• The Korean Journal of Malacology
• /
• v.27 no.3
• /
• pp.273-282
• /
• 2011

The ultrastructural characteristics of germ cells during spermatogenesis and mature sperm morphology in male Pinctada martensii were investigated by transmission electron microscope observation. The morphologies of the sperm nucleus and the acrosome of this species are the oval shape and cone shape, respectively. Spermatozoa are approximately $47-50{\mu}m$ in length including a sperm nucleus (about $1.24{\mu}m$ in length), an acrosome (about $0.60{\mu}m$ in length), and tail flagellum (about $45-47{\mu}m$). The axoneme of the sperm tail shows a 9+2 structure. In P. martensii in Pteriidae, a special substructure showing a thick and wide triangular shape which is composed of electron-dense opaque material (occupied about 50% of all, the upper part of the acrosomal vesicle), appeared in the upper region (part) of the acrosomal vesicle, while the lower region (part) of the acrosomal vesicle is composed of electron-lucent material. Thus, this special structure, which exist in the upper part of the acrosomal vesicle in P. martensii, is somewhat different from those of other subacrosomal vesicle in other families in subacrosomal vesicles. Therefore, we assume that the existence of a special substructure showing a thick and wide triangular shape in the acrosomal vesicle of the spermatozoon can be used as a key characteristic for identification of P. martensii or other species in Pteriidae in subclass Pteriomorphia. The number of mitochondria in the midpiece of the sperm of this species are five (exceptionally sometimes four), as one of common characteristics appear the same number of mitochondria in the same families of superfamilyies. This species in Pteriidae does not contain the axial rod and satellite fibres which appear in the species in Ostreidae in subclass Pteriomorphia. These characteristics can be used for the taxonomic analysis of the family or superfamily levels as a systematic key or tools.

• Korean Journal of Pharmacognosy
• /
• v.11 no.2
• /
• pp.95-103
• /
• 1980

In our country there are five species of Morus genus including Morus alba L.. Also their varieties and hybrids are distributed so much. In sucession of previous report we collected control and marketing specimens of Mori Cortex Radicis, comparative experiments were pharmacognostically carried out to identify the control specimen by the differences of external and internal morphology. It was difficult to identify marketing specimens by external morphology, because they are similar in spite of conparating with control specimen which the origin is definite. In internal morphology, medullary ray is developed near the cambium to primary bark in control specimen A(Morus alba series) and C(M. Lhou series), but less developed in B(M. bombycis series). The difference of these three series was observed. The thickness of cork layer is almost the same($7{\sim}12$ layers) in A and C series, but B is thin layer and sample E(that on the market) is generally more thick and has a stick cork cell. The kinds of starch, Ca-oxalate and latex, cell centents were same, but it was easy to identify them by the differences of their distribution. The bast fibre of D(wild specimen) and E were light lignified, latex tube of A and C series was richer distributed than others. These results show that the origin of Mori Cortex Radicis on the market can be appreciated in four groups of Korean Morus genus which are M. alba, M. bambycis, M. Lhou series and the others.

• Polymer(Korea)
• /
• v.26 no.6
• /
• pp.759-766
• /
• 2002

Regular, spherical and isotropic open-microcellular foams having low density were prepared by the high internal phase emulsion (HIPE) polymerization mainly composed of styrene monomer and water The effects of Polymerization conditions. such as the content of water, divinylbenzene as a crosslinking agent and dodecane as a chain transfer agent, were investigated based on the tell size and foam properties. The microstructural morphology was observed using scanning electron microscopy (SEM) and the compression modulus of the foam was evaluated using compression test. The dropwise feeding of the aqueous phase into the oil phase was more effective than the batch feeding in producing the uniform and stable foam. Agitation speed and surfactant strongly influenced on the cell size and the window size between water droplets. Introduction of chain transfer agent increased the cell size, whereas it decreased the window size. Compression modulus increased with the crosslinking agent, but decreased with the chain transfer agent.

• Polymer(Korea)
• /
• v.39 no.2
• /
• pp.293-299
• /
• 2015

Conductive microcellular foams consisted of polystrene (PS) and polydopamine-coated carbon nanotube (PDA-CNT) were prepared via high internal phase emulsion (HIPE) polymerization and their morphology and electrical conductivity were investigated. CNT as a conductive nanofiller was modified to PDA-CNT by coating with hydrophilic PDA on the surface of CNT to increase aqueous phase dispersion and emulsion stability. It was possible to prepare the HIPEs having higher PDA-CNT content and the resultant foams having improved conductivity due to its good dispersion. The foams showed the morphology of interconnected cell structure. As PDA-CNT content increased, yield stress and storage modulus increased and cell size reduced. The PDA-CNT content showing electrical percolation threshold was ca. 0.58 wt% and the conductivity at PDA-CNT content of 5 wt% was increased to $10^{-3}S/m$.

