Subepidermal Layers Research Articles

Free amino acid pool in the rat skin and the skin morphological structure in acute allergic contact dermatitis

The concentration of free amino acids in the skin of rats in experimental acute allergic contact dermatitis (ACD) was studied. Free AAs were determined by reverse-phase high-performance liquid chromatography. Acute ACD was simulated using 2.4-dinitrochlorobenzene. The levels of asparagic and glutamic acids, valine, leucine, phenylalanine, lysine, and taurine increased and methionine, tyrosine, tryptophan, α-aminobutyric acid and anserine decreased in the rat skin during acute ACD development. An imbalance of amino acid metabolism was expressed in an increase in the ratio of aromatic amino acids/branched-chain amino acids by a decrease in the sum of aromatic amino acids. An increase in the Phe/Tyr ratio may indicate a decrease in the activity of the hydroxylase pathway of phenylalanine metabolism in the rat skin. Only in the skin of rats with acute ACD, the levels of valine, isoleucine and lysine were negatively correlated with the level of blood TNF-1α, which confirms their anti-inflammatory effect.Histological examination revealed an inflammatory reaction expressed by lymphocytic infiltration of various skin layers (ectoderm, subepidermal layer). Perivascular proliferation of fibroblasts and formation of subepidermal fibrosis were observed in subepithelial sections. The upper layer of the thorny layer was necrotic, the granular layer with necrosis and pronounced karyopiknosis of nuclei was observed. The epidermis thickness increased, infiltration of lymphocytes and segmented neutrophils into epidermis was noted up to the cells of the thorny layer (exocytosis).The data obtained indicate a significant metabolic imbalance of amino acids in the skin of rats in acute ACD, manifested by depletion of the amino acid pool of aromatic and sulfur-containing amino acids, impaired metabolism of phenylalanine, as well as increased levels of immunogenic amino acids that play a functional role in the regulation of anti-inflammatory, antioxidant system and proliferative activity of immune system cells on the background of a significant inflammatory process.

Hypodermis or multiple epidermis: Leaf ontogenesis in nine species of subfamily Myrtoideae (Myrtaceae)

The ninth largest family of angiosperms is Myrtaceae, which comprises 127 genera and over 6000 species. The leaf anatomy of Myrtaceae has been widely studied and can be used in phylogenetic analyses and species delimitations in complexes within the family. A multiple epidermis and hypodermis have been described for the leaves of representatives of the family but have not been confirmed using ontogenetic studies, which could lead to incorrect interpretations about these tissues. Thus, we studied the leaf ontogenesis of the following 9 species in subfamily Myrtoideae: tribe Syzigieae - Syzigium cumini; tribe Myrteae - Myrceugenia alpigena and M. euosma (subtribe Luminae), Psidium sartorianum, P. guajava, Campomanesia adamantium and Pimenta pseudocaryophyllus (subtribe Pimentinae), Myrcianthes pungens and M. gigantea (subtribe Eugeniinae). Shoot apices and leaves up to the fourth node were transversally and longitudinally sectioned following techniques used for plant anatomy. Leaf development in all species is from apical, intercalary, dorsal, marginal and plate meristematic activity. Protodermal periclinal divisions only occur to give rise to secretory cavities. The results show that in all the species the subepidermal layer is a hypodermis, which originates from periclinal divisions of the ground meristem. The occurrence of this layer could have phylogenetic implications according to reports in the literature, reinforcing the relationships among the subtribes in current topologies of Myrteae. However, the occurrence of a hypodermis in representatives of other subtribes of Myrteae and Syzigieae need to be better studied and discussed in relation to the phylogeny of Myrtaceae.

Frequency and Correlation of Peripheral and Tissue Eosinophilia with Clinical Manifestations in Patients with Bullous Pemphigoid.

