PURPOSE: This study was carried out to clarify the histological characteristics of the interface of the corneal stroma and Descemet's membrane of the human eye. METHODS: Nighteen donor eyes without corneal pathology were examined by scanning and transmission electron microscopy. The Descemet's membrane including the corneal endothelium was cheked for scanning electron microscopy. The junctional characteristics of the posterior corneal stroma and Descemet's membrane was examined by transmission electron microscopy. RESULTS: The scanning electron microscopy showed that collagen sheet faced each other at the right angle near the Descemet's membrane and penetrated the Descemet's membrane with the irregular arrangement. The transmission electron microscopy showed that the electron-dense collagen filaments extended to the posterior stroma from Descemet's membrane. The arrangement of electron-dense collagen filaments paralleled with the arrangement of the collagen fibrils of the posterior stroma. CONCLUSIONS: The interface of the corneal stroma and Descemet's membrane was composed of two-typed extracellular materials without the intercellular specificatons.
Collagen ; Corneal Stroma* ; Descemet Membrane* ; Endothelium, Corneal ; Humans ; Microscopy, Electron ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Pathology ; Tissue Donors

BACKGROUNDTrichosporon asahii (T. asahii) is one of the most important pathogenic fungus in the genus of trichosporon. Although the species identification of T. asahii was based upon the complicated results of morphologic, biochemical and biologic examination, the morphology characteristic is still the first clue to the species. Some common structures of T. asahii had been described such as arthrofilaments and arthroconidia, but other important structures of T. asahii were unclear.

METHODSSix strains of T. asahii were incubated on the slant and micro culture of Sabouraud's dextrose agar at 30 degrees C for 7 days. Samples were fixed using 2% paraformaldehyde and 2.5% glutaraldehyde. T. asahii was observed under scanning electron microscope and transmission electron microscope.

RESULTSThe detailed characteristics of the diverse sites of germination, as well as some uncommon structures such as giant cell, sarcinate, and club-shaped macroconidia, were presented. The pseudohyphae of T. asahii were noted to produce true hyphae, either along the longitude axis or on the flank. T. asahii was noted to have blastic and thallic conidiation. Digitated branches, trichoid structures and septa inside the spores were detected.

CONCLUSIONThese results may add our knowledge to the structure and development of T. asahii.

Lung fluke, Paragonimus heterotremus, is a flatworm causing pulmonary paragonimiasis in cats, dogs, and humans in Southeast Asia. We examined the ultrastructure of the testis of adult P. heterotremus with special attention to spermatogenesis and spermiogenesis using scanning and transmission electron microscopy. The full sequence of spermatogenesis and spermiogenesis, from the capsular basal lamina to the luminal surface, was demonstrated. The sequence comprises spermatogonia, spermatocytes with obvious nuclear synaptonemal complexes, spermatids, and eventual spermatozoa. Moreover, full steps of spermatid differentiation were shown which consisted of 1) early stage, 2) differentiation stage representing the flagella, intercentriolar body, basal body, striated rootlets, and electron dense nucleus of thread-like lamellar configuration, and 3) growing spermatid flagella. Detailed ultrastructure of 2 different types of spermatozoa was also shown in this study.
Animals ; Male ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Paragonimus/*physiology/*ultrastructure ; Spermatogenesis ; Spermatozoa/ultrastructure ; Testis/ultrastructure

OBJECTIVETo design a kind of biomimetic polypeptide of dentin matrix protein-1 (DMP-1), which can bind to dentine collagen fibers and initiate mineralization.

METHODSA novel polypeptide was developed by connecting the collagen binding domain of DMP-1 "DSESSEEDR" to the hydrophilic C-terminal of amelogenin "TKREEVD". The polypeptide was synthetically prepared by standard solid-phase peptide synthesis. Human dentine slices were completely demineralized by hydrochloric acid to expose the dentine collagen. Fluorescein isothiocyanate coupled polypeptide was applied to the exposed dentine collagen. Fluorescent microscopy was used to examine the polypeptide specially bond to the dentine collagen. Nucleation and growth of hydroxyapatite was initiated by immersing the polypeptide into calcium chloride and sodium hypophosphate solutions respectively. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and selected area diffraction (SAD) were used to examine the hydroxyapatites formed. RESULTS Fluorescent dentine collagen was identified in the demineralized dentine specimens. Nucleation and growth of crystals were detected after immersing the polypeptide into calcium chloride and sodium hypophosphate solutions by SEM and TEM. SAD confirmed the crystals were hydroxyapatites.

