• Applied Microscopy
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• v.29 no.2
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• pp.201-209
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• 1999

Remodeling of epithelial cells during wound healing in the skin of the Korean fire-bellied toad, Bombina orientalis, were examined using the scanning and transmission electron microscopical analyses. Artificial wounds were induced on the dorsal surface of the skin by excision, and reared in special cages with normal diets for up to 31 days after injury. From 4 days after wounding, regenerated epithelial cells are more rapidly migrated to wounding area, and remodeling of tissue components are proceeded gradually. Especially, formation of basal lamina between regenerated epithelium and dermis, and reconstruction of cellular junctions such as desmosomes (among the regenerated epithelial cells) and hemidesmosomes (between basal epithelial cells and basal lamina) are detected through fine structural analysis from 10 days after injury. Parakeratosis of regenerated epithelial cells observed during 16 to 19 days after wounding.

• Parasites, Hosts and Diseases
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• v.49 no.3
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• pp.285-290
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• 2011

Naegleria fowleri, a ubiquitous free-living ameba, causes fatal primary amebic meningoencephalitis in humans. N. fowleri trophozoites are known to induce cytopathic changes upon contact with microglial cells, including necrotic and apoptotic cell death and pro-inflammatory cytokine release. In this study, we treated rat microglial cells with amebic lysate to probe contact-independent mechanisms for cytotoxicity, determining through a combination of light microscopy and scanning and transmission electron microscopy whether N. fowleri lysate could effect on both necrosis and apoptosis on microglia in a time- as well as dose-dependent fashion. A $^{51}Cr$ release assay demonstrated pronounced lysate induction of cytotoxicity (71.5%) toward microglial cells by 24 hr after its addition to cultures. In an assay of pro-inflammatory cytokine release, microglial cells treated with N. fowleri lysate produced TNF-${\alpha}$, IL-6, and IL-$1{\beta}$, though generation of the former 2 cytokines was reduced with time, and that of the last increased throughout the experimental period. In summary, N. fowleri lysate exerted strong cytopathic effects on microglial cells, and elicited pro-inflammatory cytokine release as a primary immune response.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.26 no.1
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• pp.19-34
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• 2013

Objective : This study was performed to evaluate the effect of immune reaction inductive substances such as PMA, LPS, DPE, DNCB and WP, the whitman pigra extracting substance at simultaneously on the translocation of $NF{\kappa}B$ towards to the nucleus and the mRNA expression patterns of various cytokine genes in THP-1 cells, monocytes of human. Methods : To analyze the cytokine genes expressions, the RT-PCR method was used, and measuring TNF-${\alpha}$ that had been secreted during cell culture by the ELISA method. The morphological changes were observed during THP-1 cell by a scanning electron microscope and the quantitative distribution of $NF{\kappa}B$ in the cell that was analyzed through immunocytochemistry and a confocal microscopy. Results : WP showed different influences onto the mRNA expression patterns of cytokine genes with PMA, LPS. DPE and DNCB according to the types of immune inductive substances in the THP-1 cells. Upon treating PMA and DPE on the THP-1 cells at the same time or either additionally treating WP thereon, the movement of $NF{\kappa}B$ increase towards the nucleus from cell cytoplasm was able to be observed. The expressions of IL-$1{\alpha}$ and IFN-${\gamma}$ induced by PMA and PMA+DNCB were suppressed by WP while the expression of TGF-${\beta}$ was promoted. Regarding the secretion pattern of TNF-${\alpha}$ according to the treatment of PMA, its secretion amount was incredibly increased by concurrent treatment of WP, however, in case of co-treatment of WP with PMA and DNCB, it was found that the secretion amount of TNF-${\alpha}$ decreased. Conclusions : In this study, the WP extracting substance was confirmed that it had an influence on expression patterns of cytokine genes according to the actions of a variety kinds of immune reaction inductive substances treated on the THP-1 cells. Especially, WP co-treatment with PMA and DNCB was suppressed the expression of inflammatory cytokines, such as IL-$1{\alpha}$, IFN-${\gamma}$ and TNF-${\alpha}$.

• Applied Microscopy
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• v.29 no.2
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• pp.189-193
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• 1999

The response of ameloblast to long term (3 weeks) exposure to fluoride was examined in continuously erupting mandibular incisors of pregnancy rats as compared to control rats receiving a similar diet (Teklad L-356) but no sodium fluoride in there drinking water. Rats were started on water containing 0 ppm, 100 ppm, 200 ppm, and 300 ppm NaF at the beginning of pregnancy. To examine on the ultrastructural changes of the ameloblast, electron microscopy was used. The results indicated that rat incisors expressed two major changes in normal amelogenesis that could be attributed to chronic fluoride treatment. The fluoride produces marked alteration in the fine structure of ameloblast from teeth of young rats, such as large confluent distensions of the endoplasmic reticulum and swelling of isolated mitochondria, in particular on the morphology of the rough-surfaced endoplasmic reticulum. A graded series of alterations to these organelles were produced, and the severity of the changes would seem to be dependent on dose and time. This experimental data suggested that exposure prolonged of animal to high level of fluoride appears to induce morphological changes in the normal appositional growth and initial mineralization of enamel created during amelogenesis.

