Post-traumatic stress but also aggressive attitudes and behaviour can be found in adolescents living in a context of ongoing community and gang violence in the low-income urban areas of Cape Town, South Africa.

We investigated the long-term effects (15–20 months after therapy) of (a) Narrative Exposure Therapy for Forensic Offender Rehabilitation (FORNET) and (b) the cognitive behavioural intervention ‘Thinking for a Change’ (CBT) on post-traumatic stress disorder (PTSD) and aggression compared with a waiting list.

Fifty-four young males participated in the treatment trial, of which 17 completed the FORNET intervention, 11 the CBT intervention, and 26 were on a waiting list. The primary outcome was the change score for the Appetitive Aggression Scale; secondary outcomes were the PTSD Symptom Scale-Interview change scores, and the number of perpetrated violent event types.

The reduction in scores for PTSD that had been observed in FORNET completers at the first follow-up were still significant at the second long-term follow-up (Cohen’s d = 0.86). In this treatment arm (FORNET), the scores for appetitive aggression were also significantly reduced (Cohen’s d = 1.00). There were no significant changes observed for CBT or for the waiting list.

The study indicates that FORNET can successfully reduce post-traumatic stress as well as the attraction to violence even for individuals living under conditions of continuous traumatic stress.

Interactions between human lysozyme (HL) and the lipopolysaccharide (LPS) of Klebsiella pneumoniae O1, a causative agent of lung infection, were identified by surface plasmon resonance. To characterize the molecular mechanism of this interaction, HL binding to synthetic disaccharides and tetrasaccharides representing one and two repeating units, respectively, of the O-chain of this LPS were studied. pH-dependent structural rearrangements of HL after interaction with the disaccharide were observed through nuclear magnetic resonance. The crystal structure of the HL-tetrasaccharide complex revealed carbohydrate chain packing into the A, B, C, and D binding sites of HL, which primarily occurred through residue-specific, direct or water-mediated hydrogen bonds and hydrophobic contacts. Overall, these results support a crucial role of the Glu35/Asp53/Trp63/Asp102 residues in HL binding to the tetrasaccharide. These observations suggest an unknown glycan-guided mechanism that underlies recognition of the bacterial cell wall by lysozyme and may complement the HL immune defense function.