Characteristics of Leaf Epidermis of 22 Lilieae (Liliaceae) under Different Altitudes in China

In this study, 22 leaf samples of 22 Lilieae species were collected in six Province at 90 - 3740 m to study the variations of leaf characteristics with altitude change. The Qualitative character of leaf epidermis and two stomatal indexes, viz. stomatal area (SA), stomatal index (SI), were analyzed in laboratory. The results show that: 1) the shape of the leaf epidermis cells and the pattern of the anticlinal walls provide some useful taxonomic information to distinguish the genus, however, none of the stable traits are exclusive to a genus;2) there are significant or even very significant linear correlations between the two indexes and altitude, of which SA exhibit a negative correlation with altitude (r2 = 0.294, p = 0.009), while SI exhibit a positive correlation with altitude (r2 = -0.254, p = 0.017). As a result, the pattern of leaf cells and anticlinal walls is influenced by genetic factors, while the stomatal area and stomatal index are influenced by environmental factors. Members of the tribe Lilieae have a relatively stable elevation range, which is related to their long-term adaptation to the local environment in the structure of their leaf epidermis.

Ultrastructure of Epidermis and Flesh of the Developing Apple Fruit

The ultrastructure of the epidermis and flesh of apple ( Malus domestica Borkh cv. Red Fuji) fruit was systematically observed during the fruit development via transmission electron microscopy. The results showed that, in spite of the ultrastructural changes in many aspects of the developing fruit epidermal cells, it remained almost unchanged throughout the whole developmental process that the cytoplasm was filled with numerous endoplasmic reticula (ER). Most of these endoplasmic reticula were tube_like and rough_ER with enlarged cisterna from which many vesicles were produced. Some of the vesicles were shown to merge into vacuole. Some dynamic Golgi bodies were also found. All the ultrastructural characteristics showed that the epidermal cells have the features of excretory cells. The ultrastructure of the fruit flesh cells at the young fruit stage were shown to be metabolically active, characterized by the presence of numerous clustered plasmodesmata, cisterna enlarged_ and rough_ER filling the cytoplasm, plenty of vesicles and Golgi bodies, indicating their dynamic cellular transport function. Some giant_circular rough_ERs were found. All the ultrastructural features at this early developmental stage should be closely associated with the enlargement of the young fruit. At the rapid growing phase of the fruit the main changes were characterized by: the starch grain_filled amyloplasts, furcating of the single orifice of plasmodesmata, and the cytoplasm enrichment of both the Golgi body_formed vesicles and other vesicles. These features correspond well with those of a photoassimilate sink_cell. An ultrastructural degeneration phenomenon was observed at the fruit ripening stage, but the mitochondria and plasmalemma still remained intact, which might be related to the continuous development of fruit quality during the fruit ripening.

Correlation of Microstructure of Leaf Sheath Epidermis and Nutrient Composition of Palm Plants with the Damage Degree of Red Palm Fiber Elephant

[ Objective] Correlation of microstructure of leaf sheath epidermis and nutrient composition of palm plants with the damage degree of red palm fiber elephant in four kinds of plants in Nanning were analyzed in order to control the occurrence and damage of this insect in Nanning. [Method] Taken 4 kinds of Palmae plants in Nanning including Ravenea fivulafis, Washingtonia filifera, Phoenix canafiensis, Roystonea regia （HBK.）O. F. Cook as materials, damage situation of the red palm fiber elephant was investigated, microstructure of leaf sheath epidermis and nutrient composition of palm plants were analyzed and determined. [ Result] The results showed that there was direct correlation between the microstructure of leaf sheath epidermis and nutrient composition with the physical resistance of palm plant against red palm fiber elephant. The extend of damage from red palm fiber elephant had negatively relation with the thickness of corneum and leaf epidermis. The damage degree caused by red palm fiber elephant increased with the content of crude protein, crude ash and nitrogen free extract increasing, also increased with the content of rude fiber decreasing. [Condusion] The damage degree of red palm fiber elephant had a relationship with microstructure of leaf sheath epidermis and nutrient composition of palm plants.

Effect of Ambient Humidity on the Transmission of UV/Visible Light through Model Human Epidermis

Transmission of light through model human epidermal samples is investigated at four different wavelengths and at varying ambient humidity. Light from light emitting diodes (LEDs) is used for transmission measurements through the samples at a UVA wavelength of 365 nm, and visible wavelengths of 460 nm, 500 nm, and 595 nm. Ambient air-humidity is varied between 20% and 100%. Results show that for high ambient humidity, near 100%, transmission of light through the epidermis is higher than at low ambient humidity, 60% or lower. These results are explained with a simple model of epidermis as a turbid medium and the effect of adsorbed water in reducing light-scattering by refractive-index-matching. Biological implications of increased light-transmission through epidermis at high ambient humidity are discussed.

