A specialized tissue type, the keratinizing epithelium, protects terrestrial mammals from water loss and noxious physical, chemical and mechanical insults. This barrier between the body and the environment is constantly maintained by reproduction of inner living epidermal keratinocytes which undergo a process of terminal differentiation and then migrate to the surface as interlocking layers of dead stratum corneum cells. These cells provide the bulwark of mechanical and chemical protection, and together with their intercellular lipid surroundings, confer water-impermeability. Much of this barrier function is provided by the cornified cell envelope (CE), an extremely tough protein/lipid polymer structure formed just below the cytoplasmic membrane and subsequently resides on the exterior of the dead cornified cells. It consists of two parts: a protein envelope and a lipid envelope. The protein envelope is thought to contribute to the biomechanical properties of the CE as a result of cross-linking of specialized CE structural proteins by both disulfide bonds and N(epsilon)-(gamma-glutamyl)lysine isopeptide bonds formed by transglutaminases. Some of the structural proteins involved include involucrin, loricrin, small proline rich proteins, keratin intermediate filaments, elafin, cystatin A, and desmosomal proteins. The lipid envelope is located on the exterior of and covalently attached by ester bonds to the protein envelope and consists of a monomolecular layer of omega-hydroxyceramides. These not only serve of provide a Teflon-like coating to the cell, but also interdigitate with the intercellular lipid lamellae perhaps in a Velcro-like fashion. In fact the CE is a common feature of all stratified squamous epithelia, although its precise composition, structure and barrier function requirements vary widely between epithelia. Recent work has shown that a number of diseases which display defective epidermal barrier function, generically known as ichthyoses, are the result of genetic defects of the synthesis of either CE proteins, the transglutaminase 1 cross-linking enzyme, or defective metabolism of skin lipids.
Animal ; Cell Membrane/metabolism ; Epidermis/metabolism* ; Epidermis/chemistry* ; Human ; Ichthyosis/metabolism ; Ichthyosis/genetics ; Keratinocytes/metabolism* ; Keratinocytes/chemistry ; Membrane Lipids/metabolism* ; Membrane Proteins/metabolism* ; Protein-Glutamine gamma-Glutamyltransferase/metabolism

OBJECTIVETo accumulate taxonomic data of the leaf epidermal features of the medicinal species of Euonymus.

METHODTwenty-nine materials of 21 taxa (including 16 species, 4 varieties and 1 form) representing 5 sections of Euonymus are examined by using both of light microscopy and scanning electron microscopy.

RESULTThe form of epidermal cells in Euonymus is usually polygonal or irregular. The stomata were anomocytic in all the species examined except E. maackii and E. bungeanus var. semipersistens. Stomatal types of all species studied may be anomocytic, anisocytic, cycolocytic or the transitional types among them.

CONCLUSIONThe results show that some characteristics (including cuticular membrane, shape of guard cells, inner margin of outer stomatal rim, outer stomatal rim and stomata type) of the leaf epidermis can provide some anatomical evidence for the classification. The characteristics of leaf epidermis support following treatments: E. acanthocarpus var. longipes, E. acanthocarpus var. scandens and E. acanthocarpus var. sutchuanensis should be merged into E. acanthocarpus; E. bungeanus var. semipersistens should be merged into E. maackii; E. hamiltonianus f. lanceifolius should be merged into E. hamiltonianus.

China ; Euonymus ; chemistry ; classification ; Microscopy ; Microscopy, Electron, Scanning ; Plant Epidermis ; chemistry ; classification ; Plant Leaves ; chemistry ; classification ; Plant Stomata ; chemistry ; classification ; Plants, Medicinal ; chemistry ; classification

OBJECTIVETo investigate the Raman spectral characteristics of oral squamous cell carcinoma, high-grade epithelial dysplasia and normal mucosa.

METHODSFifty- six fresh samples of oral carcinoma, 50 of high-grade epithelial dysplasia and 32 of normal mucosa were collected. The i-Raman spectrometer with an optical fiber tube was applied to acquire Raman spectrum. The diagnostic model established by principle component analysis (PCA) and discriminant function analysis (DFA) was used to analyze and classify the spectra of different samples.