Bullous pemphigoid (BP) is an autoimmune disease involving the sub-epidermal layer. Eosinophilia may play a role in the pathogenesis of BP. We aimed to investigate the correlation between dermal or peripheral eosinophilia with clinical presentations in patients with BP. This cross-sectional study was conducted on 108 BP patients from January 2010 to September 2019. Clinical data were recovered. Skin biopsies were re-evaluated, and the Bullous Pemphigoid Disease Area Index (BPDAI) severity score was calculated. Finally, the relationship between clinical features of BP and dermal or peripheral eosinophilia was analyzed. A total number of 108 patients were included in this study. Thirty-five were excluded due to our exclusion criteria. Finally, data from 73 patients were analyzed. Fifty-seven point five percent of the population was female. There was a significant direct correlation (r = 0.33) between BPDAI severity score and tissue eosinophilia (P = 0.03). No significant relationship was found between BPDAI severity score and peripheral eosinophilia (P = 0.52). There were significant positive correlations between tissue eosinophilia with absolute serum eosinophil count (P = 0.002; r = 0.49) and percentage (P < 0.0001; r = 0.89). This study revealed significant relationships between tissue eosinophilia and BP severity. These findings could be useful in clinical practice. The possible role of eosinophils in BP clinical features should be considered as a promising help for better diagnosis and treatment.

Anatomical and histochemical characterization of vegetative organs of Brazilian species of Renealmia (Zingiberaceae)

Abstract Renealmia comprises approximately 85 herbaceous and rhizomatous plants in Africa and America known for their metabolite diversity. This study characterized the anatomy and histochemistry of the vegetative organs of three native Brazilian Renealmia species, R. breviscapa and R. nicolaioides, collected from the Amazon Forest in Acre and R. chrysotricha from the Atlantic Forest in Rio de Janeiro. Samples were fixed and processed using conventional plant anatomy and micromorphology techniques, including histochemical tests to identify classes of compounds in vegetative organs. Characteristics including oil idioblasts, dorsiventral leaf structure, tetracytic stomata, unicellular trichomes, and prismatic crystals were common among the studied species of Renealmia, and thus significant for the family. Distinctive characteristics were identified in the vegetative organs of the three species, including the cellular distribution of root phloem, covering of rhizome tissue, different types and distributions of idioblasts and phenolic trichomes in rhizomes and leaves, presence or absence of petiole, and subepidermal layer in the intercostal region of leaves. Mineral content importance as a diagnostic characteristic of the genus is also emphasized. The results of this study advance the understanding of the distinctive anatomical characteristics of the three species of Renealmia in different environments, two in the Atlantic Forest and one in the Amazon Forest.

Three New Species of the Megadiverse Genus Microlicia (Melastomataceae) with Notes on Leaf Anatomy

Abstract— The new species Microlicia arenaria, M. dentisepala, and M. membranacea are described from the Diamantina Plateau, Minas Gerais state, Brazil. Microlicia arenaria is a cespitose subshrub with xylopodium, fastigiate branches, forming clumps, sessile leaves, linear lamina, and hypanthium and sepals covered with golden spherical glands. In addition, it has dimorphic and bicolored stamens with tetrasporangiate anthers. Microlicia dentisepala has a subshrub or shrub habit, is erect and much branched, and its leaves are small, varnished in appearance, with both surfaces covered with spherical glands. The sepals are triangular to narrowly lanceolate and shorter than the length of the hypanthium, with a tooth aspect. Microlicia membranacea is a subshrub with petiolate leaves, lamina of membranous consistency and suprabasal venation, with prominent secondary veins. The branch, leaf, hypanthium, and sepals are covered with glandular trichomes, and the cylindrical hypanthium is slightly contracted at the apex. Microlicia arenaria and M. dentisepala exhibit some anatomical features common to Microlicia, such as amphistomatic leaves, short-stalked glandular trichomes in depressions on the leaf surface, compact mesophyll, phenolic compounds in the subepidermal layer, idioblasts with druses in the mesophyll, and collateral vascular bundles. Microlicia membranacea stands out by its hypostomatic leaves and a thin mesophyll formed by only three to four cell layers, conditions possibly related to a shaded environment. Following the criteria of the Red List of the International Union for Conservation of Nature (IUCN), we preliminarily assess the conservation status of the species Microlicia arenaria as Endangered (EN), Microlicia dentisepala as Critically Endangered (CR), and Microlicia membranacea as Data Deficient (DD). We provide descriptions of the new species, along with field images, detailed illustrations, and comparisons with related species. Data on geographic distribution and habitat are also presented.