Transglutaminase 3 expression in C57BL/6J mouse embryo epidermis and the correlation with its differentiation

Epidermal-type transglutaminase 3 (TGM3) is involved in the cross-linking of structural proteins to form the cornifiedenvelope in the epidermis. In the present study, we detected the expression of TGM3 in the mouse embryo using RT-PCR.TGM3 mRNA is weakly presented from E11.5 to E14.5 and increases significantly from E15.5 to birth. Then wedetermined the spatial and temporal expression pattern of TGM3 in the skin and other organs by in situ hybridization. Wefound a deprivation of TGM3 in skin at E11.5, while a rich supply in periderm cells and a weak expression in basal cellsfrom E12.5 to E14.5. From the period of E15.5 to E16.5, after keratinization in the epidermis, TGM3 was expressed inthe granular and cornified layers. The electron microscopic observation of the C57BL/6J mouse limb bud skin develop-ment provided several morphological evidences for the epidermal differentiation. The above findings suggest that theexpression of TGM3 plays a important role in the epidermis differentiation in embryogenesis.

Morphological characteristics of leaf epidermis and size variation of leaf,flower and fruit in different ploidy levels in Buddleja macrostachya (Buddlejaceae)

Buddleja macrostachya （Buddlejaceae） is a widespread shrub native to the Sino-Himalayan mountains and beyond. It has been found to occur at two ploidy levels, hexaploid, 2n=6x=114 and dodecaploid, 2n= 12x=228. To determine if morphological characters might be used as indicators of ploidy levels, we measured floral and fruit length, relative and absolute leaf size, trichome density on both leaf surfaces, and stomatal density and length in different populations orB. macrostachya. In general, flower and fruit length, absolute leaf size, and stomatal length in,eased with an increase at ploidy level （P〈0.01）, whereas adaxial cell and stomatal density decreased with an increase at ploidy level （P〈0.01）. We found no conspicuous differences in relative leaf size （P〉0.05） in different populations. Other characters studied such as trichome type, cuticular membrane and ornamentation of stomata, cell and stomatal shape, and anticlinal wall pattern were quite constant in this species. Thus it appears that flower and fruit length, absolute leaf size, and stomatal frequency and length can be used to distinguish hexaptoid from dodecaploid cytotypes either in the field or in herbarium specimens.

ALTERATION OF HB-EGF IN PSORIATIC EPIDERMIS WITH THE TREATMENT OF RETINOID ACID

Objective To investigate the mechanism of tazarotene in active psoriasis vulgaris. Methods HB EGF protein in active psoriatic lesions before and 10 days after the treatment of tazarotene was detected by immunohistochemistry. Results There was nearly no expression of HB EGF in psoriatic lesions (9.1%), but after the treatment by tazarotene, there was expression of HB EGF not only in basal layer (95.5%), but also focal expression in suprabasal layers of epidermis (77.3%) . Conclusion Tazarotene inhibit proliferation and induce apoptosis of keratinocytes through upregulating expression of HB EGF in psoriatic epidermis.

Wound Healing: From Epidermis Culture to Tissue Engineering

The skin is the largest organ of the individual, being the interface between the body and the microenvironment. In severely burned patients and other diseases, the physiological processes of wound healing are not sufficient to complete the closure of their wounds. The in vitro culture of autologous epidermis, which has represented the beginning of Tissue Engineering, is a valuable tool for the treatment of these patients. Keratinocytes can be cultured and stratified in vitro, and an entire epidermal sheet can be obtained. The epidermis cells can be amplified in the laboratory from a skin sample to obtain a surface equivalent to that required for each patient. This technology was first used clinically in 1981 and in Argentina since 1991. Wound repair is a complex process that involves dermal and epidermal cells, extracellular matrix, soluble factors and the sum of interactions between them, providing physical, biological and chemical keys capable of guiding cell function. Seeking to improve the results obtained with cultured epidermis, tissue engineering was directed towards the development of substitutes that not only involve epidermis but also the dermal component. The tissue engineered skin and its therapeutic applications reported in this review demonstrate the feasibility and effectiveness of these approaches. It represents a clear benefit in wound healing. Now, focus must be directed on the development of new scaffolds, developed by different technologies, such as polymer science, or nanotechnology, able to be used as templates to direct the growth of cells, in an attempt to better regenerate the lost skin.

