR), Gram-negative bacterial strains, such as Klebsiella pneumoniae (MDRKp) and Pseudomonas aeruginosa (MDRPa), are a serious threat to global health. However, cationic antimicrobial peptides (CAMPs) are promising as an alternative therapeutic strategy against MDR strains. In this study, the inhibitory activity of a cationic peptide, derived from cecropin D-like (ΔM2), against MDRKp and MDRPa clinical isolates, and its interaction with membrane models and bacterial genomic DNA were evaluated. In vitro antibacterial activity was determined using the broth microdilution test, whereas interactions with lipids and DNA were studied by differential scanning calorimetry and electronic absorption, respectively. A strong bactericidal effect of ΔM2 against MDR strains, with minimal inhibitory concentration (MIC) and minimal bactericidal concentrations (MBC) between 4 and 16 μg/mL, was observed. The peptide had a pronounced effect on the thermotropic behavior of the 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)/1,2-dimyristoyl-sn-glycero-3-phosphorylglycerol (DMPG) membrane models that mimic bacterial membranes. Finally, the interaction between the peptide and genomic DNA (gDNA) showed a hyperchromic effect, which indicates that ΔM2 can denature bacterial DNA strands via the grooves.

Objectives: The traditional cardiovascular risk factors associated with coronary artery disease in individuals younger than 55 years old was determined in this study. Methods: A retrospective, paired case–control study comprised of patients younger than 55 years old who were admitted to the hospital due to acute coronary syndrome with coronary artery disease from 2011 to 2016. There were two controls per case, paired by age, gender, admission date, and health insurance. Data from patients were collected, such as sociodemographic information, cardiovascular risk factors, and drug therapy information. A conditional logistic regression model was created to evaluate the association between traditional cardiovascular risk factors and coronary artery disease. Results: There were 171 cases and 342 controls included in the study. The median age was 49 years, with a predominance of male gender (80.12%). Nearly 66% of cases had at least one traditional cardiovascular risk factor. The most common risk factors were obesity (57.31%), arterial hypertension (45.62%), and smoking (28.97%). Independent risk factors of coronary artery disease in patients younger than 55 years were arterial hypertension (odds ratio, 2.52; 95% confidence interval, 1.48–4.20; p = 0.001) and smoking (odds ratio, 7.15; 95% confidence interval, 3.19–15.99; p = 0.00). No significant association between diabetes mellitus and coronary heart disease in the global group (odds ratio, 2.04; 95% confidence innterval, 0.91–4.58; p = 0.083) was found. Conclusion: For patients younger than 55 years, with a theoretically lower risk of coronary artery disease due to their age, having one or several traditional risk factors (smoking, arterial hypertension, dyslipidemia, or diabetes mellitus) confers an increased risk of coronary artery disease regardless of age.

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