• Radiation Oncology Journal
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• v.9 no.1
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• pp.117-122
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• 1991

Malignant small round cell tumor (SRCT) of the thoracopulmonary region appears to originate in the soft tissues of the chest wall or the peripheral lung. A differential diagnosis of poorly differentiated small round cell tumors which include Ewing's sarcoma of bone and soft tissue, embryonal rhabdomyosarcoma, Askin tumor, neuroblastoma, peripheral neuroectodermal tumor, small cell osteogenic sarcoma and Iymphoma are often difficult by light microscopy alone. In recent, by the extensive studies electron microscopic examination, histochemical study, immune-chemical study, cytogenetics and gene analysis, these tumors may be derived from the primitive and pluripotential cells, differentiating into mesenchymal, epithelial and neural features in variable proportions. Treatment for SRCT of thoracopulmonary region is not determined because of massive involvement of the lung, pleura or soft tissues of the chest wall resulted in a dismal outcome despite aggressive surgery, irradiation and chemotherapy.

• Restorative Dentistry and Endodontics
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• v.25 no.4
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• pp.606-618
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• 2000

Dental pulp infection is most commonly caused by extensive dental caries, and some bacterial species invade root canals; bacterial components and products are thought to be associated with the pathogenesis of periapical periodontitis. A principle driving force behind pulpal disease response appears to lie in the host immune system's to bacteria and their products. We examined the production of interleukin $1{\beta}$ (IL-$1{\beta}$) and tumor necrosis factor ${\alpha}$(TNF-${\alpha}$) from human peripheral mononuclear cells, lymphocytes and monocytes stimulated by heat-killed Acitnobacillus actinomycetemcomitans (ATCC 29523), Porphyromonas gingivalis (ATCC 33277) and Prevotella intermedia (ATCC 25611), and also by their sonicated bacterial extracts (SBE), respectively. The effects of three strains of heat-killed bacteria and their SBEs on the morphology of cultured blood cell lines HL-60 (KCLB 10240) and J774A.1 (KCLB 40067) were observed under the inverted microscope. Ultrastructural changes of J774A.1 exposed to heat-killed P. intermedia and its SBE were investigated using transmission electron microscopy. Production of IL-$1{\beta}$ was reduced in human peripheral mononuclear cells after stimulation by sonic bacterial extracts of A. actinomycetemcomitans, P. gingivalis, and P. intermedia. Heat-killed and sonic extract of P. gingivalis inhibited the production of TNF-${\alpha}$ in peripheral mononuclear cells. Production of TNF-${\alpha}$ was inhibited in peripheral monocytes after stimulation by sonic extracts of A. actinomycetemcomitans, P. gingivalis, and P. intermedia. HL-60 and J 774A.1 cells showed granular degeneration after treatment with heat-killed and sonic extracts of A. actinomycetemcomitans, P. gingivalis, and P. intermedia Chromatin margination and shrinkage were observed in 774A.1 treated with heat-killed P. intermedia. Cell wall structure and organelles were destroyed and vacuoles were formed in cytoplasm in J774A.1 treated with P. intermedia sonic extract. These results suggest that A actinomycetemcomitans, P gingivalis and P intermedia may have an important role in the formation and progression of pulpal diseases via both modulation of production of IL-$1{\beta}$ and TNF-${\alpha}$ from blood mononuclear cells and cytopathic effects.

• Parasites, Hosts and Diseases
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• v.58 no.2
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• pp.173-179
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• 2020

Leishmaniasis is a prevalent cause of death and animal morbidity in underdeveloped countries of endemic area. However, there is few vaccine and effective drugs. Antimicrobial peptides are involved in the innate immune response in many organisms and are being developed as novel drugs against parasitic infections. In the present study, we synthesized a 5-amino acid peptide REDLK, which mutated the C-terminus of Pseudomonas exotoxin, to identify its effect on the Leishmania tarentolae. Promastigotes were incubated with different concentration of REDLK peptide, and the viability of parasite was assessed using MTT and Trypan blue dye. Morphologic damage of Leishmania was analyzed by light and electron microscopy. Cellular apoptosis was observed using the annexin V-FITC/PI apoptosis detection kit, mitochondrial membrane potential assay kit and flow cytometry. Our results showed that Leishmania tarentolae was susceptible to REDLK in a dose-dependent manner, disrupt the surface membrane integrity and caused parasite apoptosis. In our study, we demonstrated the leishmanicidal activity of an antimicrobial peptide REDLK from Pseudomonas aeruginosa against Leishmania tarentolae in vitro and present a foundation for further research of anti-leishmanial drugs.

