Transcriptional differential analysis of ocular surface ectoderm and surface ectoderm / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To identify transcriptional differences between the ocular surface ectoderm(OSE)and surface ectoderm(SE)using RNA-seq, and elucidate the OSE transcriptome landscape and the regulatory networks involved in its development.METHODS:OSE and SE cells were differentiated from human embryonic stem(hES)cells. Differentially expressed genes(DEGs)between OSE and SE were analyzed using RNA-seq. Based on the DEGs, we performed gene ontology(GO)analysis, Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis, and protein-protein interaction(PPI)network analysis. Transcription factors(TFs)and hub genes were screened. Subsequently, TF-gene and TF-miRNA regulatory networks were constructed using the NetworkAnalyst platform.RESULTS:A total of 4 182 DEGs were detected between OSE and SE cells, with 2 771 up-regulated and 1 411 down-regulated genes in OSE cells. GO-BP analysis revealed that up-regulated genes in OSE were enriched in the regulation of ion transmembrane transport, axon development, and modulation of chemical synaptic transmission. Down-regulated genes were primarily involved in nuclear division, chromosome segregation, and regulation of cell cycle phase transition. KEGG analysis indicated that up-regulated genes in OSE cells were enriched in signaling pathways such as cocaine addiction, axon guidance, and amphetamine addiction, while down-regulated genes were enriched in proteoglycans in cancer, ECM-receptor interaction, protein digestion and absorption, and cytokine-cytokine receptor interaction. Additionally, compared with SE, 204 TFs(including FOS, EGR1, POU5F1, SOX2, and PAX6)were up-regulated, and 80 TFs(including HAND2, HOXB6, HOXB5, HOXA5, and HOXB8)were down-regulated in OSE cells. Furthermore, we identified 6 up-regulated and 9 down-regulated hub genes in OSE cells, and constructed TF-gene and TF-miRNA regulatory networks based on these hub genes.CONCLUSIONS:The transcriptome characteristics of OSE and SE cells were elucidated through RNA-seq analysis. These findings may provide a novel insight for studies on the development and in vitro directed induction of OSE and corneal epithelial cells.

Epidermoid cyst in the right mandible: a case report and literature review / 口腔疾病防治

Objective@#To discuss the possible etiology, pathogenesis, clinical features, diagnosis and treatment of epidermoid cysts of the jaw and to provide a reference for clinical diagnosis and treatment.@*Methods@#A case of an epidermoid cyst in the right mandible with retained deciduous teeth and succedaneous impacted teeth was reviewed and analyzed in combination with the relevant literature.@*Results@#A patient presented with a mass in the right mandible that had persisted for 1 month after being found at imaging examination. Tooth 83 was retained, and tooth 43 was unerupted. Swelling was characterized by no obvious tenderness, fluctuation, or table tennis sensation and was observed in the lingual alveoli of teeth 83, 44, and 45. Imaging revealed a low-density shadow in the apex of teeth 83, 44, 45, and 46, approximately 1.9 cm × 2.6 cm × 1.6 cm in size, which wrapped around the dental crown of tooth 43. Preliminary diagnoses were as follows: right mandibular mass thought to be a dentigerous cyst; impacted tooth 43; and retained primary tooth 83. The mass in the right mandible was removed, and teeth 43 and 83 were extracted under intravenous and inhalation anesthesia. During the operation, the mass was observed to have a thin cyst wall and contained bean-like residue. Histopathological examination indicated an epidermoid cyst in the right mandible. At the 1-week follow-up examination, the patient reported no discomfort, and the surgical area showed good recovery. According to the literature, epidermoid cysts are benign cysts originating from ectopic ectodermal tissue that can occur throughout the body but rarely in the oral cavity and are even extremely rarer in the jaw. Epidermoid cysts of the jaw, which have no specific clinical manifestations, can be confused with odontogenic cysts such as dentigerous cysts and odontogenic tumors. Dental pulp tests and other techniques can serve as a reference for clinicians. The diagnosis is confirmed via histopathology. Surgical removal is a common treatment, with a good prognosis and a low recurrence rate.@*Conclusion@#The principle of treatment for an epidermoid cyst of the jaw is similar to that for a jaw cyst. The prognosis is good when the cyst is removed completely.

Uso del lexema δερµα (derma) en terminologia embryologica / Use of the lexeme δερµα (derm) in terminologia embryologica

Al lexema δερµα (derma) que proviene de las raíces griegas δέρ-µα/µατος se lo define como piel, pellejo, cuero, odre (Cortez, 2011). Lo encontramos en los términos ectodermo, mesodermo y endodermo, utilizados para describir las estructuras durante la tercera semana del desarrollo embriológico humano. Se consultó el significado y sus raíces en el diccionario Manuel Griego clásico-Español Vox (Pabón, 1967) y Diccionario Médico-Biológico, Histórico y Etimológico (DICCIOMED) de la Universidad de Salamanca (Cortez); de igual manera se investigó la utilización de los términos ectodermo, mesodermo y endodermo en la Terminologia Embryologica (FIPAT, 2013) y en su última versión (FIPAT, 2017). La búsqueda reportó que estos términos están compuestos por dos raíces griegas el sufijo δέρµα (derma) presente en los tres términos; más los prefijos ἐκτός que significa externo; µÎ­σος definido como medio y ἐνδο cuyo significado es dentro. Estos tres tejidos se derivan a la vez del epiblasto que viene de dos raíces griegas ἐπί- ep(í) que significa sobre + ßλαστός - blast(o) que se traduce como germen, retoño, forma celular inmadura; y del hipoblasto que cuyo término se forma de las raíces griegas ὑπό (hypó) que significa 'debajo de' + ßλαστός - blast(o). Podemos señalar que el mejor término para denominar a estas tres estructuras debiera ser ßλαστός (blasto); y por lo tanto, se deberían denominar a estas tres estructuras como ectoblasto, mesoblasto y endoblasto; debido a que son células o tejidos inmaduros, transitorios y no tejidos definitivos como es la piel; lo cual a su vez se corresponde con los objetivos determinados por la FIPAT.