CONCLUSIONThe polypeptide of "DSESSEEDRTKREEVD" can simulate DMP-1 binding collagen and initiate hydroxyapatite nucleation and growth. It may be a potential molecular tool for dentine remineralization.

OBJECTIVETo observe the ultrastructural features of taste pores and taste pits of human taste buds.

METHODSThree samplers obtained randomly from adults were divided into two perts, and transmission electron microscopy and scanning electron microscopy were used to observe the fine structure of taste buds in human circumvallate papillae.

RESULTSThe longer diameter of the taste pores was 1.02 - 7.36 microm, and most of taste pores contained no taste hair and dense material, and the profile of taste pit was triangular.

CONCLUSIONSTaste hair and dense material were seldom observed in most of taste pores.

Anatomical examinations on Bruch's membrane have almost been by light microscopy or transmission electron microscopy. Scanning electron microscopy allowed us to evaluate surface features topographically. Each layer of Bruch's membrane was exposed sequentially to mechanical or enzymatic treatment of the retinal pigment epithelium choroid complex from human cadavar eye. The authors examined the surface features of the membrane by dry-cracking scanning electron microscopy. The basement membrane of retinal pigment epithelium appeared like a smooth thin plastic membrane which was framed by collagen fibers. The inner collagenous layer was composed of many collagen fiber bundles which were placed in order and the ground substance between them was not visible. Elastic layer of Burch's membrane appeared to be coarse and fine fibers matted together by some amorphous substance. This layer had many openings on its solid sheet and the outer collagenous zone was visible though these openings.
Basement Membrane ; Bruch Membrane* ; Choroid ; Collagen ; Humans* ; Membranes ; Microscopy ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Plastics ; Retinal Pigment Epithelium

BACKGROUND: Genetic factors account for the majority of differences in skin color and hair morphology across human populations. Although many studies have been conducted to examine differences in skin color across populations, few studies have examined differences in hair morphology. OBJECTIVE: To investigate changing of integral hair lipids after ultraviolet (UV) irradiation in three human ethnic groups. METHODS: We studied the UV irradiation induced hair damage in hairs of three human populations. UV irradiation had been performed with self-manufactured phototherapy system. Damaged hair samples were prepared at 12 and 48 hours after UVA (20 J/sec) and UVB (8 J/sec) irradiation. We evaluated the changes of hair lipid using scanning electron microscopy (SEM), transmission electron microscopy (TEM), lipid TEM and HP-TLC. After UV irradiation, hair surface damage was shown. RESULTS: African hair showed more severe damage on hair surface than others. The lipid compositions across human populations were similar, but Asian hair had more integral hair lipids than other groups as a whole. Especially, free fatty acid contents were higher than other lipids. After UV irradiation, lipid contents were decreased. These patterns were shown in all human populations. Asian hair has more integral hair lipid than European or African hair. After UV irradiation, European and African hair samples exhibited more damage because they have less integral hair lipids. However, Asian hair samples have less damage. CONCLUSION: We conclude that integral hair lipid may protect the hair against the UV light.
Asian Continental Ancestry Group ; Ethnic Groups ; Hair ; Humans ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Phototherapy ; Skin ; Ultraviolet Rays ; Viola

