Epidermal Cell Types Research Articles

Micromorphological leaf epidermal traits as potential taxonomic markers for infrageneric classification of Oxytropis (Fabaceae).

The characteristics of the leaf epidermis have proven to be useful criteria to support taxonomic studies within Fabaceae. However, there are few systematic studies on the taxonomic significance of leaf epidermis of Oxytropis DC. Here, we used light and scanning electron microscopy to investigate leaf epidermal characteristics of 18 species of genus Oxytropis from the Northeastern Margin of Qinghai-Tibet Plateau. Our examination showed two main types of leaf epidermal cells: polygonal and irregular, and four different patterns of anticlinal walls: straight-arched, sinuolate, undulate, and sinuate. All species studied possess anomocytic stomata. Two trichome shapes were identified: strip-like trichomes, that were present only in O.ciliata, and cylindrical trichomes, present in all other species. Epidermal cell shape and anticlinal wall pattern were constant within species and are useful for species delimitation within genus Oxytropis, when combined with other macroscopic traits. The shape of trichomes can be useful for distinguishing O.ciliata from the other investigated species. Stomatal type was the same within the genus and may be used to elaborate the phylogenetic relationships between genera in combination with data on stomata from other genera. Cluster analysis results were largely consistent with the classification of species and sections based on macro morphological data, indicating that foliar epidermis characteristics of Oxytropis can be used as markers for taxonomic identification at the infrageneric classification level. Lastly, our results support the delineation of the section Leucopodia as an independent section but do not support the merging of section Gobicola into section Baicalia.

Gibbin mesodermal regulation patterns epithelial development.

Proper ectodermal patterning during human development requires previously identified transcription factors such as GATA3 and p63, as well as positional signalling from regional mesoderm1-6. However, the mechanism by which ectoderm and mesoderm factors act to stably pattern gene expression and lineage commitment remains unclear. Here we identify the protein Gibbin,encoded by the Xia-Gibbs AT-hook DNA-binding-motif-containing 1 (AHDC1) disease gene7-9, as a key regulator of early epithelial morphogenesis. We find that enhancer- or promoter-bound Gibbin interacts with dozens of sequence-specific zinc-finger transcription factors and methyl-CpG-binding proteins to regulate the expression of mesoderm genes. The loss of Gibbin causes an increase in DNA methylation at GATA3-dependent mesodermal genes, resulting in a loss of signalling between developing dermal and epidermal cell types. Notably, Gibbin-mutant human embryonic stem-cell-derived skin organoids lack dermal maturation, resulting in p63-expressing basal cells that possess defective keratinocyte stratification. In vivo chimeric CRISPR mouse mutants reveal a spectrum of Gibbin-dependent developmental patterning defects affecting craniofacial structure, abdominal wall closure and epidermal stratification that mirror patient phenotypes. Our results indicate that the patterning phenotypes seen in Xia-Gibbs and related syndromes derive from abnormal mesoderm maturation as a result of gene-specific DNA methylation decisions.

Molecular, micromorphological and anatomical study of rangeland species of Atriplex (Chenopodiaceae) in Iran

Atriplex, as the largest genus of the Chenopodiaceae, is well known for its taxonomic complexity resulting from overlapping morphological characters. This halophytic perennial is distributed in salty and dry soils of Eurasia, America and Australia. Atriplex is one of the most widely cultivated rangeland species in Iran, which improves and revitalizes the rangelands. These unique characteristics of Atriplex make it a valuable plant. The present study is the first micromorphological investigation of this genus in Iran. In this study, the molecular evidence, micromorphological and anatomical structure of four species of Atriplex have been considered to evaluate their relationships. The basic shape of the pollen grains in most taxa is subprolate, however prolate and spheroidal pollen grains were recorded for A. lentiformis and A. canescens. One type of trichome (glandular) is described. Here, among the glandular trichomes, density and size of trichomes are considered as valuable characteristics. Micromorphology of epidermis illustrated three types of epidermal cells including puzzle-shaped, polygonal and irregular. Stem cross sections showed rounded shape, but the margins are diff erent between four species. Using nuclear and plastid markers (nrDNA ITS and rpl32-trnL(UAG)), we reconstructed phylogenetic relationships within four species of Atriplex. This data set was analyzed by phylogenetic methods including Bayesian inference, maximum likelihood and maximum parsimony. In phylogenetic analyses, all members of four species formed a well-supported clade (PP = 1; ML/BS = 100/100), divided into three major subclades (I, II and III). The results of the present study showed the usefulness of micromorphological, anatomical and molecular characteristics in taxon delimitation at specific levels.