Close orthopedic surgery skin incision with combination of barbed sutures and running subcuticular suturing technique for less dermal tension concentration: a finite element analysis

BackgroundMechanical forces have an important role in the initiation and progression of orthopedic surgical incisions complications. To avoid incision complications with the reduction of dermal tension, surgeons may choose a buried continuous suture technique other than the traditional interrupted vertical mattress suture. Absorbable barbed sutures are widely used in orthopedics due to their convenience and reducing wound tension. The aim of this research is to compare and explain the advantages of running subcuticular suturing technique with absorbable barbed sutures for orthopedic surgical incisions closure.MethodsFinite element models of layered skin and two different suture techniques, running subcuticular suture and intradermal buried vertical mattress suture, ware constructed. The mechanical property difference between standard sutures and barbed sutures was modelled using different contact friction coefficient. Pulling the skin wound was simulated, and the sutures’ pressure on the skin tissue was determined.ResultsCompared with traditional smooth sutures, the barbed sutures effectively increased the contact force for subepidermal layers, which led the less force variation between different layers. The results also suggested that subcuticular suture caused less stress concentration compared with intradermal buried vertical mattress suture.ConclusionsIn conclusion, our study indicated that running subcuticular suturing technique with absorbable barbed sutures for orthopedic surgical incisions closure results in more uniform stress distribution in the dermis. We recommend this combination as the preferred method of skin closure in orthopedic surgery unless contraindicated.

Diversity and evolution of leaflet anatomical characters in the Pterocarpus clade (Fabaceae: Papilionoideae).

The Pterocarpus clade includes 23 genera previously attributed to different Fabaceae tribes. The recent rearrangements of many genera in the clade do not recognize morphological synapomorphies. This study aimed to identify new synapomorphies for the Pterocarpus clade, to identify characters supporting inter-generic relationships currently resolved only by molecular data and to identify diagnostic characters at the genus and species levels. Subterminal leaflets of the studied genera were selected and analyzed using light and scanning electron microscopy. Ancestral reconstruction was performed using morphological and anatomical characters of 16 genera of the Pterocarpus clade. The convex epidermal relief in the region of the main vein indicated the relationship among all genera of the group. Anchor-like multicellular trichomes are features shared by Brya and Cranocarpus, which are the sister group to the other genera of the clade. Subepidermal layers are features shared by the Centrolobium, Etaballia, Paramachaerium, Pterocarpus and Tipuana genera, and the sclerenchyma sheath in the leaflet margin is reported in the Discolobium, Riedeliella and Platymiscium genera. Bulbous based glandular trichomes and vesicular glandular trichomes are diagnostic at the species level in Centrolobium and Pterocarpus, respectively. The leaflet characters investigated can be useful for the taxonomic delimitation at both the genus and species levels of the Pterocarpus clade. Our dataset provides new synapomorphies, elucidates the inter-generic relationships and reinforces the phylogenetic classification of the Pterocarpus clade resolved by molecular data.

Signaling by the EPFL-ERECTA family coordinates female germline specification through the BZR1 family in Arabidopsis.

