1. The effects of antimicrobial peptides WAM-1 and LL-37 on multidrug-resistant Acinetobacter baumannii
John J Spencer, Rowan E Pitts, Rachel A Pearson, Lauren B King Pathog Dis. 2018 Mar 1;76(2). doi: 10.1093/femspd/fty007.
Increasing multidrug resistance (MDR) in Acinetobacter baumannii warrants therapeutic alternatives, and the bactericidal nature of antimicrobial peptides (AMPs) offers a possible approach. In this study, we examined the interaction of cathelicidin AMPs WAM-1, a marsupial AMP, and LL-37, a human AMP, with A. baumannii clinical isolates. We characterized the antibiotic resistance of the isolates, the bacteriostatic and bactericidal effects of these AMPs, synergistic activity with antibiotics, and their effects on biofilm formation and dispersal. All clinical isolates were resistant to commonly prescribed antibiotics, with four of seven isolates showing MDR. WAM-1 and LL-37 showed variable activity in clinical isolates, with WAM-1 having a stronger bacteriostatic effect than LL-37 and showing rapid bactericidal activity against clinical isolates. Furthermore, synergistic bactericidal activity was observed with WAM-1 and commonly prescribed antibiotics. Both peptides were able to inhibit biofilm formation in all clinical isolates at some concentrations, and WAM-1 dispersed mature biofilm in most isolates. LL-37 was unable to disperse mature biofilms in any strains. Further studies must be done to elucidate the true value of these alternative treatments, but these results suggest that MDR A. baumannii's susceptibility to AMPs may result in innovative therapeutics to prevent or treat these infections.
2. Care and support needs of children and young people with cancer and their parents
Wendy Mitchell, Susan Clarke, Patricia Sloper Psychooncology. 2006 Sep;15(9):805-16. doi: 10.1002/pon.1014.
The importance of psychosocial support services for children with cancer and their families is recognised but evaluation of such services is less well developed with little information available about different patterns of provision. This paper provides an overview of psychosocial support children and their families in the UK receive during and after treatment. It reports the results of a postal survey of 303 families, within which parents and children identified their satisfaction with support services and also areas of unmet need. Satisfaction was identified in a range of areas, including medical information and support from nurses and social workers. However, areas of unmet need were also highlighted, especially age appropriate facilities, emotional support and information in different formats. Although British government policy currently seeks to develop standards and guidelines of care throughout the National Health Service, this paper demonstrates that there is still a need to develop psychosocial support services and work towards recently established guidelines in order to ensure that families receive flexible but equitable packages of care and support, wherever treatment is received.
3. Antimicrobial peptide WAM-1: a promising antibacterial and anti-inflammatory drug against carbapenem-resistant Klebsiella pneumoniae
Xiaodong Zhang, Shiyi Shi, Zhuocheng Yao, Xiangkuo Zheng, Wangyang Li, Ying Zhang, Lingbo Wang, Jianming Cao, Tieli Zhou J Antimicrob Chemother. 2022 Jun 29;77(7):1903-1911. doi: 10.1093/jac/dkac128.
Background: The emergence and spread of carbapenem-resistant Klebsiella pneumoniae (CRKP) pose a threat to public health. Antimicrobial peptides provide a new treatment option for CRKP infections. Objectives: We studied antibacterial activities of WAM-1 against CRKP in vitro and in vivo and explored its possible mechanism. We verified safety and factors affecting antibacterial effect. Furthermore, anti-inflammatory effects were investigated. Methods: We selected eight CRKP and eight carbapenem-susceptible K. pneumoniae to explore the antibacterial activity of WAM-1 by broth microdilution (BMD). The possible mechanism was investigated by alkaline phosphatase leakage and propidium iodide (PI). We evaluated safety of WAM-1 by cytotoxicity and haemolysis and effects of temperature and serum on the antibacterial activity. We investigated in vivo efficacy of WAM-1 by the Galleria mellonella infection model. We investigated the effect of WAM-1 on TNF-α. Results: BMD showed that WAM-1 had a good antibacterial effect with MICs of 2-4 mg/L and MBCs of 4-8 mg/L. RT-qPCR showed that WAM-1 could inhibit the expression of TNF-α. The cytotoxicity and haemolysis test proved that WAM-1 had certain potential application in vivo. Alkaline phosphatase leakage and PI fluorescence showed that WAM-1 was highly likely to exert an antibacterial effect by destroying bacterial membrane. The G. mellonella infection model suggested that WAM-1 may have a good therapeutic effect in vivo. Temperature had little effect on the activity of WAM-1. Serum, however, reduced WAM-1 activity. Conclusions: WAM-1 has good antibacterial effect and potential anti-inflammatory effect on infection caused by CRKP.
