Introduction: Dengue virus (DENV), the causative agent of dengue disease exists in sylvatic and endemic ecotypes. The cell morphological changes and viral morphogenesis of two dengue ecotypes were examined at the ultrastructural level to identify potential similarities and differences in the surrogate model of enzootic host. Materials and Methods: Vero cells were inoculated with virus at a multiplicity of infection (MOI) of 0.1. Cell cultures were harvested over a time course and processed for transmission electron microscopic imaging. Results: The filopodia protrusions on cell periphery preceded virus entry. Additionally, sylvatic DENV infection was found spreading slower than the endemic DENV. Morphogenesis of both dengue ecotypes was alike but at different level of efficiency in the permissive cells. Conclusions: This is the first ultrastructural study on sylvatic DENV and this comparative study revealed the similarities and differences of cellular responses and morphogenesis of two dengue ecotypes in vitro. The study revealed the weaker infectivity of sylvatic DENV in the surrogate model of enzootic host, which supposed to support better replication of enzootic DENV than endemic DENV.
; viral morphogenesis

During embryonic development, organs undergo distinct and programmed morphological changes as they develop into their functional forms. While genetics and biochemical signals are well recognized regulators of morphogenesis, mechanical forces and the physical properties of tissues are now emerging as integral parts of this process as well. These physical factors drive coordinated cell movements and reorganizations, shape and size changes, proliferation and differentiation, as well as gene expression changes, and ultimately sculpt any developing structure by guiding correct cellular architectures and compositions. In this review we focus on several craniofacial structures, including the tooth, the mandible, the palate, and the cranium. We discuss the spatiotemporal regulation of different mechanical cues at both the cellular and tissue scales during craniofacial development and examine how tissue mechanics control various aspects of cell biology and signaling to shape a developing craniofacial organ.
Cell Differentiation ; Morphogenesis ; Signal Transduction ; Skull ; Tooth

Coactosin-like protein 1 (Cotl1), a member of the actin-depolymerizing factor (ADF)/cofilin family, was first purified from a soluble fraction of Dictyostelium discoideum cells. Neuronal migration requires cytoskeletal remodeling and actin regulation. Although Cotl1 strongly binds to F-actin, the role of Cotl1 in neuronal migration remains undescribed. In this study, we revealed that Cotl1 overexpression impaired migration of both early- and late-born neurons during mouse corticogenesis. Moreover, Cotl1 overexpression delayed, rather than blocked, neuronal migration in late-born neurons. Cotl1 expression disturbed the morphology of migrating neurons, lengthening the leading processes. This study is the first to investigate the function of Cotl1, and the results indicate that Cotl1 is involved in the regulation of neuronal migration and morphogenesis.
Actins ; Animals ; Dictyostelium ; Humans ; Mice ; Morphogenesis ; Neurons

Radiographic research was performed to know the frequency of two-phalanged fifth toe and its relation to presence of the ossification centers in normal Korean children. Previous study showed more than 74% of the incidence in adulthood and less than 30% in childhood. Fifty children (33 male and 17 female, aged 2 to 15; mean age 9.6) were studied by plain foot radiographs focused on the fifth toe. In the 3~8 yr old 20 subjects, secondary ossification center of distal phalangeal bone was seen as a ossicle (small bone) placed at proximal to the distal phalanx. Secondary ossification center of middle phalangeal bone and the bony shaft of the phalanx was hard to distinguish. So keeping up the objectivity, regardless of distinguishable ossification center or the bony shaft of phalanges, ossicles seen on the 5th toe was counted to classify the presumptive type of the toe. Epiphyseal ossification center of proximal phalanx was excluded from the count. There were three types of the fifth toe which has 2 ossicles to 4 ossicles. Overall incidence of the type of 2 ossicles was 24% (12/50). Above 12 yr old group the incidence was 61% (11/18), and above 13 yr old group the incidence was 75% (9/12). The incidence of biphalangism came closer to the adult's after late childhood. This finding represent that progress of biphalangealization completed after late childhood. It seems that the progress starts earlier than 3 yr old. We made the hypothesis by the incidence of 30% (6/20) of the type which has 4 ossicles on the fifth toe at 3~8 yr old group. Four ossicles might be a secondary ossification center of distal phalanx and the bony shaft of distal, middle and proximal phalanx. They might form a distal interphalageal joint and the triphalangeal toe. To know more about the morphogenesis of biphalalngeal 5th toe, further progressive study in childhood is needed.
Child* ; Female ; Foot ; Humans ; Incidence ; Joints ; Male ; Morphogenesis ; Toes*