In most flowering plants, the female germline is initiated in the subepidermal L2 layer of ovule primordia forming a single megaspore mother cell (MMC). How signaling from the L1 (epidermal) layer could contribute to the gene regulatory network (GRN) restricting MMC formation to a single cell is unclear. We show that EPIDERMAL PATTERNING FACTOR-like (EPFL) peptide ligands are expressed in the L1 layer, together with their ERECTA family (ERf) receptor kinases, to control female germline specification in Arabidopsis thaliana. EPFL-ERf dependent signaling restricts multiple subepidermal cells from acquiring MMC-like cell identity by activating the expression of the major brassinosteroid (BR) receptor kinase BRASSINOSTEROID INSENSITIVE 1 and the BR-responsive transcription factor BRASSINOZOLE RESISTANT 1 (BZR1). Additionally, BZR1 coordinates female germline specification by directly activating the expression of a nucleolar GTP-binding protein, NUCLEOSTEMIN-LIKE 1 (NSN1), which is expressed in early-stage ovules excluding the MMC. Mutants defective in this GRN form multiple MMCs resulting in a strong reduction of seed set. In conclusion, we uncovered a ligand/receptor-like kinase-mediated signaling pathway acting upstream and coordinating BR signaling via NSN1 to restrict MMC differentiation to a single subepidermal cell.

A Case of Epidermolysis Bullosa Simplex (Dowling-Meara 1 Type) in Newborn

Epidermolysis bullosa is a rare genetic skin disease in which skin easily peels off and blisters are formed with mild mechanical trauma. It is classified into simple, borderline, dysmorphic, and mixed type. These four subtypes are further classified according to the location of gene mutation and genetic patterns. Epidermolysis bullosa simplex (EBS) is characterized by separation in the epidermal or subepidermal layer. And it is mostly caused by mutation of keratin 5 (KRT5) and KRT14 genes. Recently, genetic test has become increasingly important for diagnosis, confirming subtypes and genetic counseling. And there are moderate correlation exists between the EBS phenotype and genotype. Here, we report a case of 2-day-old boy with EBS Dowling-Meara type (EBS-DM) diagnosed by mutation analysis in KRT14.

Microscopic anatomy of the integument in the ribbon worm Micrura bella (Stimpson, 1857) (Pilidiophora, Nemertea).

The integument of ribbon worms in the order Heteronemertea is distinct from the integuments in the other taxa of nemerteans due to the presence of a special subepidermal glandular layer, the cutis. Among heteronemerteans, the ultrastructure of the cutis has been studied only in the Lineus ruber species complex. In the current study, ultrastructural (transmission electron microscopy) and histochemical studies of the epidermis and the cutis of Micrura bella from the basal Lineage A of the family Lineidae were performed. The epidermis consisted of ciliated and serous gland cells and is separated from the cutis by a layer of the subepidermal extracellular matrix; the basal lamina was not detected. The cutis comprised musculature, two types of mucous and four types of granular gland cells, and pigment cells with four types of granules. In the cutis of juvenile worms, type II granular gland cells and type II mucous cells were not observed. The integument of the caudal cirrus consisted of ciliated and serous gland cells and two intraepidermal lateral nerve cords; the cutis was absent. The compositions of the integument glands of M. bella and the L. ruber species complex are similar, except for the presence of type IV granular gland cells with narrow rod-shaped and lamellated granules exhibiting an alternating dark and light transverse layers and type II mucous cells found only in M. bella.

Integrating the microneedles with carboplatin to facilitate the therapeutic effect of radiotherapy for skin cancers.

In most skin cancer patients, excisional surgery is required to remove tumorous tissue. However, the risk of locoregional recurrence after surgery alone is relatively high, particularly for a locally advanced stage of melanoma. Therefore, additional adjuvant treatments, such as radiotherapy, can be used after surgery to inhibit recurrent melanoma after surgical removal. To enhance local radiotherapy, we present the combined X-ray radiation and radiosensitizers (carboplatin) through microneedles (MNs) to treat melanoma. The MNs could be beneficial to precisely delivering carboplatin into the sub-epidermal layer of the melanoma region and alleviate patients' fear and discomfort during the drug administration compared to the traditional local injection. The carboplatin was loaded into the tips of dissolving gelatin MNs (carboplatin-MNs) through the molding method. The results show gelatin MNs have sufficient mechanical strength and can successfully administer carboplatin into the skin. Both in vitro and in vivo studies suggest that carboplatin can enhance radiotherapy in melanoma treatment. With a combination of radiotherapy and carboplatin, the inhibition effect of carboplatin delivered into the B16F10 murine melanoma model through MNs administration (1.2mg/kg) is equivalent to that through an intravenous route (5mg/kg). The results demonstrate a promise of combined carboplatin and X-ray radiation treatment in treating melanoma by MNs administration.

