An Ex Vivo Study of Congenital Pigmented Nevi in Epidermal Reconstructs

In order to study morphologic and functional characteristics of pigment cells in congenital pigmented nevi, autologous or heterologous reconstructs have been made using normal keratinocytes and nevus cells from the dermal-epidermal junction or from the dermis. All these cells, keratinocytes and nevus cells, were used as cell suspensions immediately after dissociation from the tissues or after subsequent brief cultivation in a serum-free medium. Reconstructed epidermis were cultured for 15 days at the air-liquid interface with or without ultraviolet (UV) B exposure. The reconstructs were examined macroscopically (formation of hyperpigmented macules), histologically (pigment cell nesting) and ultrastructurally (pigment structure and transfer). Typical nesting of nevus cells was observed in the dermal-epidermal junction or in the superficial dermis associated with macroscopically detectable small pigmented macules. UVB exposure induced an upward migration of nevus cells in the suprabasal layers of the epidermis. This tissue model can be considered as an excellent system for the ex vivo reproduction of pigmented nevi and as an assay of the sensitivity of nevus cells towards UVB irradiation.     

Disease resistance in Arabidopsisthaliana increases the competitive ability and the predicted probability of long‐term ecological success under disease pressure

Evidence is mounting that flowering by the mast-fruiting Dipterocarpaceae in Southeast Asia is triggered by ENSO events such that seeds are dispersed at the end of ENSO droughts. These droughts induce substantial defoliation and mortality of canopy trees, producing a favorable environment for seedling recruitment in the forest understory. Therefore, seedling release following droughts may have selected for synchronized, supra-annual fruiting in these rain forests. Currently, mast fruiting in Southeast Asia is generally regarded as an evolutionary response to seed predation by nomadic vertebrates. Separating the two causes for mast fruiting, seedling release and predator satiation, may be difficult if they are coupled in nature by ENSO droughts. Nevertheless, if the cue for masting is environmental, then the post-ENSO seedling environment should be considered a potential cause for masting, and if it operates in conjunction with predator satiation, then it may have provided the initial stimulus for supra-annual synchrony in fruiting.     

Higher number of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> CagA EPIYA C phosphorylation sites increases the risk of gastric cancer,but not duodenal ulcer

Background  

Helicobacter pylori infection is one of the most common infections worldwide and is associated with gastric cancer and peptic ulcer. Bacterial virulence factors such as CagA have been shown to increase the risk of both diseases. Studies have suggested a causal role for CagA EPIYA polymorphisms in gastric carcinogenesis, and it has been shown to be geographically diverse. We studied associations between H. pylori CagA EPIYA patterns and gastric cancer and duodenal ulcer, in an ethnically admixed Western population from Brazil. CagA EPIYA was determined by PCR and confirmed by sequencing. A total of 436 patients were included, being 188 with gastric cancer, 112 with duodenal ulcer and 136 with gastritis.     

Strain- and Species-Level Variation in the Microbiome of Diabetic Wounds Is Associated with Clinical Outcomes and Therapeutic Efficacy

1. Download : Download high-res image (265KB)
2. Download : Download full-size image

     

Acetyldehydrorishitinol,a rishitinol-related potato stress metabolite

A controlled atmosphere of ethylene in oxygen elevates rishitin and phytuberin levels in hypersensitive potato tuber tissue and the levels of hitherto unidentified stress metabolises. One of these was isolated and mass spectral, NMR, IR and UV data suggest the structure, 5,8-dimethyl-2[2 acetoxyisopropyl]-1,4-dihydronaphthalene. This new stress metabolise is related to rishitinol by loss of water and acetylation.     

Effect of Cation Composition on the Mechanical Stability of Perovskite Solar Cells

Photoactive perovskite semiconductors are highly tunable, with numerous inorganic and organic cations readily incorporated to modify optoelectronic properties. However, despite the importance of device reliability and long service lifetimes, the effects of various cations on the mechanical properties of perovskites are largely overlooked. In this study, the cohesion energy of perovskites containing various cation combinations of methylammonium, formamidinium, cesium, butylammonium, and 5‐aminovaleric acid is reported. A trade‐off is observed between the mechanical integrity and the efficiency of perovskite devices. High efficiency devices exhibit decreased cohesion, which is attributed to reduced grain sizes with the inclusion of additional cations and PbI₂ additives. Microindentation hardness testing is performed to estimate the fracture toughness of single‐crystal perovskite, and the results indicated perovskites are inherently fragile, even in the absence of grain boundaries and defects. The devices found to have the highest fracture energies are perovskites infiltrated into a porous TiO₂/ZrO₂/C triple layer, which provide extrinsic reinforcement and shielding for enhanced mechanical and chemical stability.     

Mosquito-only flaviviruses,isolated from <Emphasis Type="Italic">Aedes albopictus</Emphasis> in Slovenia: results of a pilot mosquito monitoring program

Autochthonous transmissions of mosquito-borne diseases were described in close proximity to Slovenia where the knowledge of mosquito species and the viruses they transmit remains very scarce. Therefore we aimed to assess the burden mosquitoes bring to the local community and to test mosquitoes for the presence of the selected zoonotic arboviruses, i. e. Dengue (DENV), West Nile (WNV) and Chikungunya (CHIKV). A pilot mosquito monitoring was conducted in 2012 within two municipalities based on adult mosquito trapping. Altogether 2007 adult mosquitoes were caught. Females of Aedes albopictus and Culex pipiens represented the majority of the total mosquito catch. In sites with more households and nearby greenery, catches of Ae. albopictus were more abundant. Highest numbers of Cx. pipiens females were caught close to a nature reserve, where many bird species stop during their migrations. Trapping results are consistent with both species’ feeding behaviour. Female mosquitoes were grouped into 58 pools according to species, location and date of catch. Real time RT-PCRs for WNV, DENV and CHIKV were performed, but no arboviral genomes were detected in any of the tested mosquito pools. However, amplicons were obtained in three pools when using generic RT-PCR markers for flaviviruses. The viruses detected were propagated and isolated in mosquito cell line C3/36 and identified with sequencing as mosquito-only flaviviruses (MOFs). The important contributions of this study are a successful first isolation of MOFs and confirmation of the presence of the invasive mosquito Ae. albopictus in Slovenia.