E-cadherin (ECD) is a Ca++ -dependent adhesion molecule which plays a major role in the maintenance of intercellular adhesion in epithelial tissues. The expression pattern of ECD in 77 surgically resected gastric adenocarcinomas was examined by immunohistochemistry, using a rat monoclonal antibody raised against murine E-cadherin (DECAM-1). ECD was strongly expressed uniformly at cell to cell borders in normal gastric epithelium without exception. But, various staining patterns were observed in the cancer tissues. The frequency of tumors with preserved ECD expression (Pre-type) and reduced ECD expression (Rd-type) was 44% and 56%, respectively. Using Lauren's classification, the high frequency of the Pre-type expression in adenocarcinoma of the intestinal type was significantly higher than that in adenocarcinoma of the diffuse type (p<0.05). But, no significant correlation between the ECD expression and the gross type, invasion depth, growth pattern or metastasis was observed. These results suggest that ECD might play a key role in the morphogenesis of gastric adenocarcinoma.
Adenocarcinoma* ; Animals ; Cadherins* ; Classification ; Epithelium ; Immunohistochemistry ; Morphogenesis ; Neoplasm Metastasis ; Rats

Mitochondria are essential for proper neuronal morphogenesis and functions, as they are the major source of energy for neural development. The dynamic morphology of mitochondria determines the key functions of mitochondria. Several regulatory proteins such as dynamin-related protein 1 (Drp1) are required to maintain mitochondrial morphology via a balance between continuous fusion and fission. Activity of Drp1, a key regulator in mitochondrial fission, is modulated by multiple post-translation modifications and receptor interactions. In addition, numerous researches have revealed that the regulation of Drp1 activity and mitochondrial dynamics is closely associated with several neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. In this article, we concisely review the recent findings about the biological importance of Drp1-mediated mitochondrial fission in neurons under physiological and pathological conditions.
Mitochondria ; Mitochondrial Dynamics ; Morphogenesis ; Nervous System ; Neurodegenerative Diseases ; Neurons ; Proteins

BACKGROUND: Calcipotriol(MC903), a new vitamin D(3) analogue, has been reported to be effective in the treatment of patients with psoriasis. OBJECTIVE: The purpose of this study is to examine the effects of calcipotriol on proliferation and differentiation of the keratinocytes in monolayer cultures and three-dimensional cultures. METHODS: Using moriolayer cultures, we examined morphological changes of keratinocytes and performed [(3)H]thymidine incorporation after calcipotriol was added into the medium. Using three dimensional cultures, we performed two experiments: one with cultures treated with calcipotriol immediately after the keratinocytes had been exposed to the air and another set of cultures treated with calcipotriol after three dimensional morphogenesis of the keratinocytes. We examined morphological changes of keraitinocytes and performed a immunohistochemical study for proliferation differentiation markers RESULTS: In monolayer cultures, at calcipotriol concentrations of 10(-9)M-10(-6)M, keratinocytes became larger, more irregular, and flattened in a dose-dependent manner. At 10(-9)M-10(-6)M, [3Hl thymidine incorporatiorn was decreased dose-dependently as compared to the control culture. In the first experiment using three-dimensional cultures, at 10(-9)M-10(-6)M, total epidermal layers were thinned. This was associated with thinnings of nucleated and horny layers in a dose dependent manner. In the seconcd experiment using three-dimensional cultures, at 10(-8)M-10(-6)M, nucleated layers were thinned in a dose dependent manner, but the horny layer was slightly thickened, as compared to the control culture. Immunohistochemical studies showed a reduction of differentiation markers such as keratin 1, involucrin, filaggrin, loricrin consistent with a thinning of nucleated layers in the epidermal architecture in both experiments. In the basal layer, at 10(-9)M-10(-6), PCNA-positive cells were and BrdU-positive cells were decreased dose-dependently as compared to the control culture. CONCLUSIONS: In this study, we demonstrated that at 10(-9)M-10(-6) calcipotriol inhibited keratinocytes proliferation and stimulated keratinocytes differentiation in a dose-dependent manner.
Antigens, Differentiation ; Humans* ; Keratin-1 ; Keratinocytes* ; Morphogenesis ; Psoriasis ; Thymidine ; Vitamins