Molecular, micromorphological and anatomical study of rangeland species of Atriplex (Chenopodiaceae) in Iran

Atriplex, as the largest genus of the Chenopodiaceae, is well known for its taxonomic complexity resulting from overlapping morphological characters. This halophytic perennial is distributed in salty and dry soils of Eurasia, America and Australia. Atriplex is one of the most widely cultivated rangeland species in Iran, which improves and revitalizes the rangelands. These unique characteristics of Atriplex make it a valuable plant. The present study is the first micromorphological investigation of this genus in Iran. In this study, the molecular evidence, micromorphological and anatomical structure of four species of Atriplex have been considered to evaluate their relationships. The basic shape of the pollen grains in most taxa is subprolate, however prolate and spheroidal pollen grains were recorded for A. lentiformis and A. canescens. One type of trichome (glandular) is described. Here, among the glandular trichomes, density and size of trichomes are considered as valuable characteristics. Micromorphology of epidermis illustrated three types of epidermal cells including puzzle-shaped, polygonal and irregular. Stem cross sections showed rounded shape, but the margins are diff erent between four species. Using nuclear and plastid markers (nrDNA ITS and rpl32-trnL(UAG)), we reconstructed phylogenetic relationships within four species of Atriplex. This data set was analyzed by phylogenetic methods including Bayesian inference, maximum likelihood and maximum parsimony. In phylogenetic analyses, all members of four species formed a well-supported clade (PP = 1; ML/BS = 100/100), divided into three major subclades (I, II and III). The results of the present study showed the usefulness of micromorphological, anatomical and molecular characteristics in taxon delimitation at specific levels.

Using quantitative methods to understand leaf epidermal development.

As the interface between plants and the environment, the leaf epidermis provides the first layer of protection against drought, ultraviolet light, and pathogen attack. This cell layer comprises highly coordinated and specialised cells such as stomata, pavement cells and trichomes. While much has been learned from the genetic dissection of stomatal, trichome and pavement cell formation, emerging methods in quantitative measurements that monitor cellular or tissue dynamics will allow us to further investigate cell state transitions and fate determination in leaf epidermal development. In this review, we introduce the formation of epidermal cell types in Arabidopsis and provide examples of quantitative tools to describe phenotypes in leaf research. We further focus on cellular factors involved in triggering cell fates and their quantitative measurements in mechanistic studies and biological patterning. A comprehensive understanding of how a functional leaf epidermis develops will advance the breeding of crops with improved stress tolerance.

Palyno-anatomical characters and their systematic significance in the family Apiaceae from Chitral, eastern Hindu Kush, Pakistan.

The present study was performed to provide a detailed explanation of leaf epidermal anatomy and pollen micromorphological features of selected species of family Apiaceae from Chitral, eastern Hindu Kush region as the basis of forthcoming studies. In the present article pollen morphology of eight species and foliar epidermal of seven species of family Apiaceae have been examined through microscopic techniques. In results two types of pollen prolate (five species) and perprolate (three species) with three colpi have been recorded. The exine ornamentation was found to be regulate, striate, and cerebroid. Largest pollen was found in Heracleum leucocarpum with the polar diameter of 43.25 μm and equatorial diameter of 21.6μm. Smallest pollen was observed in Elaeosticta chitralica with the polar diameter of 18.4μm. The P/E ratio varied from 1.59 to 2.16. Regarding to foliar epidermal anatomy, three types of epidermal cells including rectangular, irregular, and polygonal with variation in anticlinal wall pattern were determined. In the selected species three kinds of stomata comprising anisocytic, anomocytic, and paracytic type were reported in the current research. The size of epidermal cells ranged from 106 × 42.50 μm in Bupleurum falcatum subsp. cernuum and 77.25 × 26.35 μm in Prangos pabularia in adaxial surface. Largest stomatal complex was found in Prangos pabularia both in adaxial 33.55 × 20.05 μm and abaxial 50.25 × 39.40 μm. All the observed quantitative and qualitative features of the species were proved to be useful in the delimitation of species at generic and species level.

Cell biology of the leaf epidermis: Fate specification, morphogenesis, and coordination.