The purpose of this study was to observe the ultrastructure of human umbilical cord mesenchymal stem cells (hUCMSC). hUCMSC from full-term newborn umbilical cord were isolated and cultured by collagenase digestion, and then subcultured, amplification, and cell morphology was observed by microscopy. The immunophenotype and trilineage differentiation potential of hUCMSCs at passage 3 were analyzed. Transmission electron microscopy and scanning electron microscopy were used to observe the ultrastructure of hUCMSC. The results indicated that appearance of hUCMSC was spindle-shaped and polygonal, and nuclei were observed. hUCMSC expressed immunophenotype CD44, CD73, CD105, did not express CD34, CD45, CD31 and human leukocyte antigen HLA-DR. hUCMSC were capable of adipogenic, osteogenic, and cartilage differentiation; the short and thick microvilli processes were seen at the surface of hUCMSC by scanning electron microscope. Two different cell morphologies of hUCMSC were seen under transmission electron microscope, the one was a quiescent period in which a large and round or oval nucleus only one nucleolus were seen, cytoplasmic organelles were less; the other was in a relatively active period in which one or two nuclei in the same one cell were observed, the organelles were rich, structure was clear, expansion of the mitochondria was visible. It is concluded that the cells successfully isolated and cultured from umbilical cord, which possess biological characteristics of MSC and display two different states of ultrastructure.
Cells, Cultured ; Humans ; Mesenchymal Stromal Cells ; cytology ; ultrastructure ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Umbilical Cord ; cytology

BACKGROUNDTrichophyton rubrum (T. rubrum) is the most common causative agent of dermatophytosis worldwide. In this study, we examined the effect of laser irradiation on the growth and morphology of T. rubrum.

METHODSColonies of T. rubrum were isolated (one colony per plate), and randomly assigned to 5 treatment groups: Q-switched 694 nm ruby laser treatment, long-pulsed Nd:YAG 1064 nm laser treatment, intense pulsed light (IPL) treatment, 308 nm excimer laser treatment and the blank control group without treatment. Standardized photographs were obtained from grown-up fungal plates prior to treatment. Colonies were then exposed to various wavelengths and fluences of laser light. To compare the growth of colonies, they were re-photographed under identical conditions three and six days post-treatment. To investigate the morphology of T. rubrum, scanning electron microscope (SEM) and transmission electron microscope (TEM) images were obtained from specimens exposed to 24 hours of laser treatment.

RESULTSGrowth of T. rubrum colonies was significantly inhibited following irradiation by 694 nm Q-switched and 1064 nm long-pulsed Nd:YAG lasers. Other treatments exerted little or no effect. Q-switched laser irradiation exerted a stronger growth inhibitory effect than long-pulsed Nd:YAG laser irradiation. Following treatment by the Q-switched ruby laser system, T. rubrum hyphae became shrunken and deflated, and SEM images revealed rough, fractured hyphal surfaces, punctured with small destructive holes. TEM images showed that the hyphae were degenerating, as evidenced by the irregular shape of hyphae, rough and loose cell wall, and obscure cytoplasmic texture. Initially high electron density structure was visible in the cell; later, low-density structure appeared as a result of cytoplasmic dissolution. In contrast, the blank control group showed no obvious changes in morphology.

CONCLUSIONThe Q-switched 694 nm ruby laser treatment significantly inhibits the growth and changes the morphology of T. rubrum.

OBJECTIVE: To observe the biological characteristics of the human olfactory mucosa mesenchymal stem cells (hOM-MSCs). METHODS: The hOM-MSCs were isolated, cultured and identified in vitro. Scanning electron microscope and transmission electron microscope were used to observe the ultrastructure of hOMMSCs. Th e cells were induced towards adipocyte, osteocyte, neural stem cells, neural-like-cells in vitro. RESULTS: The hOM-MSCs were mainly in spindle shape, arranged with radial colony. The hOMMSCs expressed CD73 and CD90 but no CD34 and CD45. Th e short and thick microvilli processes were seen at the surface of hOM-MSCs by scanning electron microscope, and 2 different cellular morphology of hOM-MSCs were seen under transmission electron microscope. Moreover, the hOMMSCs could be differentiated into adipocyte, osteocyte, neural stem cells and neural cells. CONCLUSION The hOM-MSCs possess general biological characteristics of MSCs and display multiple differentiation functions. They can be served as ideal seed cells in tissue-engineering for injury repair.
Cell Differentiation ; Cells, Cultured ; Humans ; Mesenchymal Stem Cells ; cytology ; ultrastructure ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Olfactory Mucosa ; cytology