Tooth root morphogenesis involves two biological processes, root elongation and dentinogenesis, which are guaranteed by downgrowth of Hertwig's epithelial root sheath (HERS) and normal odontoblast differentiation. Ubiquitin-dependent protein degradation has been reported to precisely regulate various physiological processes, while its role in tooth development is still elusive. Here we show ubiquitin-specific protease 34 (USP34) plays a pivotal role in root formation. Deletion of Usp34 in dental mesenchymal cells leads to short root anomaly, characterized by truncated roots and thin root dentin. The USP34-deficient dental pulp cells (DPCs) exhibit decreased odontogenic differentiation with downregulation of nuclear factor I/C (NFIC). Overexpression of NFIC partially restores the impaired odontogenic potential of DPCs. These findings indicate that USP34-dependent deubiquitination is critical for root morphogenesis by stabilizing NFIC.
Cell Differentiation ; Female ; Morphogenesis ; NFI Transcription Factors ; Odontogenesis ; Tooth Root

Among all types of cancer, incidence of lung cancer remains the highest with regard to cancer-related mortality. Problems contributing to recurrence of the disease include metastasis and drug resistance. Mounting evidence has demonstrated involvement of epithelial mesenchymal transition (EMT) in cancer progression. EMT is a critical mechanism ensuring tissue remodeling during morphogenesis of multicellular organisms. Therefore, understanding of the biology of this process for identification of potential EMT-targeted therapeutic strategies for the benefit cancer patients is necessary. This review describes recent evidence of EMT involvement in drug resistance and metastasis of cancers, with an emphasis on lung cancer.
Biology ; Drug Resistance ; Epithelial-Mesenchymal Transition ; Humans ; Incidence ; Lung ; Lung Neoplasms ; Morphogenesis ; Neoplasm Metastasis ; Recurrence

The effect of 1% Na-Hyaluronan(Na-HA) on the morphogenesis of microvilli in superficial epithelial cells and of hemidesmosomes in basal epithelial cells together with the organization of superficial stromal collagen were evaluated in n-heptanol induced corneal epithelial wounds. Epithelial wounds were produced by applying a 5.5mm round filter paper, soaked in n-heptanol, on the central cornea for 60 seconds. 1% Na-HA in phosphate buffered saline(PBS) or PBS alone were instilled 4 times a day for 3 days. Epithelial healing rates determined during the first two days were not altered by Na-HA. The number of microvilli in superficial epithelial cells and of collagens fibers in superficial stroma were approximately the same between two groups. However, the number of hemidesmosome in the central cornea, which was counted in 2micrometer length of the basement membrane, significantly increased by the treatment with 1% Na-HA, being 10.0+/-1.1 in the 1% Na-HA treated group and 6.5+/-2.5 in the control group. The results suggest that topically applied 1% Na-HA may enhance the formation of hemidesmosome in n-heptanol wounded cornea.
Basement Membrane ; Collagen ; Cornea ; Epithelial Cells* ; Hemidesmosomes ; Heptanol ; Microvilli ; Morphogenesis* ; Wounds and Injuries*