Microneedle Array-Assisted, Direct Delivery of Genome-Editing Proteins Into Plant Tissue

Genome editing in plants employing recombinant DNA often results in the incorporation of foreign DNA into the host genome. The direct delivery of genome-editing proteins into plant tissues is desired to prevent undesirable genetic alterations. However, in most currently available methods, the point of entry of the genome-editing proteins cannot be controlled and time-consuming processes are required to select the successfully transferred samples. To overcome these limitations, we considered a novel microneedle array (MNA)-based delivery system, in which the needles are horizontally aligned from the substrate surface, giving it a comb-like configuration. We aimed to deliver genome-editing proteins directly into the inner layers of leaf tissues; palisade, the spongy and subepidermal L2 layers of the shoot apical meristem (SAM) which include cells that can differentiate into germlines. The array with needles 2 μm wide and 60 μm long was effective in inserting into Arabidopsis thaliana leaves and Glycine max (L.) Merr. (soybeans) SAM without the needles buckling or breaking. The setup was initially tested for the delivery of Cre recombinase into the leaves of the reporter plant A. thaliana by quantifying the GUS (β-glucuronidase) expression that occurred by the recombination of the loxP sites. We observed GUS expression at every insertion. Additionally, direct delivery of Cas9 ribonucleoprotein (RNP) targeting the PDS11/18 gene in soybean SAM showed an 11 bp deletion in the Cas9 RNP target site. Therefore, this method effectively delivered genome-editing proteins into plant tissues with precise control over the point of entry.

In Search for the Avian Trigeminal Magnetic Sensor: Distribution of Peripheral and Central Terminals of Ophthalmic Sensory Neurons in the Night-Migratory Eurasian Blackcap (Sylvia atricapilla).

In night-migratory songbirds, neurobiological and behavioral evidence suggest the existence of a magnetic sense associated with the ophthalmic branch of the trigeminal nerve (V1), possibly providing magnetic positional information. Curiously, neither the unequivocal existence, structural nature, nor the exact location of any sensory structure has been revealed to date. Here, we used neuronal tract tracing to map both the innervation fields in the upper beak and the detailed trigeminal brainstem terminations of the medial and lateral V1 subbranches in the night-migratory Eurasian Blackcap (Sylvia atricapilla). The medial V1 subbranch takes its course along the ventral part of the upper beak to innervate subepidermal layers and the mucosa of the nasal cavity, whereas the lateral V1 subbranch runs along dorsolateral levels until the nostrils to innervate mainly the skin of the upper beak. In the trigeminal brainstem, medial V1 terminals innervate both the dorsal part and the ventral, magnetically activated part of the principal sensory trigeminal brainstem nuclei (PrV). In contrast, the lateral V1 subbranch innervates only a small part of the ventral PrV. The spinal sensory trigeminal brainstem nuclei (SpV) receive topographically ordered projections. The medial V1 subbranch mainly innervates rostral and medial parts of SpV, whereas the lateral V1 subbranch mainly innervates the lateral and caudal parts of SpV. The present findings could provide valuable information for further analysis of the trigeminal magnetic sense of birds.

Anti-inflammatory Activity of Water Extract of Luvunga sarmentosa (BI.) Kurz Stem in the Animal Models