• Journal of Veterinary Science
• /
• v.25 no.2
• /
• pp.31.1-31.8
• /
• 2024

Background: Recently, there has been a growing interest in stem cells for human medicine. Limited feline endometrial mesenchymal stem cell (fEM-MSC) research in veterinary medicine necessitates reporting for future feline disease research and therapy. Objectives: This study aimed to isolate fEM-MSCs from feline endometrial tissues and evaluate their morphology, proliferative ability, differentiation ability, and immunophenotype. Methods: Feline endometrial tissues were obtained from the ovariohysterectomies of healthy cats and isolated using an enzymatic method. The morphology and proliferative ability of the isolated cells were assessed using a doubling time (DT) assay from passages 3 to 6 (P3 - P6). We measured pluripotency gene expressions of cells in P2 using quantitative real-time polymerase chain reaction (qRT-PCR). To investigate MSC characteristics, a trilineage differentiation assay was conducted in P4, and cells in P4 were immunophenotyped using flow cytometry. Results: fEM-MSCs showed a typical spindle-shaped morphology under a microscope, and the DT was maintained from P3 to P6. fEM-MSCs could differentiate into adipocytes, osteoblasts, and chondrocytes, and expressed three pluripotency markers (OCT4, SOX2, and NANOG) by qRT-PCR. Immunophenotypic analysis showed that the fEM-MSCs were CD14 ^-, CD34 ^-, CD45 ^-, CD9⁺, and CD44⁺. Conclusions: In this study, the feline endometrium was a novel source of MSCs, and to the best of our knowledge, this is the first report on the isolation method and characteristics of fEM-MSCs.

• Current Photovoltaic Research
• /
• v.10 no.2
• /
• pp.39-48
• /
• 2022

A Se-containing Cu/SnSe₂/ZnSe precursor was employed to introduce S to the precursor to form Cu₂ZnSn(S,Se)₄ (CZTSSe) film. The morphology of CZTSSe films strongly varied with two different pre-annealing environments: S and N₂. The CZTSSe film with S pre-annealing showed a dense morphology with a smooth surface, while that with N₂ pre-annealing showed a porous film with a plate-shaped grains on the surface. CuS and Cu₂Sn(S,Se)₃ phases formed during the S pre-annealing stage, while SnSe and Cu₂SnSe₃ phases formed during the N₂ pre-annealing stage. The SnSe phase formed during N₂ pre-annealing generated SnS₂ phase that had plate shape and severely aggravated the morphology of CZTSSe film. The power conversion efficiency of the CZTSSe solar cell with S pre-annealing was low (1.9%) due to existence of Zn(S.Se) layer between CZTSSe and Mo substrate. The results indicated that S pre-annealing of the precursor was a promising method to achieve a good morphology for large area application.

• Anatomy and Cell Biology
• /
• v.57 no.2
• /
• pp.213-220
• /
• 2024

The jugular foramen (JF) is located between the temporal and occipital bones. The JF is a primary pathway for venous outflow from the skull and passage of nerves. Variations are common in this region and may have clinical and surgical implications. To analyze the sexual dimorphism and JF morphology in skulls from Northeastern Brazil. 128 human skulls from the Anatomy Laboratory of the Federal University of Paraíba, 64 male and 64 female, were selected and the JFs analyzed for bone septation and the presence of a dome. Data analysis considered P<0.05 as significant. On at least one side, complete septation was observed in 26 skulls (20.3%), incomplete septation in 93 skulls (72.6%) and 61 skulls (47.6%) did not present septation. In 114 skulls (89%), 47.6% female and 41.4% male, have a unilateral presence of the dome and 71 (55.4%) have it bilaterally. Posterolateral compartment diameters and JF area had higher values on the right side in the total sample and separated by sex (P<0.05). Most morphometric variables of the anteromedial compartment were higher in male than in female (P<0.05), fact that was not observed in the posterolateral compartment (P>0.05). This study showed a higher prevalence of complete septation in males compared to females. Morphometric analysis presented a peculiar morphology of the JF in this study. These results suggests that the surgical approach to diseases that affect the JF may be peculiar to the studied population, confirming the importance of morphological analysis of the skull base.