Comparative Morphology of the Leaf Epidermis in <i>Ligusticum</i>(Apiaceae) from China

To investigate the taxonomic value of leaf epidermal characters in developing a classification for Ligusticum (Apiaceae), thirty-eight species (including a cultivar) of the genus were examined using both light and scanning electron microscopy. Our results show that the infrageneric classification of Ligusticum based on the characters of involucel bracteoles, mericarps, and pollen grains was not supported as few epidermal characters were relatively constant at section level. Evidence from leaf epidermis, similar to that from molecular and morphological data, supports the separation of Tilingia (i.e. L. ajanense and L. tachiroei) from Ligusticum. Ligusticopsis was found to be indistinguishable from Ligusticum in epidermal characters. Furthermore, results from epidermal analysis, together with that from cytological evidence, fruit morphology as well as molecular phylogenetics suggest that L. delavayi should be transferred out of Ligusticum.

Ultrastructure of Bat (Pipistrellus kuhlii) Epidermis with Emphasis on Terminal Differentiation of Corneocytes

The ultrastrncture of the skin of air-adapted mammals （bats） is not known. The study at the electron microscope of the skin of the back and the flying membrane of Pipistrellus kuhlii showed that the thickness of the epidermis is very low （10- 12μm）, and that 1 - 2 flat spinosus cells are present beneath the stratum corneum which is formed by very thin corneoeytes that resemble those of avian apteric epidermis. The stratum granulosum is discontinuous and few small （less than 0.3μm large） keratohyalin granules are present. The epidermis is reduced to one flat basal layer in contact with the stratum corneum in many areas of the flying membrane. Transitional corneoeytes are almost absent suggesting that the process of eornification is very rapid. In the basement membrane numerous hemidesmosomes are present and form attachment points for the dense dermis underneath. Numerous collagen fibrils directly contact with the hemidesmosomes and the dense lamella of the basement membrane. Sparse elastic fibrils allow the stretching of the epidermis during flight and the rapid folding of the epidermis after flying without damaging the epidermis. Like in avian epidermis, the production of lipids is high in bat keratinocytes, and multilamellar bodies discharge lipids extra- and intra-cellularly. This may compensate the lack of a thick fat layer in the dermis of the flying membrane as lipids may help in thermical insulation against the cooling air currents flowing on the bat skin during flight. Fur hairs are very thin （4 - 7 μm）, and they have an elaborated cuticle made of pointed expansions similar in texture with that of the cortex. Cuticle ceils form hook-like grasping points that allow to keep hairs stuck together. In this way the pelage remains compact in order to maintain body temperature.

The ion balance of Shotokuseki extract promotes filaggrin fragmentation and increases amino acid production and pyrrolidone carboxylic acid content in three-dimensional cultured human epidermis

Natural moisturizing factor(NMF)in the stratum corneum contributes to the retention of moisture there.The purpose of this study was to determine the penetration of ions in Shotokuseki extract(SE)into the three-dimensional cultured epidermis and the effect of NMF on the biosynthesis of amino acids and pyrrolidone carboxylic acid formation.Vari-ous ions,amino acids and pyrrolidone carboxylic acid were quantified by inductively coupled plasma mass spectrom-etry,fully automatic amino acid analyzer or high-performance liquid chromatography(HPLC)in three-dimensional cultured epidermis after application of SE.Gene expression levels of profilaggrin,calpain1,caspase14,and bleomycin hydrolase,which are involved in NMF production,were determined by reverse-transcription qPCR and bleomycin hydrolase activity was determined by aminopeptidase assay.The application of SE increased Na,K,Mg,Ca,Al,and Fe levels in three-dimensional cultured epidermis.The mRNA levels of the starting material of amino acid synthesis profilaggrin,and calpain1 and bleomycin hydrolase,which are involved in its fragmentation,increased.The activity of bleomycin hydrolase also increased.Furthermore,the levels of amino acids and pyrrolidone carboxylic acid increased in the three-dimensional cultured epidermis.This suggests that the ionic composition of SE may be involved in its moisturizing effect on the stratum corneum.

Exogeneous energy supply and excitability of cells in embryonic atypical epidermis of Cynops cultured in vitro

Cells of in vitro cultured epidermis explants of ectoderm isolated at early gastrula stage,showed only weak excitability or even non-excitable at 6V when examined electrophysiologically.If non-excitable explants were treated with 100 mM glucose,the action potential (AP) appeared and within 1 hr reached its maximum.At the same time,their stimulus threshold became lowered gradually.And,if the glucose was washed out,AP gradually disappeared.If explants were treated with glucose of different concentrations,the percentage of explants which displayed AP increased with the increase of glucose concentration.When explants with approximately the same original stimulus threshold were treated with glucose of different concentrations,the stimulus threshold became lowered more in the more concentrated solution.If explants with different original stimulus thresholds were treated with glucose of the same concentration,the lowering of stimulus threshold was more obvious in those with higher original stimulus threshold.Other energy supplying substances used showed similar effect.