The study was aimed to determine the anti-inflammatory activity of water extract of the Luvunga sarmentosa stem in an animal model. Twenty-five Wistar rats were divided into five groups (n=5). Group 1 was administered 0.9% normal saline (negative control), group 2 was administered 150 mg/kg diclofenac sodium (positive control), and groups 3 to 5 were administered 50, 300, and 550 mg/kg BW of L. sarmentosa extract, respectively. Carrageenan was injected subcutaneously into each rat's subplantar region of the left hind paw. The paw volume was measured using a plethysmometer. The results showed that the water extract of L. sarmentosa stem (doses of 50, 300, and 550 mg/kg BW) significantly reduced the paw edema volume from the 4th to 5th hour compared to the negative control. The percent inhibition of edema at the 5th hour is 47.45; 46.95; 50.39%. The first phase of the edema (1st and 2nd hour) was not affected by the extract. Meanwhile, diclofenac sodium decreased paw edema volume from the 1st to 5th hour with a percent inhibition of 95.90% at the 5th hour. The histopathology result is relevant to the percentage inhibition of edema. Treatment with L. sarmentosa extract showed slight improvement, destruction of epidermal tissue, hyperkeratotic skin, and subepidermal edema. Meanwhile, positive control showed no inflammatory signs with normal keratin, subepidermal, and subcutaneous layers. The water extract of L. sarmentosa stem has anti-inflammatory activity. This extract effectively reduces the paw edema volume in the late phase with decreased neutrophil infiltration.

Histology and Vascular Architecture Study of Keloid Tissue to Outline the Possible Terminology of Keloid Skin Flaps.

Using the keloid "epidermis" to cover a wound is widely used during treatment for keloids. Many flap terminologies have been used in literature. However, the definition of the flap is not well established. Here, we refined the definition of the flap and associated terminology and explored the survival mechanism of the 'flap' through histological analysis and blood supply studying. Histology and vascular study of keloid was carried out with keloid and its surrounding normal skin tissue which were collected from keloid patients following keloid resection operations. The histological structures and thicknesses of epidermal and subepidermal of the keloids were analyzed and measured using hematoxylin & eosin (H&E) staining. Vascular density and blood perfusion in the subepidermal layer of keloids (KDS) were analyzed using CD31 immunohistochemical staining and a laser speckle contrast imaging system (LSCI), respectively. The vascular network in KDS was visualized by CD31 immunofluorescence staining and three-dimensional reconstruction. 29 pieces of keloid and its surrounding normal skin tissue sample from ten patients were collected. Keloid samples were about 2 cm wide and 5 cm long. The normal skin samples were about 2 to 3 mm in width. The thickness of epidermal layer of keloids was (136.4 ± 35.3) μm, and the thickness of epidermal layer of surrounding normal skin was (78.8 ± 13.9) μm. There was statistical thickness difference between the two layers, t(20) = 7.469, P < 0.001. The total thickness of keloid epidermal and subepidermal layers was 391.4 ± 2.3 μm. The vascular density (13.9 ± 3.4/field) and blood flow perfusion (132.7 ± 31.3) PU in KDS were greater than that of surrounding normal skin (7.8 ± 2.3/field, 73.9 ± 17.9 PU), P < 0.001. Horizontally distributed vessels with several vertical branches were observed in 3D vascular network reconstruction. The epidermal layer of keloid is thicker than that of surrounding normal skin. There is a vascular network structure under it. The vessels mainly locate at a depth of about 150 to 400 μm from the surface of keloid epidermis, randomly distribute and run parallel to the epidermis. Based on these characteristics which may ensure an adequate blood supply, we propose the concept of a "keloid subepidermal vascular network flap." This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Morphological, physiochemical, and transcriptome analysis and CaEXP4 identification during pepper (Capsicum annuum L.) fruit cracking