RESULTSThere were significant differences among the Raman spectra of these samples. Compared with the spectra of normal mucosa, the spectra of oral carcinoma and dysplasia showed strong peaks which were contributed to nucleic acids, proteins and lipids. The diagnostic models established by PCA-DFA could successfully classify these Raman spectra of different samples with a high accuracy of 96.4% (133/138). The model was evaluated by 'Leave one out' cross-validation and reached a high accuracy of 92.8% (128/138).

CONCLUSIONSThe proliferation and metabolism of oral squamous cell carcinoma and epithelial high-grade dysplasia are more active than normal mucosa. The diagnostic models established by PCA-DFA can classify these Raman spectra of different samples with a high accuracy.

Carcinoma, Squamous Cell ; chemistry ; pathology ; Discriminant Analysis ; Epidermis ; chemistry ; pathology ; Humans ; Mouth Mucosa ; chemistry ; Mouth Neoplasms ; chemistry ; pathology ; Mucous Membrane ; chemistry ; Principal Component Analysis ; Spectrum Analysis, Raman

OBJECTIVETo explore the relationship between epidermal stem cells and the developing process of sweat gland in human fetal skin, so as to obtain a hint for future induction of epidermal stem cells to differentiate into sweat gland cells.

METHODSTotal layer of human skin from the back of fetus at gestational ages from 11 to 31 weeks, obtained from spontaneous abortion was routinely examined. The expressions of beta1 integrin and keratin 19 in sweat gland cords or buds and mature sweat gland cells were dynamically observed with SP immunohistochemical technique. The development and maturation of sweat gland were identified by the positive staining of keratin 8 with immunohistochemistry.

RESULTSIt was revealed by histologic observation that basal layer cells of the primary epidermal ridge exhibited focal aggregation and formed hillocks at 16 gestational weeks. The hillocks of cells then migrated downward as cords into the dermis during 18 - 20 gestational weeks. Then, the end part of the cell cord developed into a round lump of twining cords assuming the mature sweat gland. The expressions of beta1 integrin and keratin 19 were found not only in sweat gland cords and buds but also in the mature cells and lasted throughout the total period of sweat gland development. The expression of keratin 8 in sweat gland buds started since 14 - 16 gestational weeks and maintained thereafter.

CONCLUSIONThe sweat gland started to develop during 14 - 16 gestational weeks and matured at 24 weeks. During the development process of sweat gland, epidermal stem cells were considered to be the key source.

Aborted Fetus ; Epidermis ; chemistry ; cytology ; embryology ; Humans ; Immunohistochemistry ; Integrin beta1 ; analysis ; Keratin-8 ; Keratins ; analysis ; Skin ; chemistry ; embryology ; Stem Cells ; chemistry ; cytology ; Sweat Glands ; chemistry ; embryology

Lymphomatoid papulosis is a strange disease; clinically benign, histologically malignant. Clinically, it may simulate pityriasis lichenoides et varioliformis acuta. The diagnosis is based on the typical histopathological features suggestive of malignant lymphoma, due to the presence of polymorphous lymphoid infiltrate consisting of small lymphocytes intermingled with conspicuous large atypical cells. We experienced a case of lymphomastoid papulosis in 35-year-old woman. Initially, her skin lesions developed as erythematous papules on the extremities, gradually spreading centrifugally with a tendency to involute slowly without treatment, leaving brown wrinkled surface and shallow ulceration. These skin lesions tended to become worse in warm weather and better in cold weather. At first visit, multiple erythematous grouped, ulcerated papules and nodules are seen. 18 months after first visit, most skin lesions are regressed except 5 erythematous pinhead sized papules on right leg in spite of no treatrnent. Labcratory examiniations of CBC, VDRL, urinatlysis, blood chemistry and chest X-ray were all within normal limits. Histopathologically there were hygerkeratosis, mild acanthosis, exocytosis in epidermis, and numerous lymphoid cells were infiltrated especially on perivascular and periappendegeal area, and many atypical cells showing hyperchromatic nuclei, kidney-shaped nuclei and mitotic figures in dermis.
Adult ; Chemistry ; Dermis ; Diagnosis ; Epidermis ; Exocytosis ; Extremities ; Female ; Humans ; Leg ; Lymphocytes ; Lymphoma ; Lymphomatoid Papulosis* ; Pityriasis Lichenoides ; Skin ; Thorax ; Ulcer ; Weather

