Common skin bacteria protect their host from oxidative stress through secreted antioxidant RoxP.

Cutibacterium acnes is an abundant skin commensal with several proposed mutualistic functions. A protein with strong antioxidant activity was recently identified from the C. acnes secretome. This protein, termed RoxP, facilitated aerobic bacterial growth in vitro and ex vivo. As reducing events naturally occurred outside of the bacterial cell, it was further hypothesized that RoxP could also serve to modulate redox status of human skin. The biological function of RoxP was here assessed in vitro and in vivo, through oxidatively stressed cell cultures and through protein quantification from skin affected by oxidative disease (actinic keratosis and basal cell carcinoma), respectively. 16S rDNA amplicon deep sequencing and single locus sequence typing was used to correlate bacterial prevalence to cutaneous RoxP abundances. We show that RoxP positively influence the viability of monocytes and keratinocytes exposed to oxidative stress, and that a congruent concentration decline of RoxP can be observed in skin affected by oxidative disease. Basal cell carcinoma was moreover associated with microbial dysbiosis, characterized by reduced C. acnes prevalence. C. acnes's secretion of RoxP, an exogenous but naturally occurring antioxidant on human skin, is likely to positively influence the human host. Results furthermore attest to its prospective usability as a biopharmaceutical.

Ara h 1 and Ara h 6 Sensitization Causes Clinical Peanut Allergy in Ara h 2-Negative Individuals.

BACKGROUND: Of the major peanut allergens, sensitivity to Ara h 2 has the highest prediction for clinical allergy. In this study, we evaluated sensitization to peanut components in Iceland and related Ara h 2-negative sensitization to clinical allergy. METHODS: Ara h 1, Ara h 2, Ara h 3, Ara h 8, and Bet v 1 IgEs were measured (ImmunoCAP) in 220 peanut IgE (Pn-IgE)-positive serum samples. Ara h 2 IgE-negative individuals were invited to an open peanut challenge and evaluated for Ara h 6 and 9 sensitization (ISAC microarray). RESULTS: The Ara h 2 IgE-negative group (52.3%, 115/220) was older (p = 0.04) and more likely to have a history of pollen allergy than the Ara h 2-positive group (p < 0.001). Of the Ara h 2-negative participants, 24.3% were already consuming peanuts and 38.3% were unavailable. Of the 43 who underwent an open peanut challenge, 79% were negative, 14% were positive, and 7% were inconclusive. Those who reacted to peanuts had a higher Ara h 1 IgE than that of the tolerant participants, and 3 were positive to Ara h 6 IgE, and 2 of those subjects were monosensitized. Ara h 8 may have caused a positive reaction, while Ara h 9 did not. CONCLUSIONS: Half of the peanut-sensitized individuals in Iceland were not sensitized to the major allergen Ara h 2. Ara h 1, Ara h 3, and Ara h 6 sensitizations resulted in a positive open peanut challenge and they are therefore clinically important for individuals with a peanut allergy in Iceland.

[The incidence and mortality of ARDS in Icelandic intensive care units 1988-1997]. / Brátt andnau[eth]arheilkenni (ards) á gjörgaesludeildum á Islandi 1988-1997.

OBJECTIVE: A retrospective analysis of the epidemiology and intensive care treatment of ARDS in Iceland during the 10 year period, 1988-1997 with observation of trends within the period. MATERIAL AND METHODS: All ICU admissions in Iceland 1988-1997 were reviewed according to the American-European consensus conference criteria on ARDS to select patients with the diagnosis of ARDS i.e. bilateral pulmonary infiltrates, PaO(2)/FiO(2) <200 and excluding patients with signs of heart failure or a pulmonary capillary wedge pressure (PCWP) >18 mmHg. Data were collected on age, gender, length of stay, ventilator treatment and ventilatory modes, causes of ARDS and mortality. RESULTS: A total of 220 patients with severe respiratory failure were found and 155 of them were diagnosed as having ARDS or an annual incidence of 15.5 cases/year or 5.9 cases/100.000/year. If reference population >15 years of age is used for calculation the incidence is 7.8 cases/100.000/year. Hospital mortality was 40%, mean length of ICU stay was 21 days, mean hospital length of stay 39 days. The incidence of ARDS increased during the period with a tendency to lower mortality rates. Mortality was significantly lower when pressure controlled ventilation was used, compared to volume controlled ventilation. CONCLUSION: The incidence of ARDS in a well defined population of Iceland is lower than recent studies in USA and Europe have shown or 5.9 cases/100.00/year but is increasing. The mortality is 40% and shows a slight downward trend, which may be due to the use of lung protective ventilation.