In pepper (Capsicum annuum L.), fruit cracking is a common physical deformation that not only affects the fruit quality, but also increases the water loss rate during storage and reduces shelf-life and economic value. To comprehensively unravel the putative genes and mechanism underlying fruit cracking, the cracking-susceptible cultivar ‘L92’ was subjected to morphological, physiochemical and transcriptome analyses and an assay of postharvest water loss. The polygalacturonase, peroxidase, and cellulase activity levels and water-soluble pectin and lignin contents were significantly higher in FSC (fruit seriously cracking) fruits than in FNC (fruit without cracking) fruits. The hemicellulose and cellulose contents of FSC fruits were lower than those of FNC fruits; with non-significant differences in chelator trans-1,2-diaminocyclohexane-N,N,N0,N0-tetraacetic acid-soluble pectin and sodium carbonate-soluble pectin levels. By comparing the FSC with the FNC fruits and analyzing differentially expressed gene (DEG) profiles during the fruit cracking process, 1,574 DEGs were identified. Among them, 45 unigenes were significantly enriched in KEGG pathways related to cell wall metabolism and lignin biosynthesis. The silencing of CaEXP4 induced cells in the epidermal layer to be smaller and more neatly and tightly arranged, with a greater number of cell layers of the sub-epidermal layer compared with control fruit. Small structural modifications may lead to changes in cell wall structure and elasticity, which might have caused the fruit cracking. To the best of our knowledge, this is the first morphological, histological, physiochemical, and transcriptome analysis to show the role of CaEXP4 during cracking of pepper fruit.

Transcriptomic Insights on the Preventive Action of Apple (cv Granny Smith) Skin Wounding on Superficial Scald Development.

Superficial scald is a post-harvest chilling storage injury leading to browning of the surface of the susceptible cv Granny Smith apples. Wounding of skins has been reported to play a preventive role on scald development however its underlying molecular factors are unknown. We have artificially wounded the epidermal and sub-epidermal layers of apple skins consistently obtaining the prevention of superficial scald in the surroundings of the wounds during two independent vintages. Time course RNA-Seq analyses of the transcriptional changes in wounded versus unwounded skins revealed that two transcriptional waves occurred. An early wave included genes up-regulated by wounding already after 6 h, highlighting a specific transcriptional rearrangement of genes connected to the biosynthesis and signalling of JA, ethylene and ABA. A later transcriptional wave, occurring after three months of cold storage, included genes up-regulated exclusively in unwounded skins and was prevented from its occurrence in wounded skins. A significant portion of these genes was related to decay of tissues and to the senescence hormones ABA, JA and ethylene. Such changes suggest a wound-inducible reversed hormonal balance during post-harvest storage which may explain the local inhibition of scald in wounded tissues, an aspect that will need further studies for its mechanistic explanation.

Anatomy and Ultrastructure of Galls Induced by Neuroterus quercusbaccarum (Hymenoptera: Cynipidae) on Oak Leaves (Quercus robur).

Simple SummaryGalls induced by insects are commonly found on oak leaves in temperate climates. Their induction and development are, however, still only partially known. Our aim was to present a detailed description of their anatomy and fine structure. Using scanning electron microscopy (SEM), we observed the wax cover of a gall and two types of openings on its surface: one similar to degenerated stomata and the other one that we called “large openings on epidermal protuberance”. Nutritive tissue underwent marked changes with time: in a young gall, the cellular walls were not visible, and a distinct cellular structure appeared only later. In the mound of the gall, there was a distinct subepidermal layer of cells containing dense cytoplasm. Tannins occurred in vacuoles or in cell walls in granular form or in compact formations. The leaf subtending the gall showed additional cell divisions and strong lignification of cell walls in the tissue surrounding the peduncle of the gall.The structure and ultrastructure of two developmental stages of the spangle gall induced by Neuroterus quercusbaccarum (Hymenoptera, Cynipidae) were investigated using light microscopy (LM), fluorescence microscopy (FM), and transmission (TEM) and scanning (SEM) electron microscopy. The general design of the gall structure was typical of Cynipidae, but some structural features distinguished the spangle gall. Previously undescribed, characteristic multicellular epidermal protuberances with large openings were observed in autumn on the surface of galls. These may facilitate the gas exchange between the atmosphere and the inside of the gall, thus assisting larval respiration. The larval chamber is surrounded by both a sclerenchymatous capsule and numerous cells containing calcium oxalate crystals that may both serve as protective barriers. In young galls, the nutritive tissue is a wall-less protoplasmic mass, potentially easily accessible to young larvae with delicate mandibles. Cell walls only develop at a later stage. The nutritive tissue was found to be rich in proteins and lipids, but starch grains were not observed. Cellular topology suggests that spangle galls grow by anticlinal division of marginal epidermal cells and periclinal division of subepidermal cells. Cellular proliferation (hyperplasia) also occurs in the leaf tissue near the connection with the gall peduncle, which eventually lignifies.