This study was performed to determine the ability of eliminating sodium nitrite and blocking nitrosamine synthesis by anthocyanin from the skin of Alpinia galanga. purified by macroporous resin. The test was conducted under the condition of the simulated human gastric juice (pH 3.0, 37 degrees C) with VitC as positive control. The results showed that the max capability of eliminating sodium nitrite was 87.14%, which is 1.6 times sronger than that of VitC, and the max capability of blocking nitrosamine synthesis was 97.82%, which is 8 times sronger than that of VitC.
Alpinia ; chemistry ; Anthocyanins ; isolation & purification ; pharmacology ; Antioxidants ; pharmacology ; Ascorbic Acid ; pharmacology ; Gastric Juice ; chemistry ; Humans ; Hydrogen-Ion Concentration ; Hydrolysis ; drug effects ; Nitrosamines ; antagonists & inhibitors ; metabolism ; Plant Epidermis ; chemistry ; Sodium Nitrite ; metabolism

OBJECTIVETo investigate the different location and the expression characteristics of epidermal stem cells in normal adult skin and scar tissue.

METHODSSkin tissue specimens were harvested from the corresponding sites from 6 healthy volunteers and from scar tissue of 6 patients 1 year after major deep burn. beta1 integrin and keratin 19 (K19) were employed as the biochemical markers for stem cells and transit amplifying cells identification and keratin 14 (K14) and keratin 10 (K10) as markers for post-mitotic cells and terminally differentiated cells respectively. Integrin and keratin were determined by Elivision two-step immunohistochemistry.

RESULTSThe expression of beta1 integrin and the K19 positive cell count in the epithelial basal layers of scar tissue were evidently decreased and weakened than those in normal adult healthy skin. Furthermore, the positive cells expressing K14 in epidermis of scar tissue were only located in 2 - 3 layers of basal epidermis, and their number was much less than that in normal adult skin. Whereas the cells positively expressing K10 were distributed wider in area than that in normal healthy skin. The epidermal stem cells and transit amplifying cells in scar epidermis were much less in number than that in normal skin. The differentiation process of scar epidermal stem cells was different from that of normal skin. And the proportions of post-mitotic cells and terminally differentiated cells were abnormal.

CONCLUSIONThe results indicated that the self-renewal ability of the scar epidermis was decreased, and the differentiation process of it was in disorder, which may be a reason for the abnormality of structure and function of the epidermis in scar, and a reason for the decreased ability of wound healing of scar tissue.

Adult ; Burns ; complications ; metabolism ; pathology ; Cicatrix ; etiology ; metabolism ; pathology ; Epidermis ; chemistry ; cytology ; Humans ; Immunohistochemistry ; Integrin beta1 ; analysis ; Keratin-10 ; Keratin-14 ; Keratins ; analysis ; Middle Aged ; Skin ; chemistry ; cytology ; Stem Cells ; chemistry ; cytology

BACKGROUNDKeratinocyte growth factor (KGF) significantly influences epithelial wound healing. The aim of this study was to isolate KGF phage model peptides from a phage display 7-mer peptide library to evaluate their effect on promoting epidermal cell proliferation.

METHODSA phage display 7-mer peptide library was screened using monoclonal anti-human KGF antibody as the target. Enzyme linked immunosorbent assay (ELISA) was performed to select monoclonal phages with good binding activity. DNA sequencing was done to find the similarities of model peptides. Three-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, immunofluorescence assay and quantitative real-time PCR analysis were employed to evaluate the effect of the phage model peptides on epidermal cells.