Detergent-Induced Changes in the Protein Constituents of Various Cell Types of Opercular Epidermis of Rita rita

Fish (Rita rita) were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, at a concentration of 6.9mg/liter (96-hr LC_(50) of the detergent).A series of histochemical techniques, used in this study for the demonstration of various protein constituents, indicated a gradual decrease in the intensity of staining reactions of the cytoplasmic material, suggesting a loss of protein moieties from the club cells and the epithelial cells of the opercular epidermis as a result of detergent exposure. 1990 Academic Press.Inc.

Wound Closure on the Neonatal Rat Skin II. The Potential Ability of Epidermis to Close Small-Sized Wounds Independently of the Underlying Dermis

Reepithelialization of skin which comprises epidermis and dermis has not been fully elucidated due to the complexity of the participants as well as the interactions therein. In this study, the intrinsic roles and behaviors of epidermis itself during wound closure on neonatal rat skin were explored by developing and utilizing a novel in vivo wound model, termed “shallow incisional wound” in which the injury of dermis was minimized. The shallow wounds were closed by 12 h postwounding (PW) by the migration of the wound-marginal epidermal sheets in which activated myosin light chain (p-MLC) was predominantly detected at the lateral plasma membrane of individual cells. By local administration of Rho-associated protein kinase (ROCK) inhibitor Y27632, p-MLC disappeared at the wound margin and wounds were not closed by 12 h PW. Inhibition of Rac 1 by NSC23766 also resulted in hold of wound closure by 12 h PW, though NSC23766 somewhat slowly acted on p-MLC expression. These results suggest that, without joining of dermis, epidermal cells have a potential ability of closing wounds by active epithelial sheet movement integrated by Rho family small GTPases-dependent extension and contraction of the individual cell bodies.

Wound Closure on the Neonatal Rat Skin I. The Modulation of the Thickness of Epidermis at the Closing Incisional Wounds

Full-thickness incisional wounds were made on the dorsal skin of 1-day-old rats to elucidate the mechanism of the fluctuation of the epidermal thickness after the wound closure. The thickness of the epidermis covering the wound reached a peak around 96 h post-wounding (PW), and became thinner thereafter. The analyses of the cell proliferation and apoptosis at the epidermal wound regions revealed that the rate of TUNEL-positive cells that displays the cells undergoing apoptosis increased as the epidermis became thinner around 120 h PW. Next, immunohistochemical analyses using antibodies against keratinocyte differentiation marker proteins indicated that the delay or interruption of the spinous to granular transition from 96 to 120 h PW might result in the epidermal thickening in the wound region. Third, the region undyed with anti-caspase-14 antibody extended downward in the thickened epidermis by 96 h PW, and in turn, it became intensely and widely stained with this antibody in the thinning epidermis by 120 h PW. Taken together, it is likely that the delay and acceleration of the terminal differentiation, including cornification of the epidermal keratinocytes may coordinately cause the fluctuation of the thickness of the epidermis at the wound site in rat neonates.

Biodiversity of the Micro-morphologies of the Petal Epidermis of Angiosperms &Their Scientific Aesthetics, Quasi-Geometry

The micro-morphologies and biodiversities of the epidermis of flower petals of angiosperms were reported for the first time. By manual slicing anatomy and microscopic photography technique, the micro-morphologies of the upper and lower epidermis of petals of some common ornamental flowers in Kunming were studied, and the biodiversities were discovered. The results showed these much-varied pigment cells appeared not only a new compensation to anatomy, but a new criteria to taxonomy, so that a brand new research field of “Cell Taxonomy” was established instead of the current “Chromosome Taxonomy” widely used in phytosystematics research. Furthermore, the most interesting and significant phenomena was their scientific aesthetics: these pigment cells of flower petals were quite special, planary, far different from the ordinary plant cells in plant organs & tissues. By comparison to ordinary geometry, these colorful cells of the fresh flower petals could be described as “Quasi-geometry” for their special origin and micro-morphological characteristics. As for the aspect of art, it was quite similar to “Quasi-crystal” discovered by Daniel Schechtman, so that the art future was discussed, obviously another new epoch of scientific-art history began.

The intrinsic or the extrinsic pathways of apoptosis in the epidermis after cladribine application?