As the outermost layer of plants, the epidermis serves as a critical interface between plants and the environment. During leaf development, the differentiation of specialized epidermal cell types, including stomatal guard cells, pavement cells, and trichomes, occurs simultaneously, each providing unique and pivotal functions for plant growth and survival. Decades of molecular-genetic and physiological studies have unraveled key players and hormone signaling specifying epidermal differentiation. However, most studies focus on only one cell type at a time, and how these distinct cell types coordinate as a unit is far from well-comprehended. Here we provide a review on the current knowledge of regulatory mechanisms underpinning the fate specification, differentiation, morphogenesis, and positioning of these specialized cell types. Emphasis is given to their shared developmental origins, fate flexibility, as well as cell cycle and hormonal controls. Furthermore, we discuss computational modeling approaches to integrate how mechanical properties of individual epidermal cell types and entire tissue/organ properties mutually influence each other. We hope to illuminate the underlying mechanisms coordinating the cell differentiation that ultimately generate a functional leaf epidermis.

The lipid-binding START domain regulates the dimerization of ATML1 via modulating the ZIP motif activity in Arabidopsis thaliana.

In Arabidopsis thaliana, the epidermis is the outermost cell layer composed of many specialized types of epidermal cells, such as pavement cells, trichomes, and guard cells. The homeodomain-leucine zipper (HD-ZIP) class Ⅳ transcription factors (TFs), which are unique to the plant kingdom, have been recognized as key regulators of epidermis development. Unlike animal HD proteins, which can bind to DNA as monomers, plant HD-ZIP class Ⅳ TFs bind to DNA as dimers, although little is known about the regulation of their dimerization process. Here, we show that the homodimerization of ARABIDOPSIS THALIANA MERISTEM LAYER 1 (ATML1) - HD-ZIP class Ⅳ TF that is required for protoderm development - is regulated by the lipid-binding steroidogenic acute regulatory protein-related lipid transfer (START) domain. We found that ATML1 forms homodimer through interaction via its ZIP motif in yeast and plant cells, although the interaction is abolished by generating a mutation into the lipid-binding START domain to disrupt the lipid-binding ability. These results suggest that lipidic ligands function as key regulators of protoderm development via modulating the dimerization of ATML1.

Gene expression profiling of epidermal cell types in C. elegans using Targeted DamID.

The epidermis of Caenorhabditis elegans is an essential tissue for survival as it contributes to the formation of the cuticle barrier, as well as facilitates developmental progression and animal growth. Most of the epidermis consists of the hyp7 hypodermal syncytium, the nuclei of which are largely generated by the seam cells that exhibit stem cell-like behaviour during development. How the seam cell progenitors differ transcriptionally from the differentiated hypodermis is poorly understood. Here, we introduce Targeted DamID (TaDa) in C. elegans as a method for identifying genes expressed within a tissue of interest without cell isolation. We show that TaDa signal enrichment profiles can be used to identify genes transcribed in the epidermis and use this method to resolve differences in gene expression between the seam cells and the hypodermis. We finally predict and functionally validate new transcription and chromatin factors acting in seam cell development. These findings provide insights into cell-type-specific gene expression profiles likely associated with epidermal cell fate patterning.

Species-specific and altitude-related variations in stomatal features of Berberis lycium Royle and B. parkeriana C.K. Schneid

ABSTRACT Epidermal micro-morphological investigations have drawn the consideration of many researchers because of their taxonomic usefulness, but their relationship with environment is not completely known. Keeping this in view, quantitative leaf epidermal features (number of epidermal cells and stomata, and stomata length and width) were examined in the species Berberis lycium Royle and B. parkeriana C.K. Schneid along an altitudinal gradient at three different altitudes in Manoor Valley (Himalaya), Pakistan. A significant variability was found in the size and type of epidermal cells and stomata on both sides of the understory plants leaves. Berberis parkeriana had two types of stomata (anomocytic, and anisocytic) while Berberis lycium possesses a single type of stomata (paracytic). Furthermore, both species had stomata on the abaxial surface only. Berberis parkeriana had higher values of all parameters analyzed; the number of epidermal cells and stomata increased with increasing altitude while the length and width of stomata decreased with increasing altitude. This approach proved extremely valuable for the assessment of environmental impacts on the adaptive potential of plants and subsequent eco-physiological changes.

Development and structure of four different stamens in Clematis macropetala (Ranunculaceae): particular emphasis on staminodes and staminal nectary.

