• Applied Microscopy
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• v.25 no.1
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• pp.48-64
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• 1995

Ultrastructure of nerves and their associated cells in the bronchiolar epithelium of the human fetal lung were studied with ultrastructural and immunohistochemical methods. The neuroendocrine cells were scattered along the basal part of non-ciliated respiratory epithelium and appeared as single cell (solitary neuroendocrine cell) or groups (neuroepithelial bodies). The solitary neuroendocrine cells were devoid of any detectable innervation, while the neuroepithelial bodies were associated with nerve ending containing morphologically afferent (sensory) and efferent (motor) intraepithelial terminals. The afferent nerve endings contained abundant mitochondria with long cristae. The efferent nerve endings were characterized by the presence of synaptic vesicles. Both types of nerve endings formed synaptic junction between nerve endings and neuroepithelial bodies cells. Serial sections of the intraepithelial nerves revealed that both morphologically afferent and efferent types of nerve endings may be formed by the same nerve fiber. By immunohistochemistry, bombesin and serotonin were localized in solitary neuroendocrine cells and neuroepithelial bodies of human fetal lung from various prenatal age groups. These results suggest that the neuroepithelial bodies cells of the human fetal lung have neuroreceptor function.

• Applied Microscopy
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• v.29 no.1
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• pp.105-124
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• 1999

Histological and ultrastructural differentiations of the neuroepithelial cells in the mouse embryo during neurulation were observed. The neural plates and grooves consisted of pseudostratified columnar epithelium in the embryonic day (ED) 8 embryo were developed. In the ED 9 embryo, the neural tube was developed in all body length of embryo except both the cephalic and caudal ends. Secondary neurulation was shown at the tail bud of the ED 10 embryo. In the ED 8 embryo, the primitive streak was shown in the posterior end of the embryonic disc. The neuroepithelium, notochord and mesenchyme were well differentiated in the cephalic and cervical portions. In the ED 9 and 10 embryos, the roof plates of neural tubes were constituted of the closing of the surface ectodermal cells in the hindbrain and the neuroepithelial cells in the spinal cord. The floor plate of neural tube were consisted of the low pseudostratified columnar epithelium. The spinal motor nerve fibers were initially differentiated in the ED 10 embryo. According to the electron density of the cell and the differentiation of tell organelles, the neuroepithelial cells in the ED 9 and 10 embryos were classified into three types: dark, intermediate and light types. All types in the ED 9 embryo were observed but the dark cell in the ED 10 embryo was not done. The free ribosomes and polysomes in all neuroepithelial cells were developed. The RER and lipid droplets in the dark cell and the Golgi complex in the intermediate and light cells were observed. Many microfilaments in the cytoplasmic processes of intermediate cell and the microfilaments and microtubules in the light cell processes were observed to be well differentiated.

• Journal of Korean Neurosurgical Society
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• v.61 no.3
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• pp.333-342
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• 2018

Intracranial germ cell tumors (iGCTs) are a heterogeneous group of tumors with peculiar characteristics clearly distinguished from other brain tumors of neuroepithelial origin. Diverse histology, similarity to gonadal GCT, predilection to one sex, and geographic difference in incidence all present enigmas and fascinating challenges. The treatment of iGCT has advanced for germinoma to date; thus, clinical attention has shifted from survival to long-term quality of life. However, for non-germinomatous GCT, current protocols provide only modest improvement and more innovative therapies are needed. Recently, next-generation sequencing studies have revealed the genomic landscape of iGCT. Novel mutations in the KIT-RAS-MAPK and AKT-MTOR pathways were identified. More importantly, methylation profiling revealed a new method to assess the pathogenesis of iGCT. Molecular research will unleash new knowledge on the origin of iGCT and solve the many mysteries that have lingered on this peculiar neoplasm for a long time.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.1
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• pp.9-17
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• 2001

It has been demonstrated that multipotent neuronal progenitor cells can be isolated from the developing or adult CNS and proliferated in vitro in response to epidermal growth factor. The present study was undertaken to investigate the differentiation of neuronal progenitor cells after transplantation into the neonatal rat forebrain striatum. Primary cultured progenitor cells were labeled with 3,3'-dioctadecycloxacarbonyl- amine perchlorate (DiO). DiO labeled progenitor cells were implanted into neonatal rat striatum. Implanted DiO labeled progenitor cells were differentiated into astrocytes and GABAergic neurons. These results suggest that implanted progenitor cells can be differentiated into neurons in host forebrain striatum. In addition, our data show that DiO labeling is a useful technique for tracing implanted progenitor cells.