• Safety and Health at Work
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• v.13 no.1
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• pp.9-16
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• 2022

Background: The global shift toward greener societies demands new technologies and work operations in the waste-management sector. However, progressive industrial methods do not necessarily consider workers' health. This study characterized workers' exposure to bioaerosols and investigated the bioaerosols' potential to engage the immune system in vitro. Methods: Full shift personal aerosol sampling was conducted over three consecutive days. Dust load was analyzed by gravimetry, fungal and actinobacterial spores were analyzed by scanning electron microscopy, and endotoxin by limulus amebocyte lysate (LAL) assay. In vitro exposure of HEK cells to airborne dust samples was used to investigate the potential of inducing an inflammatory reaction. Results: The total dust exposure level exceeded the recommended occupational exposure limit (OEL) of 5.0 mg/m³ in 3 out of 15 samples. The inhalable endotoxin level exceeded the recommended exposure level by a 7-fold, whereas the fungal spore level exceeded the recommended exposure level by an 11-fold. Actinobacterial spores were identified in 8 out of 14 samples. In vitro experiments revealed significant TLR2 activation in 9 out of 14 samples vs. significant TLR4 activation in all samples. Conclusion: The present study showed that the dust samples contained potentially health-impairing endotoxin, fungi, and actinobacterial levels. Furthermore, the sampled dust contained microbial components capable of inducing TLR activation and thus have the potential to evoke an inflammatory response in exposed individuals.

• Applied Microscopy
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• v.30 no.1
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• pp.101-111
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• 2000

In this study, the distribution of lectin receptors in Paragonimus westermani tissue was explored using colloidal gold label complexed with lectin WGA purified from wheat germ (Triticum vulgare). The lectin WGA gold complex, shown to recognize GlcNAc (N-acetylgalactosamine) and NeuNAc (N-acetylneuraminic acid) regions, was applied to detect binding sites in Lowicryl HM 20 sections viewed under electron microscope. Labeled sections of the metacercaria revealed gold particles specifically distributed on the tegumental syncytium and lamella of the excretory canal. Labeling of young adult tissue was then quantified and compared to that of adult worm tissue. Adult worm tissue sections resulted in specific gold particle distribution on the lamella of caecal epithelium and excretory canal. These results indicate that lectin WGA receptors are located in the tegumental syncytium and lamella of the excretory canal of the metacercariae, and in the lamella of the caecum and excretory canal of the young adult and adult. Therefore, the GlcNAc and NeuNAc regions in the tegumental syncytium appear to be functionally associated with cell-recognition and protection from the immune system of the host, and linked with membrane transport and absorption of nutrients in the lamella of the excretaory canal and caecal epithelia.

• Applied Microscopy
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• v.39 no.2
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• pp.167-173
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• 2009

Capillaria hepatica is a parasitic nematode which causes hepatic capillariasis in rodents and other mammals, including man. Rat species of the genus Rattus are main primary host and rates of genus Rattus of up to 100% have been reported. Infection to reservoir and other mammalian hosts occur incidentally due to ingestion of water or food contaminated with C. hepatica embryonated eggs. The worms mature exclusively inside the liver, but they die and disassemble soon after egg spawning in rats. Dead worms and their eggs cause immune response of focal necrosis and inflammation within the liver. C. hepatica adult with a thin and long body is similar to capillary. The members of Order Trichurida are characterized by having a stichosome and the bacillary bands in front of the body. As already mentioned, the adult C. hepatica residesin the liver, where it deposits groups of eggs, and finally die in the encapsulated tissue of the liver. They produce eggs that elicit a marked granulomatous reaction that eventually destroy the worms. And the adult worms were mixed with eggs. So the complete isolation of the worm and observation of intact ultrastructure is very difficult. In this study, integument structure of C. hepatica isolated from the liver of mouse at 7 weeks after inoculation of embryonated eggs were observed with scanning and transmission electron microscopy. As a results, body length of isolated C. hepatica was about 99 mm. Cuticle, bacillary band and bacillary pore were obtained in the integument of worm. Bacillary pore across cuticular surface of the worm were observed. According to the existence of cap material, external forms of bacillary pore can be divided into three types such as flat, ingression, and ingression with the cap material type. The complete isolation of the worm and observation of ultrastructure of integument will provide the fundamental data which is important in the nematode research including C. hepatica.