• International Journal of Oral Biology
• /
• v.32 no.1
• /
• pp.13-22
• /
• 2007

The stem cell research is emerging as a cutting edge topic for a new treatment for many chronic diseases. Recently, dental stem cell would be possible for regeneration of tooth itself as well as periodontal tissue. However, the study of the cell characterization is scarce. Therefore, we performed the genetic profiling and the characterization of mouse fetus/neonate derived dental tissue and cell to find the identification during dental development. We separated dental arch from mandibles of 14.5 d fetal mice and neonate 0 d under the stereoscope, and isolated dental cells primarily from the tissues. Then, we examined morphology and the gene expression profiles of the primary cells and dental tissues from fetus/neonate and adult with RT-PCR. Primary dental cells showed heterogeneous but the majority was shown as fibroblast-like morphology. The change of population doubling time levels (PDLs) showed that the primary dental cells have growth potential and could be expanded under our culture conditions without reduction of growth rate. Immunocytochemical and flow cytometric analyses were performed to characterize the primary dental cell populations from both of fetus (E14.5) and neonate. Alpha smooth muscle actin (${\alpha}-SMA$), vimentin, and von Willebrand factor showed strong expression, but desmin positive cells were not detected in the primary dental cells. Most of the markers were not uniformly expressed, but found in subsets of cells, indicating that the primary dental cell population is heterogeneous, and characteristics of the populations were changed during culture period. And mesenchymal stem cell markers were highly expressed. Gene expression profile showed Wnt family and its related signaling molecules, growth factors, transcription factors and tooth specific molecules were expressed both fetal and neonatal tissue. The tooth specific genes (enamelin, amelogenin, and DSPP) only expressed in neonate and adult stage. These expression patterns appeared same as primary fetal and neonatal cells. In this study we isolated primary cells from whole mandible of fetal and neonatal mice. And we investigated the characteristics of the primary cells and the profile of gene expressions, which are involved in epithelial-mesenchymal interactions during tooth development. Taken together, the primary dental cells in early passages or fetal and neonatal mandibles could be useful stem cell resources.

• Journal of Periodontal and Implant Science
• /
• v.31 no.1
• /
• pp.21-41
• /
• 2001

The goal of Periodontal treatment is predictable periodontal regeneration. But until now, many products including GTR materials and growth factors are beyond of complete regeneration. BMP can induce ectopic bone formation when implanted into sites such as rat muscle and can greatly enhance healing of bony defects when applied exogenously. BMP can promote periodontal regeneration by their ability to stimulate new bone and new cementum formation. But little is known about optimal conditions required for the application. Root conditioning is used for bioacive root change so altered root surface provides a substrate that promotes chemotaxis, migration and attachment of peridontal cells encouraging connective attachment to the denuded root surface. The aim of this study is to investigate whether the acid conditioning change effect of rhBMP-2 on human periodontal ligament cell and osteoblast cell line. 288 periodontally involved root dentin slices are divided into 6 groups, each 48, 1)control, 2)treated with BMP, 3)treated with citric acid 4)treated with citric acid+BMP 5)treated with tetracycline 6)treated with TC+BMP. Each group was devided half, so 12 root dentin slices were seeded with periodontal ligament cells and 12 were seeded with osteoblasts. At day 2 and 7, cell number, protein assay, ALP activitiy was measured. To investigate morphology of cultured cells, SEM was employed. Statistical analysis was performed with SPSS 8.0 either t-test or ANOVA test. The results are ; Protein assay and cell number was slightly decreased in CA+BMP group compared to Ca group but it was not statistically significant and ALP activity was much more increased in CA+BMP group compared to CA group so there was no statistically significance between BMP and CA+BMP group and statistically significant compared to control group. Cell number and protein assay was slightly increased in TC group and ALP activity was much less the BMP group and CA group. Cell number and protein and ALP activity was not much increased in TC+BMP group. TC group and TC+BMP group showed cell morphology change in SEM. This results suggested that application of root surface with citric acid before BMP treatment might give better result in periodontal regeneration.

• Tuberculosis and Respiratory Diseases
• /
• v.53 no.1
• /
• pp.52-55
• /
• 2002

A extrapulmonary small cell carcinoma is a very rare disease, and a primary pleural manifestation is extremely rare. A diagnosis of a small cell carcinoma should be based on the cell morphology, histological pattern, and an immunohistochemical study. We recently experienced a case of small cell carcinoma (SCC) of the pleura in a 59-year-old man who had suffered from right pleuritic chest pain. A histopathological confirmation of SCC was made by a video-associated thoracoscopic lung biopsy. Systemic chemotherapy with etoposide and cisplatin was initiated.