Background. Decedents who remain unidentified and/or unclaimed following postmortem investigations are an international occurrence. Salt River Mortuary (SRM), one of the largest and busiest mortuaries in Cape Town, South Africa, also experiences this burden; however, little is known about the nature of these cases. Objectives. To review all cases admitted to SRM between 1 January 2010 and 31 December 2017 (n=26 960), with the objectives of quantifying the number of decedents who remained unidentified, and to better understand circumstances surrounding death and the identification methods that were attempted. Methods. Data pertaining to unidentified cases were collected from mortuary burial records and medicolegal case files. Data were analysed using Microsoft Excel 2013 (Microsoft, USA). Results. Over the 8-year period, 2 476 cases (mean 9.2% of caseload per annum) admitted to SRM remained unidentified. Bodies underwent an autopsy after a median of 3 days after a death declaration. However, in cases of decomposition, skeletonisation or other physical inhibitors of visual identification (n=345; 14.1%), the time between death and autopsy was undetermined owing to the overall lack of entomology analyses. Approximately 56.9% (n=1 408) of cases were between 20 and 50 years of age, and were predominantly males (78.7%). Unnatural injury-related deaths accounted for 32.4% of unidentified deaths, with firearms, assault and stabbings contributing approximately one-third each. With regard to identification attempts, forensic anthropology was requested in only 1.5% of these cases, and DNA analysis appeared to be used in only 23.6% of cases. Data pertaining to secondary identifiers, forensic odontology and fingerprint analyses were not formally recorded. Conclusions. The relatively short time interval between death declaration and postmortem examination suggests that DNA analysis should be more regularly utilised. Furthermore, it is urged that other ancillary investigations should be more regularly employed; that there is a greater collaboration between stakeholders and identification attempts; and that results are centrally recorded.

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The rapid emergence of antibiotic resistant bacterial pathogens constitutes a critical problem in healthcare and requires the development of novel treatments. Potential strategies include the exploitation of microbial social interactions based on public goods, which are produced at a fitness cost by cooperative microorganisms, but can be exploited by cheaters that do not produce these goods. Cheater invasion has been proposed as a 'Trojan horse' approach to infiltrate pathogen populations with strains deploying built-in weaknesses (e.g. sensitiveness to antibiotics). However, previous attempts have been often unsuccessful because population invasion by cheaters was prevented by various mechanisms including the presence of spatial structure (e.g. growth in biofilms), which limits the diffusion and exploitation of public goods.Here we followed an alternative approach and examined whether the manipulation of public good uptake and not its production could result in potential 'Trojan horses' suitable for population invasion. We focused on the siderophore pyoverdine produced by the human pathogen Pseudomonas aeruginosa MPAO1 and manipulated its uptake by deleting and/or overexpressing the pyoverdine primary (FpvA) and secondary (FpvB) receptors. We found that receptor synthesis feeds back on pyoverdine production and uptake rates, which led to strains with altered pyoverdine-associated costs and benefits. Moreover, we found that the receptor FpvB was advantageous under iron-limited conditions but revealed hidden costs in the presence of an antibiotic stressor (gentamicin). As a consequence, FpvB mutants became the fittest strain under gentamicin exposure, displacing the wildtype in liquid cultures, and in biofilms and during infections of the wax moth larvae Galleria mellonella, which both represent structured environments. Our findings reveal that an evolutionary trade-off associated with the costs and benefits of a versatile pyoverdine uptake strategy can be harnessed for devising a Trojan horse candidate for medical interventions.

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In order to deduce the ancestral genome arrangement in the karyotypically diverse marsupial family Macropodidae, and to assess chromosome change in this family, chromosome-specific paints from the tammar wallaby (2n = 16) were hybridized to metaphase spreads from the two species proposed to represent the 2n = 22 ancestral karyotype, as well as species with derived 2n = 20 and 2n = 14 karyotypes. Identical patterns were observed in the two 2n = 22 species, from which the rearrangements to form the three derived karyotypes may be easily deduced to be 1, 3 and 4 different fusions, respectively. The identical Thylogale and Dorcopsis genomes may both be used to represent the pleisiomorphic macropodid chromosome complement. Variation in the X chromosome was also investigated by hybridizing an X-Y shared tammar wallaby 12-kb repeat element to chromosomes from the other four macropodid species, finding that it hybridized only to the most closely related species, and therefore is of recent origin.