Filaggrin mutations in relation to skin barrier and atopic dermatitis in early infancy.

BACKGROUND: Loss-of-function mutations in the skin barrier gene filaggrin (FLG) increase the risk of atopic dermatitis (AD), but their role in skin barrier function, dry skin and eczema in infancy is unclear. OBJECTIVES: To determine the role of FLG mutations in impaired skin barrier function, dry skin, eczema and AD at 3 months of age and throughout infancy. METHODS: FLG mutations were analysed in 1836 infants in the Scandinavian population-based PreventADALL study. Transepidermal water loss (TEWL), dry skin, eczema and AD were assessed at 3, 6 and 12 months of age. RESULTS: FLG mutations were observed in 166 (9%) infants. At 3 months, carrying FLG mutations was not associated with impaired skin barrier function (TEWL > 11·3 g m-2  h-1 ) or dry skin, but was associated with eczema [odds ratio (OR) 2·89, 95% confidence interval (CI) 1·95-4·28; P < 0·001]. At 6 months, mutation carriers had significantly higher TEWL than nonmutation carriers [mean 9·68 (95% CI 8·69-10·68) vs. 8·24 (95% CI 7·97-8·15), P < 0·01], and at 3 and 6 months mutation carriers had an increased risk of dry skin on the trunk (OR 1·87, 95% CI 1·25-2·80; P = 0·002 and OR 2·44, 95% CI 1·51-3·95; P < 0·001) or extensor limb surfaces (OR 1·52, 95% CI 1·04-2·22; P = 0·028 and OR 1·74, 95% CI 1·17-2·57; P = 0·005). FLG mutations were associated with eczema and AD in infancy. CONCLUSIONS: FLG mutations were not associated with impaired skin barrier function or dry skin in general at 3 months of age, but increased the risk for eczema, and for dry skin on the trunk and extensor limb surfaces at 3 and 6 months.

SARS/avian coronaviruses.

In the hunt for the aetiology of the SARS outbreak in 2003, a newly developed virus DNA micro-array was successfully used to hybridise PCR products obtained by random amplification of nucleic acids extracted from a cell culture infected with material from a SARS patient. The SARS agent was found to hybridise with micro-array probes from both coronaviruses and astroviruses, but one of the coronavirus probes and the four astrovirus probes contained redundant sequences, spanning a highly conserved motif, named s2m, found at the 3' end of the genomes of almost all astroviruses, one picornavirus, and the poultry coronaviruses. The three other coronavirus probes, that hybridised with the SARS agent, were located in the replicase gene, and it could be concluded that the SARS agent was a novel coronavirus, harbouring s2m. The presence of this motif in different virus families is probably the result of recombinations between unrelated viruses, but its presence in both poultry and SARS coronaviruses could suggest a bird involvement in the history of the SARS coronavirus. A recent screening of wild birds for the presence of coronaviruses, using a pan-coronavirus RT-PCR, led to the identification of novel coronaviruses in the three species studied. Phylogenetic analyses performed on both replicase gene and nucleocapsid protein could not add support to a close relationship between avian and SARS coronaviruses, but all the novel avian coronaviruses were found to harbour s2m. The motif is inserted at a homologous place in avian and SARS coronavirus genomes, but in a somewhat different context for the SARS coronavirus. If the presence of s2m in these viruses is a result of two separate recombination events, this suggests that its particular position in these genomes is the only one that would not be deleterious for coronaviral replication, or that it is the result of a copy-choice recombination between coronaviruses, following an ancestral introduction in the coronavirus family by an unrelated virus. In conclusion, the relative high frequencies of recombination observed both experimentally and in the natural evolution of RNA viruses, indicate that horizontal gene transfer does occur, even between unrelated viruses. This might represent a challenge in the rapid identification of novel pathogens with DNA micro-array techniques.

Screening of feral pigeon (Colomba livia), mallard (Anas platyrhynchos) and graylag goose (Anser anser) populations for Campylobacter spp., Salmonella spp., avian influenza virus and avian paramyxovirus.

A total of 119 fresh faecal samples were collected from graylag geese migrating northwards in April. Also, cloacal swabs were taken from 100 carcasses of graylag geese shot during the hunting season in August. In addition, samples were taken from 200 feral pigeons and five mallards. The cultivation of bacteria detected Campylobacter jejuni jejuni in six of the pigeons, and in one of the mallards. Salmonella diarizona 14: k: z53 was detected in one graylag goose, while all pigeons and mallards were negative for salmonellae. No avian paramyxovirus was found in any of the samples tested. One mallard, from an Oslo river, was influenza A virus positive, confirmed by RT-PCR and by inoculation of embryonated eggs. The isolate termed A/Duck/Norway/ 1/03 was found to be of H3N8 type based on sequence analyses of the hemagglutinin and neuraminidase segments, and serological tests. This is the first time an avian influenza virus has been isolated in Norway. The study demonstrates that the wild bird species examined may constitute a reservoir for important bird pathogens and zoonotic agents in Norway.