• Journal of Chest Surgery
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• v.25 no.8
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• pp.806-811
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• 1992

The primary neuroendocrine carcinomas[NEC] of the lung are relatively rare. There are classified histologically into the following groups. 1] bronchial carcinoid, 2] well differentiated neuroendocrine carcinoma[WDNC], 3] intermediate cell neuroendocrine carci-noma[ICNC], 4] small cell neuroendocrie carcinoma[SCNC]. The NE cells can be found throughout the mucosa of the bronchial tree by the electron microscopy. By the immunocytochemistry, Neuron-specific enolase[NSE], serotonin, born-csin, and calcitonin are found in normal solitary NE cells and neuroepithelial bodies. The immunohistochemistry has the advantage that it can be applied on routine pathology specimens. The NSE was localized in all of the NE granule bearing tumors but also present in 57 per cent of the non NE carcinomas. Together the combination of chromogranin A, bombesin and NSE should provide an exellent signature for tumor cells expressing NE features, such as carcinoids and other NE carcinomas. We have experienced two cases of primary pulmonary NEC in 59 and 29 years old men. The former was admitted due to exertional dyspnea and left chest pain, the latter, newly developed mass on chest X-ray. They were treated by Lt pneumonectomy with LN dissection and RLL resection with LN dissection The postoperative diagnoses were could be confirmed by NSE study as NEC which were SCNEC and INEC in subgroups. The postoperative courses were uneventful.

• Molecules and Cells
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• v.37 no.1
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• pp.59-65
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• 2014

Eph receptors and their ligands ephrins have been implicated in guiding the directed migration of neural crest cells (NCCs). In this study, we found that Wnt1-Cre-mediated expression of ephrinA5-Fc along the dorsal midline of the dien- and mesencephalon resulted in severe craniofacial malformation of mouse embryo. Interestingly, expression of cephalic NCC markers decreased significantly in the frontonasal process and branchial arches 1 and 2, which are target areas for the migratory cephalic NCCs originating in the dien- and mesencephalon. In addition, these craniofacial tissues were much smaller in mutant embryos expressing ephrinA5-Fc. Importantly, EphA7-positive cephalic NCCs were absent along the dorsal dien- and mesencephalon of mutant embryos expressing ephrinA5-Fc, suggesting that the generation of cephalic NCCs is disrupted due to ephrinA5-Fc expression. NCC explant experiments suggested that ephrinA5-Fc perturbed survival of cephalic NCC precursors in the dorsal midline tissue rather than affecting their migratory capacity, which was consistent with our previous report that expression of ephrinA5-Fc in the dorsal midline is responsible for severe neuroepithelial cell apoptotic death. Taken together, our findings strongly suggest that expression of ephrinA5-Fc decreases a population of cephalic NCC precursors in the dorsal midline of the dien- and mesencephalon, thereby disrupting craniofacial development in the mouse embryos.

• Advances in pediatric surgery
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• v.1 no.2
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• pp.122-132
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• 1995

Teratoma contains elements derived from all three embryonic germ layers and mature teratomas are entirely composed of mature differentiated tissues, while immature types always contain additional embryonic tissues of variable degree of immaturity, especially neuroepithelial elements. Twenty cases of teratoma in infancy and childhood were reviewed and the clinical features and pathologic findings including PCNA expression were studied. Sacrococcygeal teratomas were the most common type(45%), followed by retroperitoneal and ovarian teratomas. There was a predilection of females in a ratio of 4:1 and age distribution was most prevalent below the first year of age(45%). But in ovarian teratomas, the age at diagnosis was above 4 years of age in all cases. Serum alpha-fetoprotein levels were checked in 18 cases. In all mature teratomas and 1 of 5 immature teratomas, the levels were normal. But in 4 of 5 immature teratomas, the serum levels were elevated and progressively declined to normal range after mass excision. Radiologically, calcifications in tumor were found in 60.0% of teratomas and was higher in mature teratomas(69.2%) than immature teratomas(42.9%). Immunohistochemical staining for PCNA(proliferating cell nuclear antigen) was done in 16 cases and PCNA expression was higher in grade III immature teratomas than grade I and II. The operative modes were complete mass excisions. Five immature teratomas were treated with multiagent PEB(Bleomycin, Etoposide, Cisplatin) adjuvant chemotherapy, 3 tolerated well without significant complications, but in one case, severe bone marrow suppression was developed and died of sepsis. In conclusion, grade III immature teratoma showed higher PCNA expression than mature or lower grade immature teratoma, which suggests that chemotherapy after surgical excision may be effective modality for grade III immature teratoma. We think, however, multicenter study is necessary because of low incidence of immature teratoma.