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Summary Background Maintenance of water balance in the stratum corneum (SC) is determined by the content of intercellular lipids and natural moisturizing factors (NMFs) in corneocytes. Aim To investigate the association between the NMFs and (pro)filaggrin and the proteases responsible for the processing of (pro)filaggrin to NMFs in the SC of hydrated and dry skin areas of healthy human subjects. Methods The SC hydration state and the transepidermal water loss (TEWL) were measured using a Corneometer and a Tewameter, respectively. Proteases, (pro)filaggrin and NMFs were extracted from SC samples obtained by tape-stripping of the tested skin. Expression levels of (pro)filaggrin were determined by dot blotting and western blotting, and total NMFs by ultra-high performance liquid chromatography. Expression of the proteases caspase-14, calpain-1 and bleomycin hydrolase was measured by western blotting. Results The levels of (pro)filaggrin were not significantly different between hydrated and dry skin, whereas the level of total NMFs was significantly reduced in dry skin. A negative correlation between (pro)filaggrin and NMFs was found in dry skin (Pearson correlation coefficient r = − 0.57, *P

With the recognition of certain limitations of ex situ methods for conservation of plant genetic resources the Convention on Biological Diversity (CBD) at the 'Earth Summit' in 1992 highlighted the importance of traditional knowledge of indigenous and local communities that are relevant for the conservation and sustainable use of biological diversity and gave considerable attention to on-farm and other forms of in situ conservation. Unlike semi-Static nature of ex situ conservation the in situ or on-farm conservation (OFC) is a dynamic evolutionary process. In developing countries like Republic of Korea, where there is a continuum between the use of traditional and modern cultivars, integration of OFC with already existing gene-bank activities in the country will be an effective approach for conservation and sustainable use of the country's crop genetic resources. However, very little efforts have been made so far in developing strategies for OFC, therefore, in this paper we describe the importance of OFC and strategies for its development in Republic of Korea. Surveys over the last 20 years have shown that the landraces of major crops have been almost replaced by newly bred varieties in the country. But some vegetatively propagated or minor crop species are still being maintained in the farmers' fields. We have identified crop landraces, which can be classified into four different categories from the OFC point of view. These are vegetatively propagated landraces, sexually reproduced landraces, landraces with improved varieties and landraces cultivated for the reasons of personal preference. The related issues on OFC including implementation methods from the point of national cooperative system in designated specific condition are also discussed to ensure the genetic diversity in the fast changing agro-ecosystem of the country.

The applicability of cryopreservation protocols to a broad range of genotypes is a key issue for genebanks. We tried to identify the critical factors causing differences in survival of cryopreserved shoot tips using potato varieties coming from cultivated and wild species. The droplet-vitrification method, a combination of droplet-freezing and solution-based vitrification, was selected from several protocols. High survival after freezing was observed after dehydration with PVS2 for 20 min, cooling shoot tips placed in a droplet of PVS2 solution on aluminum foil strips by immersing the foil strips in liquid nitrogen, warming them by plunging the foil strips into a 0.8 M sucrose solution (at 40 degrees C) for 30 s and unloading in 0.8 M sucrose for 30 min. This optimized protocol was successfully applied to 12 accessions with survival ranging between 64.0 and 94.4%.

The role of pregrowth and preculture treatments in terms of both medium composition and exposure duration on survival of embryonic axes of Citrus madurensis after cryopreservation using the vitrification procedure was investigated. The optimal pregrowth treatment for excised embryonic axes was a 3-day treatment with 0.1M sucrose. Preculture was also essential in increasing survival after cryopreservation. Among the various media and treatment durations evaluated, a 24h-preculture of embryonic axes on medium with 0.3M sucrose and 0.5M glycerol was found to be optimal. Using these pregrowth and preculture conditions followed by treatment at 25 degrees C for 20 min each with a loading solution (0.4M sucrose + 2.0M glycerol) and then the PVS2 vitrification solution, direct immersion in liquid nitrogen, rapid rewarming, unloading in a 1.2M sucrose solution for 20 min and transfer of embryonic axes on recovery medium, 82.5% survival and regrowth without intermediary callus formation were obtained with C. madurensis embryonic axes.