The lexeme δέρ-µα (derma) that comes from the Greek δέρ-µα/µατος is defined as skin, hide, leather, wineskin (Cortez, 2011). We find it in the term ectoderm, mesoderm and endoderm, used to describe the structures during the third week of human embryological development. The meaning and its roots were consulted in the Manuel Greek-Spanish Vox dictionary (Pabón, 1967) and Medical-Biological, Historical and Etymological Dictionary (DICCIOMED) of the University of Salamanca (Cortez); the same way, the use of the terms ectoderm, mesoderm and endoderm was investigated in Terminologia Embryologica (FIPAT, 2013) and in its latest version Terminologia Embryologica (FIPAT, 2017). The search reported that these terms are composed of two Greek roots, the suffix δέρµα (derma) present in the three terms; plus the prefixes ἐκτός which means external; µÎ­σος defined as medium and ἐνδο whose meaning is within. These three tissues are derived in turn from the epiblast that comes from two Greek roots ἐπί- ep (í) which means over + ßλαστός - blast (o) which translates as germ, shoot, immature cell form; and from the hypoblast whose term is formed from the Greek roots ὑπό (hypó) meaning 'under' + ßλαστός - blast (o). We can say that the best term to name these three structures should be ßλαστός (blast); and therefore, these three structures should be named as ectoblast, mesoblast and endoblast; because they are immature, transitory cells or tissues and definitive non-tissues such as the skin; which in turn corresponds to the objectives determined by FIPAT.

Signaling pathways inducing embryonic stem cells to differentiate into epidermal and corneal epithelial cells / 中国药理学与毒理学杂志

Stem cells are a group of self-renewal cells with the potential to differentiate into a variety of cell lineages. Embryonic stem cells can differentiate into more than 200 types of cell lineages belonging to endodermal, mesodermal and ectodermal tissues. Corneal epithelial cells derive from epidermal ectoderm during embryonic development. When the ocular surface is severely damaged, corneal epithelium with proliferation potential is essential for its reconstruction. Recent studies are focused on differentiation of bioactive corneal epithelial cells. This review summarizes signaling pathways including Notch, Wnt, bone morphogenetc protein or fibroblast growth factor pathways that are involved in regu?lating the development of embryonic ectoderm and corneal epithelial cells revealed in previous studies.

The origin of endoderm: Transmission electron microscopic point of view.

Objective: To show the transmission electron microscopic (TEM) evidence to confirm that the endoderm originates from the epiblast of the primitive streak or from other sources. Methods: 60 fertilized Leghorn hen’s eggs were used in this study by incubating the eggs for about 18-27 hours at 38oC, then the chick embryos of the primitive streak stage to 7-somite stage were further processed for routine TEM study at the region of the primitive streak. Results: The epiblast proliferates and accumulates to form the primitive streak at the midcaudal of the embryonic disc from 18-27 hours incubation which corresponds with the early third week of the human embryo. TEM evidence shows that the epiblast at the primitive streak is the stratified columnar type of epithelium while the hypoblast is the simple squamous and the mesoderm cells are irregular in shape. The process of gastrulation begins with the formation of the filopodia of the epiblast by numerous protrusions of the plasma membrane from lateral side of the cell. These structures initiate the separation of the contacted cells. The deepest epiblast cells separate first while the superficial epiblast cells exhibit the desmosome between the adjacent cells. The separated epiblast cells are bottle-shaped with numerous filopodia and gradually change the shape into round or oval cells which migrate in the space between the epiblast and hypoblast. Some of these migrate to the hypoblast and contact with the hypoblast, the mesoblasts lose the filopodia and gain more close contact to the hypoblasts which become a very thin sheet of cells. The facing cell membrane later gradually disappears and the mesoblast then occupies the region of pre-existing hypoblast. There is no evidence that the mesoblast displaces the pre-existing hypoblast laterally to form the extraembryonic endoderm. Conclusion: These are TEM evidences that the epiblast of the primitive streak separates and migrates to form the mesoblast and some contact with the hypoblast. The later process appeared to reveal that the mesoblast compresses the hypoblast until the facing plasma membrane disappears and occupies the region of the pre-existing hypoblast.

A Case of Median Raphe Cyst on the Scrotum with Atypical Histologic Features / 대한피부과학회지

Median raphe cyst is an uncommon condition occuring on the ventral median raphe from the glans penis to the anus and represents a defect in the embryologic development of the male genitalia. The cyst wall may derive from endoderm, ectoderm, or mucous glands which are a normal constitute of the male urethra. It is classified as either a dermoid cyst lined by stratified squamous epithelium of ectodermal origin or a mucous cyst lined by cuboidal or columnar epithelium of endodermal origin. Surgical excision is the treatment of choice. We report a case of an 11-year old boy with three median raphe cysts of the scrotum. The epithelial lining of the cysts was mainly composed of pseudostratified columnar cells with decapitation secretion and focally showed stratified squamous cells and a transitional zone of two types of cells. Immunohistochemically, pseudostratified columnar cells showed CK 7 and CK 13 positivity, but were negative for CK 20. Besides, stratified squamous cells were negative for CK 7, CK 13 and CK 20. We report a rare case of median raphe cyst that is a combined type of dermoid cyst and mucous cyst.