The stamens of angiosperms are diverse in number, colour and structure. The morphological and structural changes of stamens show important evolutionary significance for improving pollination efficiency. In Clematis macropetala, the androecium consists of fertile stamens and tepaloid staminodes. However, studies on the developmental features, structures and possible functions of stamens are few. In this study, the stamen ontogeny, micromorphology and nectary structure of C. macropetala were studied by scanning electron microscopy, light microscopy and transmission electron microscopy. The results indicate that the stamens can be divided into four forms according to shape and anther size: tepaloid staminode (St1), spatulate staminode (St2), linear-spatulate fertile stamen (St3) and linear fertile stamen (St4). The characteristics of stamen development are similar in the early stage but gradually differentiate in the later stage. St1 has delayed development and no anther differentiation. St2 develops abnormally at the early stage of anther differentiation. St3 and St4 are fertile, but their anther sizes are different. Nine epidermal cell types were observed in stamens, with only 4 types in St1 and 6-7 types in St2, St3 and St4. Nectary tissue appears on the adaxial side of the filament base. The nectary is composed of only one layer of secretory epidermal cells, which have a large nucleus, dense cytoplasm and well-developed wall ingrowth. Nectar is released through micro-channels in the cuticle of the outer wall. In Ranunculaceae, the staminal nectary is often located on fertile or sterile stamens, and the position, structure and micromorphology of secretory tissues of the stamen within Ranunculales are discussed.

Arabidopsis EGY1 Is Critical for Chloroplast Development in Leaf Epidermal Guard Cells.

In Arabidopsis thaliana, the Ethylene-dependent Gravitropism-deficient and Yellow-green 1 (EGY1) gene encodes a thylakoid membrane-localized protease involved in chloroplast development in leaf mesophyll cells. Recently, EGY1 was also found to be crucial for the maintenance of grana in mesophyll chloroplasts. To further explore the function of EGY1 in leaf tissues, we examined the phenotype of chloroplasts in the leaf epidermal guard cells and pavement cells of two 40Ar17+ irradiation-derived mutants, Ar50-33-pg1 and egy1-4. Fluorescence microscopy revealed that fully expanded leaves of both egy1 mutants showed severe chlorophyll deficiency in both epidermal cell types. Guard cells in the egy1 mutant exhibited permanent defects in chloroplast formation during leaf expansion. Labeling of plastids with CaMV35S or Protodermal Factor1 (PDF1) promoter-driven stroma-targeted fluorescent proteins revealed that egy1 guard cells contained the normal number of plastids, but with moderately reduced size, compared with wild-type guard cells. Transmission electron microscopy further revealed that the development of thylakoids was impaired in the plastids of egy1 mutant guard mother cells, guard cells, and pavement cells. Collectively, these observations demonstrate that EGY1 is involved in chloroplast formation in the leaf epidermis and is particularly critical for chloroplast differentiation in guard cells.

SARS-CoV-2 infects human adult donor eyes and hESC-derived ocular epithelium.

The SARS-CoV-2 pandemic has caused unparalleled disruption of global behavior and significant loss of life. To minimize SARS-CoV-2 spread, understanding the mechanisms of infection from all possible routes of entry is essential. While aerosol transmission is thought to be the primary route of spread, viral particles have been detected in ocular fluid, suggesting that the eye may be a vulnerable point of viral entry. To this end, we confirmed SARS-CoV-2 entry factor and antigen expression in post-mortem COVID-19 patient ocular surface tissue and observed productive viral replication in cadaver samples and eye organoid cultures, most notably in limbal regions. Transcriptional analysis of ex vivo infected ocular surface cells and hESC-derived eye cultures revealed robust induction of NF-κB in infected cells as well as diminished type I/III interferon signaling. Together these data suggest that the eye can be directly infected by SARS-CoV-2 and implicate limbus as a portal for viral entry.

565 Epidermal remodeling and immunogenicity within sinus tracts in hidradenitis suppurativa at the single-cell resolution

Hidradenitis suppurativa (HS) is a severe chronic inflammatory skin disease affecting human apocrine sweat gland-bearing skin regions. The overall prevalence of HS ranges from 0.05-4.1% with higher occurrence among females and African Americans, and strong associations with smoking and obesity. One unique feature of HS is the development of highly immunogenic keratinized sinus tracts that grow deeply in the dermis which further complicate HS pathogenesis and treatment. Using single cell transcriptomic analyses, we finely dissected different epidermal cell types in the HS lesional skin and revealed significant dysregulation of skin barrier function in the sinus tracts. We demonstrated that sinus tract keratinocytes exhibit dual cell fates of surface epidermis and skin appendages, and derived from progenitors in infundibulum of the apocrine-pilosebaceous unit. By analyzing ligand-receptor expressions between different skin appendages and immune cells, we highlighted Th17 and TNF responses at early and late stages during HS progression, respectively. Our work provides unprecedented understanding of pathological epidermal remodeling in human inflammatory diseases and important implications for therapeutics.

