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Pivotal barrier properties of the hydrophobic plant cuticle covering aerial plant surfaces depend on its physicochemical composition. Among plant species and organs, compounds of this boundary layer between the plant interior and the environment vary considerably but cuticle-related studies comparing different organs from the same plant species are still scarce. Thus, this study focused on the cuticle profiles of Physalis peruviana, Physalis ixocarpa, Alkekengi officinarum, and Nicandra physalodes species. Inflated fruiting calyces enveloping fruits make Physalis, Alkekengi, and Nicandra highly recognizable genera among the Solanoideae subfamily. Although the inflation of fruiting calyces is well discussed in the literature still little is known about their post-floral functionalities. Cuticular composition, surface structure, and barrier function were examined and compared in fully expanded amphistomatous leaves, ripe astomatous fruits, and fully inflated hypostomatous fruiting calyces. Species- and organ-specific abundances of non-glandular and glandular trichomes revealed high structural diversity, covering not only abaxial and adaxial leaf surfaces but also fruiting calyx surfaces, whereas fruits were glabrous. Cuticular waxes, which limit non-stomatal transpiration, ranged from <1 μg cm−2 on P. peruviana fruiting calyces and N. physalodes fruits to 22 μg cm−2 on P. peruviana fruits. Very-long-chain aliphatic compounds, notably n-alkanes, iso-, and anteiso-branched alkanes, alkanols, alkanoic acids, and alkyl esters, dominated the cuticular wax coverages (≥86%). Diversity of cuticular wax patterns rose from leaves to fruiting calyces and peaked in fruits. The polymeric cutin matrix providing the structural framework for cuticular waxes was determined to range from 81 μg cm−2 for N. physalodes to 571 μg cm−2 for A. officinarum fruits. Cuticular transpiration barriers were highly efficient, with water permeabilities being ≤5 × 10−5 m s−1. Only the cuticular water permeability of N. physalodes fruits was 10 × 10−5 m s−1 leading to their early desiccation and fruits that easily split, whereas P. peruviana, P. ixocarpa, and A. officinarum bore fleshy fruits for extended periods after maturation. Regarding the functional significance, fruiting calyces establish a physicochemical shield that reduces water loss and enables fruit maturation within a protective microclimate, and promotes different seed dispersal strategies among plant species investigated.

Os pacientes portadores do Diabetes Mellitus (DM), tipo 1 e tipo 2, possuem maiores chances de desenvolver doenças periodontais com maior velocidade de progressão e gravidade. O objetivo do estudo é apresentar a relação bidirecional entre por meio da revisão da literatura, a relação bidirecional entre Doença Periodontal (DP) e Diabetes Mellitus em crianças e adolescentes. Foram pesquisados artigos de estudos observacionais nas bases de dados BVS (Lilacs e Bbo), Pubmed e Scielo, publicados entre 2008 e 2018. Os artigos evidenciaram que a Doença Periodontal tem característica inflamatória multifatorial, que em estágios mais graves pode evoluir para mobilidade e perda precoce dos dentes. Desta forma, a literatura evidencia uma forte ligação bidirecional entre a saúde bucal e a saúde sistêmica, sendo a Diabetes Mellitus um fator de risco para a periodontite em crianças e adolescentes. Esse estudo reitera a relação bilateral entre doença periodontal e Diabetes Mellitus e demonstra que crianças e adolescentes com essa condição sistêmica podem sofrer alterações na resistência bacteriana e exacerbar infecções existentes.

The search for a universal explanation of the altitudinal limit determined by the alpine treeline has given rise to different hypotheses. In this study, we revisited Michaelis’ hypothesis which proposed that an inadequate “ripening” of the cuticle caused a greater transpiration rate during winter in the treeline. However, few studies with different explanations have investigated the role of passive mechanisms of needles for protecting against water loss during winter in conifers at the treeline. To shed light on this, the cuticular transpiration barrier was studied in the transition from subalpine Pinus uncinata forests to alpine tundra at the upper limit of the species in the Pyrenees. This upper limit of P. uncinata was selected here as an example of the ecotones formed by conifers in the temperate mountains of the northern hemisphere. Our study showed that minimum leaf conductance in needles from upper limit specimens was higher than those measured in specimens living in the lower levels of the sub-alpine forest and also displayed lower cuticle thickness values, which should reinforce the seminal hypothesis by Michaelis. Our study showed clear evidence that supports the inadequate development of needle cuticles as one of the factors that lead to increased transpirational water losses during winter and, consequently, a higher risk of suffering frost drought.