RESULTSThirty-three out of fifty-eight (56.9%) of the isolated monoclonal phages exhibited high binding activity by ELISA. Ten of fifteen obtained phage model peptides were similar to KGF or epidermal growth factor (EGF). MTT assay data showed that four (No. 1 - 4) of the ten phage model peptides could promote epidermal cell proliferation. The expression of keratinocyte growth factor receptor (KGFR) mRNA in the KGF control group and the two phage model peptide groups (No. 1 and No. 2) increased. Expression of c-Fos mRNA and c-Jun mRNA in the KGF control group increased, but did not increase in the four phage model peptide groups (No.1 - 4).

CONCLUSIONFour phage model peptides isolated from the phage display 7-mer peptide library can safely promote epidermal cell proliferation without tumorigenic effect.

Cell Proliferation ; drug effects ; Cells, Cultured ; Enzyme-Linked Immunosorbent Assay ; Epidermis ; cytology ; Fibroblast Growth Factor 7 ; chemistry ; pharmacology ; Humans ; Peptide Library ; Peptides ; chemistry ; pharmacology ; Polymerase Chain Reaction ; Receptor, Fibroblast Growth Factor, Type 2 ; genetics

Ceramides are the main lipid component maintaining the lamellae structure of stratum corneum, as well as lipid second messengers for the regulation of cellular proliferation and/or apoptosis. In our previous study, psoriatic skin lesions showed marked decreased levels of ceramides and signaling molecules, specially protein kinase C-alpha (PKC-alpha) and c-jun N-terminal kinase (JNK) in proportion to the psoriasis area and severity index (PASI) scores, which suggested that the depletion of ceramide is responsible for epidermal hyperproliferation of psoriasis via downregulation of proapoptotic signal cascade such as PKC-alpha and JNK. In this study, we investigated the protein expression of serine palmitoyltransferase (SPT) and ceramidase, two major ceramide metabolizing enzymes, in both psoriatic epidermis and non-lesional epidermis. The expression of SPT, the ceramide generating enzyme in the de novo synthesis in psoriatic epidermis, was significantly less than that of the non-lesional epidermis, which was inversely correlated with PASI score. However, the expression of ceramidase, the degradative enzyme of ceramides, showed no significant difference between the lesional epidermis and the non-lesional epidermis of psoriatic patients. This might suggest that decreased expression of SPT protein is one of the important causative factors for decreased ceramide levels in psoriasis.
Adolescent ; Adult ; Amidohydrolases/*biosynthesis/metabolism ; Apoptosis ; Cell Proliferation ; Ceramidases ; Ceramides/chemistry ; Child ; Epidermis/metabolism ; Female ; Humans ; JNK Mitogen-Activated Protein Kinases/metabolism ; Male ; Models, Biological ; Protein Kinase C-alpha/metabolism ; Psoriasis/*blood/diagnosis ; Serine C-Palmitoyltransferase/*biosynthesis

Disseminated superficial porokeratosis (DSP) is a rare cause of secondary cutaneous amyloidosis. An 83-year-old male patient showed an increase in both size and number of DSP lesions after contracting pulmonary tuberculosis. The DSP lesions of the patient consisted of numerous annular eruptions on both sun-exposed and sun-protected areas, which occurred over a period of 20 years. Multiple skin biopsies were taken from normal or lesional/sun-exposed or sun-protected skin samples. Histopathologic examination included routine H+ACY-E stains, Congo red stains, thioflavin-T stains and anticytokeratin antibodies (AE1, AE3). And the results were as follows+ADs- 1) Positive staining with Congo red and thioflavin-T indicated an amyloid nature for the deposits, 2) confinement of the amyloid deposition just below the lesional epidermis (while sparing the neighboring uninvolved or distant normal skin) indicated some role of the lesional epidermis, and 3) positive staining with AE3 further indicated an epidermal origin-type II epithelial keratin-of the amyloid. We present a case of DSP with a local amyloid deposit, characterized by association of positive familial background, severe pruritus and pulmonary tuberculosis.
Aged ; Aged, 80 and over ; Amyloid/analysis ; Amyloidosis/etiology+ACo- ; Case Report ; Congo Red ; Dyes ; Epidermis/chemistry ; Human ; Male ; Porokeratosis/complications+ACo- ; Pruritus/etiology ; Skin Diseases/etiology+ACo- ; Staining and Labeling ; Thiazoles ; Tuberculosis, Pulmonary/complications