Purpose: This study was aimed to assess the expression of caspase 8 and caspase 9 in the epidermis, during apoptosis after cladribine administration. Materials and Methods: The experiment was carried on 10 Wistar rats. The animals were placed into 2 groups: control group and experimental group. Animals in the control group, in addition to standard feed and water, were injected with a physiological salt in a quantity corresponding to the drug dosage, over the course of the experiment. The experimental group animals were treated with cladribine in the dose of 0.07 mg/kg/24h, for 6 consecutive days in the morning, in 3 cycles with a 5-week gap in administering the drug. After the completion of the experiment, the animals were decapitated, and full thickness slices of skin were taken from all the rats for immunohisto- chemical study. The results of the statistical surveys were analysed in Statistica 10.0. The difference in intensity of expression of caspase 9 and caspase 8 in the groups were investigated using the Chiquadrat test. Statistical significance was considered at p < 0.05. Results: The statistical analysis found significant correlation in expression of caspase 9 between examined groups (p < 0.0001). There were no statistical relationships in the presence of the expression of caspase 8 between examined groups (p = 0.0526). Conclusion: Our findings suggest that mechanism of apoptosis in the rats’ epidermis, induced by cladribine given in the scheme used in the treatment of MS in humans, involves caspase 9 activity. This means that 2-CdA initiates the intrinsic apoptosis pathway.

Relationship Between Micromorphological Structure of Leaf Epidermis and Drought Resistance in Callisia repens

[Objectives]To discuss the relationship between left epidermis structures and drought resistance.[Methods]The leaf epidermis of Callisia repens was studied by optical microscope.[Results]The upper and lower epidermal cells of the leaves of Callisia repens arranged closely,and no cell gap was arranged.The morphology of the epidermal cells was hexagonal,few pentagon or heptagon,the equivalent elliptical aspect ratio was 1.20,the vertical wall was straight and there was no stomatal distribution.Compared with the epidermal cells,the morphology of the lower epidermal cells was irregular.The equivalent elliptic aspect ratio was 1.35,and the vertical wall was smooth and curved.The mean oval aspect ratio of the stomatal guard cells was 1.42,the average stomatal density was 11.79/mm 2,and the average stomatal index was 17.21.[Conclusions]These characteristics provide the theoretical basis for the drought resistance of Callisia repens and the ornamental plants as roof greening.

Differentiation of human epidermis-derived mesenchymal stem cell-like pluripotent cells into neural-like cells in culture and after transplantation

Skin is the largest organ of the human body and a possible source of stem cells for research and cell-based therapy. We have isolated a population of mesenchymal stem cell-like pluripotent cells from human epidermis, termed human (h) EMSCPCs. This preliminary study tested if these hEMSCPCs can be induced to differentiate into neural-like cells. Human EMSCPCs were first cultured for four to seven days in a serum-free neural stem cell (NSC) medium for pre-induction. During pre-induction, hEMSCPCs coalesced into dense spheres that resembled neural rosettes. In the presence of a conditioned differentiation medium, pre-induced cells took on the morphological characteristics of neural cells, including slender projections with inflated or claw-like ends that contacted the soma or projections of other cells as revealed by confocal microscopy. Moreover, these differentiating cells expressed the neural-specific markers β-III tubulin, MAP2, GFAP, and synapsin I as evidenced by immunocytochemistry. Both pre-induced hEMSCPCs and uninduced hEMSCPCs were labeled with CM-DiI and transplanted into the vitreous cavities of nude mice. Transplanted cells were examined four weeks later in frozen eyeball sections by immunofluorescence staining, which demonstrated superior retinal migration and neural differentiation of pre-induced cells. Our study is the first to demonstrate that hEMSCPCs possess the capacity to differentiate into neural-like cells, suggesting potential uses for the treatment of retinal diseases such as age-related macular degeneration.

Histopathological Changes in the Epidermis of the Air Breathing Catfish Heteropneustes fossilis Exposed to Sublethal Concentration of Mercuric Chloride

Histopathological alterations induced by the sublethal concentration of (0.03 ppm) mercuric chloride solution on the epidermis of the fresh-water catfish Heteropneuates fossilis have been studied. It induces slow but significant histopathological changes in the various cellular components of the epidermis. It induces vacuolization, necrosis and pycnosis of the nuclei of the epithelial cells which subsequently shed. Loosening of epithelial cells of the outermost and middle layers following degeneration of the intercellular material and widened intercellular spaces is another important alteration. Prolonged mercury treatment also causes a gradual decrease in staining intensity for sulphated glycosaminoglycans in the outer border of the most superficial layer epithelial cells. The glandular elements (club cells and mucocytes) also get affected, showing cyclic degeneration followed by regeneration.