Intradermal testing for autoimmune progesterone dermatitis: should we be basing the diagnosis on it?

Autoimmune progesterone dermatitis (APD) is a rare skin disorder with varying presentations, resulting from hypersensitivity to endogenous progesterone during the luteal phase of the menstrual cycle. The diagnosis has been traditionally confirmed with intradermal progesterone testing (IPT) or intramuscular challenge with progesterone or its derivatives. We present a case of a 31-year-old woman with suspected APD who underwent IPT to progesterone. The patient's cyclical symptoms, positive skin reaction and symptoms following IPT were sufficient to make a diagnosis of APD. However, we also tested 10 healthy female controls without symptoms of APD, and found that 9 of these also developed positive skin reactions to intradermal progesterone at 15 min, 24 and 48 h, albeit to a lesser extent. Therefore, these results raise doubts about the validity of using IPT to make a diagnosis of APD. Further research on appropriate testing is needed.

Migrant status and identification as ultra-high risk for psychosis and transitioning to a psychotic disorder.

BACKGROUND: Certain migrant groups are more likely to develop a psychotic disorder compared to the native-born populations, and a younger age at migration is associated with greater risk. However, it is not known at which stage migration has an effect on the development of psychotic disorders. We examined whether migrants were more likely to be identified as ultra-high risk for psychosis (UHR) compared to native-born young people and whether migrant status was associated with the risk of transition to a full-threshold psychotic disorder. METHODS: The cohort included all young people aged 15-24 who were identified as UHR at a specialist clinic over a five-year period (2012-16). Australian census data were used to obtain the at-risk population. Poisson regression was used to calculate rate ratios and Cox regression analysis determined hazard ratios. RESULTS: 467 young people were identified as UHR, of which 13.5% (n = 63) were born overseas. First-generation migrants were 2.6-fold less likely to be identified as UHR compared to Australian-born young people (IRR = 0.39, 95% CI [0.30, 0.51], P < 0.001). There was no difference between migrant and native-born young people in their risk of transitioning to a psychotic disorder (HR = 0.90, 95% CI [0.39, 2.08], P = 0.81). CONCLUSIONS: UHR first-generation migrants may be under-accessing mental health services.

Kaolin exogenous application boosts antioxidant capacity and phenolic content in berries and leaves of grapevine under summer stress.

Heat waves, high light intensities and water deficit are becoming important threats in many important viticultural areas worldwide, so the implementation of efficient and cost-effective mitigation strategies is crucial for the production of premium wines while maintaining productivity. In this context, the foliar application of kaolin, a chemically inert mineral with excellent reflective properties, is being developed and experimented as a strategy to reduce the impact of heat and drought in Douro vineyards (Northern Portugal), already revealing promising results. In the present study we investigated if an improved antioxidant capacity is part of the beneficial effects of kaolin, by studying changes in the enzymatic and nonenzymatic antioxidant system in leaves and berries (cv Touriga Nacional). Results showed that mature grape berries contained higher amounts of total phenols (40%), flavonoids (24%), anthocyanins (32%) and vitamin C (12%) than fruits from control vines, and important changes were also measured in leaves. In parallel, kaolin application improved the antioxidant capacity in berries, which was correlated with the observed increased content in secondary metabolites. Kaolin application also regulated secondary metabolism at the transcriptional level through the increase in the transcript abundance of genes encoding phenylalanine ammonia lyase and chalcone synthase.

Aquaporins are multifunctional water and solute transporters highly divergent in living organisms.

Aquaporins (AQPs) are ubiquitous membrane proteins whose identification, pioneered by Peter Agre's team in the early nineties, provided a molecular basis for transmembrane water transport, which was previously thought to occur only by free diffusion. AQPs are members of the Major Intrinsic Protein (MIP) family and often referred to as water channels. In mammals and plants they are present in almost all organs and tissues and their function is mostly associated to water molecule movement. However, recent studies have pointed out a wider range of substrates for these proteins as well as complex regulation levels and pathways. Although their relative abundance in plants and mammals makes it difficult to investigate the role of a particular AQP, the use of knock-out and mutagenesis techniques is now bringing important clues regarding the direct implication of specific AQPs in animal pathologies or plant deficiencies. The present paper gives an overview about AQP structure, function and regulation in a broad range of living organisms. Emphasis will be given on plant AQPs where the high number and diversity of these transport proteins, together with some emerging aspects of their functionalities, make them behave more like multifunctional, highly adapted channels rather than simple water pores.

Utilization and transport of acetic acid in Dekkera anomala and their implications on the survival of the yeast in acidic environments.

The yeast Dekkera anomala IGC 5153 exhibited a restricted ability to use weak acids as the only carbon and energy sources. Of the monocarboxylic, dicarboxylic, and tricarboxylic acids tested, only acetic acid was used in such a way. The cells were able to grow at acetic acid concentrations of 0.1 to 3% (vol/vol) over a pH range of 3.5 to 5.5, and the specific growth rates decreased exponentially with the increase of the undissociated acetic acid concentration in the culture medium. Transport assays carried out in cells that exhibited higher specific growth rates showed the presence of an acetate-proton symport associated with a simple diffusion component of the undissociated acetic acid, the weight of the latter increasing with the undissociated acid concentration in the culture media. The acetate carrier was shared by propionic, formic, and sorbic acids and was inducible and repressed by glucose and concentrations of undissociated acetic acid in the culture medium above 0.3% (vol/vol). In undissociated acetic acid repression conditions, the lowest values for the yeast specific growth rates were obtained, and the simple diffusion of the undissociated acid was the only mechanism involved in the acetic acid uptake by the cells. The results will be discussed in terms of the high tolerance of D. anomala to the acidic stress conditions present in wine.

Reconstitution of lactate proton symport activity in plasma membrane vesicles from the yeast Candida utilis.

Lactic acid transport was studied in plasma membrane vesicles from the yeast Candida utilis IGC 3092 which were fused with liposomes containing cytochrome c oxidase. After the addition of an electron donor system, these hybrid membrane vesicles were able to generate a proton-motive force of about--150 mV, inside alkaline and negative. In vesicles prepared from lactic acid-grown cells, the uptake of labelled lactic acid, at pH 6.2, under energized conditions, was expressed by a kinetics consistent with the involvement of a mediated transport system. This carrier exhibited a substrate specificity pattern identical to the one found for the lactate-proton symport in intact cells. The transport of labelled lactic acid was accumulative and strongly sensitive to the effects of the protonophore carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone, consistent with the involvement of the proton-motive force in acid uptake, hence with the presence of a proton symport for lactate. Dissipation of the transmembrane electric potential by valinomycin did not have a significant effect on lactate accumulation, whereas abolishing the transmembrane pH gradient (delta pH) by nigericin prevented the accumulation and led to a rapid efflux of the accumulated acid. The data support that the delta pH is the main component of the proton-motive force involved in the transport of the acid and its accumulation. The lactate-proton symport stoichiometry was 1:1, being independent of the pH. Vesicles prepared from glucose-grown cells did not display the capacity to transport and accumulate lactate. However, activity for the carrier was also reconstituted in vesicles obtained from glucose-grown cells after incubation in buffer containing lactic acid. These results were consistent with those obtained in intact cells, which demonstrated that the lactate-proton symport of the yeast C. utilis is inducible.