Effect of high-intensity light on the photosynthetic activity, pigment content and expression of light-dependent genes of photomorphogenetic Solanum lycopersicum hp mutants

The relationship between photosynthesis, pigment accumulation, and the expression of key light-regulated genes in Solanum lycopersicum hp-1, hp-2 and hp-1.2 photomorphogenetic mutants under conditions of high-intensity light (2000 μm (photons) m−2s−1) was studied.The hp-2 mutant (LA3006) and the hp-1 mutants (LA4012 and LA3538) are deficient in DET1 (De-etiolated 1 and DDB1 (DNA DAMAGE-BINDING PROTEIN 1), respectively, which are components of the CDD complex (COP10, DDB1, DET1). HP mutants are superproducers of various pigments and are sensitive to light. We have shown that HIL (high-intensity light) causes a decrease in PSII activity after 24 and 72 h of irradiation, which was partially restored after 72 h in the WT. The photosynthetic rate noticeably decreased only in LA4012 and LA3538 after 24 h of irradiation. After 72 h, the photosynthetic rate decreased in all mutants, with the exception of hp-1.2 LA0279, but the decrease was most noticeable in LA4012, yet significant changes in the respiration rate were absent. The LA0279 mutant was more capable of accumulating anthocyanin in the cells of the subepidermal parenchyma and chlorenchyma, as well as in the cells at the base of large multicellular glandular trichomes and in the mesophyll. Another important difference was the accumulation of increased amounts of antheraxanthin and phenolic compounds in the leaves of LA0279 after 72 h of HIL irradiation. Unlike LA4012, LA3006, LA0279, and LA3538 sowed a significantincrease in the expression levels of CHS, HY5, and FLS genes after 24 h, which may be one of the reasons for the higher adaptive potential of those three mutants. In addition to that in LA3538, strong light-induced stress led to an increased level of flavonol synthase (FLS) expression in the LA3006, LA0279, and LA4012 mutants.We hypothesize that the photosynthetic apparatus (PA) of the LA0279 mutant, which is deficient in the DET1 and DDB1 genes, is most adapted to prolonged HIL. Most likely, the resistance of PA mutants to HIL is due to a variety of factors, which, in addition to the redistribution of carotenoids, may include morphological features associated with the accumulation of anthocyanin in the epidermis, subepidermal layer, mesophyll and trichomes of leaves and with an increase in leaf thickness.

Pathological nerve patterns in human basal cell carcinoma.

The peculiar combined, or binary involvement of epithelium and stroma makes basal cell carcinoma (BCC) a unique tumour. Nerve fibres have been shown to play an active role in different cancers. A prospective observational study was carried out on punch biopsies harvested within BCC surgical excision specimens. A total of 10 samples of histologically diagnosed BCC, derived from 10 different patients (five females, five males), was included in the study. Within the BCCs, seven different histological sub-types were identified: morphea-like, basosquamous, micronodular, mixed nodular-micronodular, adenoid, nodular and superficial multifocal. Nerve fibres were stained for indirect immunofluorescence targeting protein gene product 9.5. Three different morphological patterns of nerve fibre distribution within the BCCs were identified. Pattern 1 displayed a normal skin nerve pattern, in which the fibres were dislodged by the growing tumour masses. Pattern 2 featured a ball of curved, tangled nerve fibres close to the tumour masses, slightly resembling piloneural collar nerve fibres, wrapped around hair follicles in the normal anatomical setting. Pattern 3 showed nerve fibres crowding in the sub-epidermal layer with focal epidermal hyperinnervation. Such a pattern is reminiscent of the typical anatomical neuro-epithelial interaction in mechanosensory organs. Our study may disclose a hidden third player, of nerves. Thus, tissue involvement of BCCs may be better represented by the triad of epithelium, stroma and nerves, each component retaining some features associated with its developmental setting.