CREB-binding protein (CBP) gene family regulates planarian survival and stem cell differentiation

In developmental biology, the regulation of stem cell plasticity and differentiation remains an open question. CBP(CREB-binding protein)/p300 is a conserved gene family that functions as a transcriptional co-activator and plays important roles in a wide range of cellular processes, including cell death, the DNA damage response, and tumorigenesis. The acetyl transferase activity of CBPs is particularly important, as histone and non-histone acetylation results in changes in chromatin architecture and protein activity that affect gene expression. Many studies have described the conserved functions of CBP/p300 in stem cell proliferation and differentiation. The planarian Schmidtea mediterranea is an excellent model for the in vivo study of the molecular mechanisms underlying stem cell differentiation during regeneration. However, how this process is regulated genetically and epigenetically is not well-understood yet. We identified 5 distinct Smed-cbp genes in S. mediterranea that show different expression patterns. Functional analyses revealed that Smed-cbp-2 appears to be essential for stem cell maintenance. On the other hand, the silencing of Smed-cbp-3 resulted in the growth of blastemas that were apparently normal, but remained largely unpigmented and undifferentiated. Smed-cbp-3 silencing also affected the differentiation of several cell lineages including neural, epidermal, digestive, and excretory cell types. Finally, we analysed the predicted interactomes of CBP-2 and CBP-3 as an initial step to better understand their functions in planarian stem cell biology. Our results indicate that planarian cbp genes play key roles in stem cell maintenance and differentiation.

Morphological and anatomical study of the genus Sambucus L. (Adoxaceae) in Iran

Sambucus (Adoxaceae) is a tall tree-like shrub distributed throughout temperate and subtropical regions in Europe, Asia, North Africa and North America. Since there is not any morphological and anatomical comprehensive study on Sambucus species in Iran and Sambucus nigra is located in the Arasbaran region with very limited distribution, we have encouraged studying the patterns of morphological variation and anatomical structure among Sambucus taxa. In this study, the morphological and anatomical structure of 18 populations from two species of Sambucus (S. ebulus and S. nigra) has been considered to evaluate the relationships in this genus. In total, nine quantitative and nine qualitative morphological features were evaluated and measured. Ward’s dendrogram showed two main clusters. The first cluster is composed of a population of S. nigra. The second cluster was composed of two subsets and contained populations of S. ebulus in Golestan, Mazandaran and Gilan provinces. There were two types of epidermal cells, puzzle-shaped in S. ebulus and oblong cells in S. nigra. The stems are rounded shape in both species. The margin is quite wavy in S. ebulus and straight in S. nigra. Both species showed a rounded shape with a wavy margin in petiole cross-sections. Pedicel cross-sections of both species are similar to each other in the general shape of cross-sections and margins. Both are rounded in shape and the margin is quite sinuous shapes in S. ebulus and wavy in S. nigra. The present study showed that a combination of morphological and anatomical data provides reliable evidence for the differentiation of two species of S. nigra and S. ebulus.

The Immune Function of Keratinocytes in Anti-Pathogen Infection in the Skin

Abstract Keratinocytes, located in the outer part of human skin, are the main epidermal cell type and play an essential role in skins defense against infection. Besides creating a physical barrier between the environment and the internal body, keratinocytes exert powerful immune function in anti-pathogen infection in the skin. At the recognition stage, pattern recognition receptors (PRRs) expressed by keratinocytes sense pathogen-associated molecular patterns (PAMPs) existing in pathogens. Toll like receptors (TLRs) are the most important PRRs in keratinocytes. Other PRRs such as dectin-1 and nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) are also found to participate in this process. Activated PRRs enhance the secretion of cytokines, chemokines and the production of antimicrobial peptides (AMPs). Proinflammatory cytokines tumor necrosis factor-α, interleukin (IL)-1α, IL-6, IL-1β and IL-18, chemokines (C-X-Cmotif) ligand (CXCL) 1, CXCL2, CCL20, CCL2 and IL-8, AMPs human β-defensin (HBD) 2, HBD3 and LL37 are the main molecules expressed in this procedure. Thymic stromal lymphopoietin (TSLP), IL-36γ, IL-17 family member IL-17C and anti-inflammatory cytokine IL-10 can also be secreted. Some molecules produced by keratinocytes such as ribonuclease 5 and 7, S100 proteins own antimicrobial properties. Keratinocytes defense responses can be regulated by internal and external factors. This review summarizes recent advances on the innate immune function of keratinocytes against infection, promoting the finding of a new direction for avoiding severe skin infection as well as the potential treatment of keratinocyte-associated inflammatory dermatosis.

Seed morphology and sculpture of invasive Impatiens capensis Meerb. from different habitats.

Impatiens capensis is an annual plant native to eastern North America that is currently spreading across Europe. In Poland, due to this plant’s rapid spread in the secondary range and high competitiveness in relation to native species, it is considered a locally invasive species. The microstructure of seeds is an important tool for solving various taxonomic problems and also provides data useful for determining the impact of various environmental factors on the phenotypic variability of species. This issue is particularly important in regard to invasive species which occupy a wide range of habitats in the invaded range. There are few reports on seed size and thus far no descriptions of the seed ultrastructure of I. capensis in the analyzed literature. We present new data on the seed morphology of I. capensis growing in different habitats and conditions in the secondary range of the species. The studied populations differed significantly in each of the investigated traits (seed length, width, circumference, area, roundness, and mass). Our findings showed that anthropogenic disturbances in habitats and some soil parameters (presence of carbonates, potassium, loose sand, and moisture) were statistically significant with various seed sizes and morphology in the studied populations of I. capensis. Moreover, our studies showed maximum seed length (5.74 mm) and width (3.21 mm) exceeding those values given in the available literature. For the first time, we also provide a detailed SEM study of the ultrastructure of the seed coat of I. capensis. There are two types of epidermal cells on the seeds: (a) between the ribs (elongated with straight anticlinal walls, slightly concave outer periclinal walls, and micropapillate secondary sculpture on the edges with anticyclic walls), and (b) on the ribs (isodiametric cells with straight anticlinal walls and concave outer periclinal walls). Unlike the variability of size and weight of seeds, the coat ornamentation has turned out to be a steady feature within the studied secondary range of I. capensis.

Taxonomic significance of leaves in family Aizoaceae.

Aizoaceae is one of the most important and widespread succulent plant families in both tropical/subtropical regions and arid zones. In this study, 27 species were collected from various floristic regions in Egypt, Kingdom of Saudi Arabia and cactus farms (Kalupia – Egypt). The morphological characteristics of every taxon were recorded. The important morphological features included: the number of leaves per plant; leaf types; leaf position (cauline or radical; the latter indicates leaves arising from, or near, the roots); leaf arrangement; petiolate or sessile leaves; leaf sheath present or absent; leaf shape; leaf margin; leaf tip; presence of leaf ‘window area’; leaf texture; and presence of white or dark miniscule dots (white miniscule dots from calcium carbonate and dark miniscule dots from tannin sacs). The investigated anatomical features were as follows: shape of the transverse section; the type of epidermal cells; the presence of large epidermal cells (bladder cells); presence of papilla and simple hairs; presence of tannin sacs; shapes of calcium oxalate crystals; shape of the xylem vessels; and the presence of Kranz unit (the unit that constitutes the vascular bundle/s, parenchyma sheath, and surrounding mesophyll) or collenchyma sheath. All data were recorded in a data matrix (as either text or numerical data), which was used to construct the identification key and phylogeny tree using a multi-variate statistical package. The results of our analysis may open the possibility of using the morphological and anatomical features of leaves to distinguish between the subfamilies, genera, and species of Aizoaceae.

Safety and efficacy of a novel home-use device for light-potentiated (LED) skin treatment.

Skin structure and function results from a dynamic interplay between dermal and epidermal cell types. Optimizing skin health through an effective and long-lasting skin care regime therefore requires a global approach, encompassing various mechanisms to stimulate this interplay beyond the action scope of a classical topical solution. This study evaluates the impact of a novel home-use device combining a topical serum, light-emitting diodes and massage on the clinical signs of extrinsic skin aging. The innovative principle relies on potentiating the effect of active ingredients contained in the topical serum with visible and near infra-red photons to prevent extracellular matrix degradation and promote its reconstruction. After in vitro and ex vivo investigations, a clinical study assessed the safety and efficacy of a daily treatment with the home-use device for 28 days. A significant increases in skin density and radiance while reducing the wrinkles was obtained with no side effects.