• Journal of the korean society of oceanography
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• v.37 no.2
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• pp.58-65
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• 2002

The study of microbial communities in sediments is impaired by the lack of reliable extraction methods. This study reports on the efficiency of recovery of a method for extracting bacteria, protists and diatoms from sandy sediments using a modified decant/fix method. The best extractions were achieved after fixation with a microtubule stabilising fixative and subsequent sonication for 80 seconds. We estimate that the efficiencies of recovery of bacteria and mixed heterotrophic flagellates were $96.4{\pm}3.5\%$ and $96.9{\pm}4.6\%$, respectively. Diatoms were recovered with an efficiency of 38-83% and varied considerably from species to species. This study suggests that the decant/fix method is effective in extracting small cells such as bacteria and heterotrophic flagellates, and that the efficiency of recovery of the method varies due to cell length and different types of organisms. When microbial carbon biomass had been underestimated by up to 32%, with much of that relating to larger cells such as microalgae and ciliates. We note that the corrected abundances may be still a subset of the total numbers present.

• The Journal of Korean Obstetrics and Gynecology
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• v.28 no.2
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• pp.1-14
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• 2015

Objectives : This study was designed to investigate the effects of Taraxaci Herba (TH) on cell death in breast cancer cells. Methods : In this experiment, the effects of TH on proliferation rates, cell morphology and growth pattern, intracellular reactive oxygen species (ROS) production. In addition, the effects on nuclear condensation, fragmentation and formation of acidic vesicular organelles (AVO) in MCF-7 cells were also investigated. Finally, autophagy related with protein was observed by using western blot method. Results : TH inhibited proliferation of MCF-7 cells, TH elevated intracellular ROS levels significantly. Treatment with TH did not affect nuclear morphologies such as condensation or fragmentation. On the other hand, TH treatment effectively induced AVO. Finally, one of autophagy related with protein, Microtubule-associated proteins 1A/1B light chain 3A (MAP1LC3A, LC3) level was elevated by treatment with TH. Conclusions : These data indicate that TH is able to be used for patient with breast cancer and mechanisms are involved in autophagy through ROS generation.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.384-389
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• 2014

Adiponectin, an adipokine predominantly secreted from adipose tissue, exhibits diverse biological responses, including metabolism of glucose and lipid, and apoptosis in cancer cells. Recently, adiponectin has been shown to modulate autophagy as well. While emerging evidence has demonstrated that autophagy plays a role in the modulation of proliferation and apoptosis of cancer cells, the role of autophagy in apoptosis of cancer cell caused by adiponectin has not been explored. In the present study, we demonstrated that globular adiponectin (gAcrp) induces both apoptosis and autophagy in human hepatoma cell line (HepG2 cells) and breast cancer cells (MCF-7), as evidenced by increase in caspase-3 activity, Bax, microtubule-associated protein light chain 3-II (LC3 II) protein levels, and autophagosome formation. Interestingly, gene silencing of LC3B, an autophagy marker, significantly enhanced gAcrp-induced apoptosis in both HepG2 and MCF-7 cell lines, whereas induction of autophagy by rapamycin, an mTOR inhibitor, significantly prevented gAcrp-induced apoptosis in hepatoma cells HepG2. Furthermore, modulation of autophagy produced similar effects on gAcrp-induced Bax expression in HepG2 cells. These results implicate that induction of autophagy plays a regulatory role in adiponectin-induced apoptosis of cancer cells, and thus inhibition of autophagy would be a novel promising target to enhance the efficiency of cancer cell apoptosis by adiponectin.

• Advances in concrete construction
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• v.9 no.5
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• pp.491-501
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• 2020

Microtubules buckle under bending and torsion and this property has been studied for free microtubules before using orthotropic elastic shell model. But as microtubules are embedded in other elastic filaments and it is experimentally showed that these elastic filaments affect the critical buckling moment and critical buckling torque of the microtubules. To prove that, we developed orthotropic Winkler like model and demonstrated that the critical buckling moment and critical buckling torque of the microtubules are orders of higher magnitude than those found for free microtubules. Our results show that Critical buckling moment is about 6.04 nNnm for which the corresponding curvature is about θ = 1.33 rad /㎛ for embedded MTs, and critical buckling torque is 0.9 nNnm for the angle of 1.33 rad/㎛. Our results well proved the experimental findings.

• ALGAE
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• v.31 no.2
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• pp.117-128
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• 2016

Cryptomonas curvata Ehrenberg is a photosynthetic freshwater flagellate and the type species of the genus Cryptomonas. We examined the flagellar apparatus of cryptomorphic C. curvata by transmission electron microscopy. The major components of the flagellar apparatus are the non-keeled rhizostyle (Rhs), striated fibrous root (SR), striated fiber-associated microtubular root (SRm), mitochondrion-associated lamella (ML), and two types of microtubular roots (3r and 2r). The non-keeled Rhs originate at the ventral basal body and consist of two types of microtubule bands extending together into the middle of the cell. The SR and SRm extend parallel to the left side of the cell. The ML originates from the ventral basal body and is a plate-like fibrous structure associated with mitochondria. The 3r extends from the dorsal basal body toward the dorsal anterior of the cell. The 2r originates between the two basal bodies and extends shortly to the left of the cell. The overall configuration of the flagellar apparatus is most similar to that previously reported for C. pyrenoidifera. These results demonstrate that the features of the flagellar apparatus are useful for distinguishing closely related species and inferring phylogenetic relationships among taxa.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.4867-4871
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• 2012

Cervical cancer is a leading cause of morbidity and mortality in women worldwide. Although the human papillomavirus (HPV) is considered the major causative agent of cervical cancer, yet the viral infection alone is not sufficient for cancer progression. The etiopathogenesis of cervical cancer is indeed complex; a precise understanding of the complex cellular/molecular mechanisms underlying the initiation, progression and/or prevention of the uterine cervix is therefore essential. Autophagy is emerging as an important biological mechanism in targeting human cancers, including cervical cancer. Furthermore, autophagy, a process of cytoplasm and cellular organelle degradation in lysosomes, has been implicated in homeostasis. Autophagic flux may vary depending on the cell/tissue type, thereby altering cell fate under stress conditions leading to cell survival and/or cell death. Autophagy may in turn govern tumor metastasis and subsequent carcinogenesis. Inflammation is a known hallmark of cancer. Vascular insufficiency in tumors, including cervical tissue, leads to depletion of glucose and/or oxygen perturbing the osmotic mileu causing extracellular acidosis in the tumor microenvironment that may eventually result in autophagy. Thus, targeted manipulation of complex autophagic signaling may prove to be an innovative strategy in identification of clinically relevant biomarkers in cervical cancer in the near future.

• Applied Microscopy
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• v.40 no.4
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• pp.253-259
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• 2010

The ultrastructure of sperms in testes of the pond smelt (Hypomesus nipponensis) was investigated using electron microscopes. The whitish testis was located between swim bladder and intestine. Especially, the left testis was larger than the right testis. The sperm was approximately $26\;{\mu}m$ in length. The sperm had an oval head and the acrosome was not found. The nucleus was about 400 nm in diameter and chromatin was incompletely condensed. The nuclear fossa deeply formed in sperm head and two centrioles were located in the fossa. The mitochondrium was observed only one in midpiece of the sperm and a motile flagellum consisted of an axoneme with a typical 9+2 pattern of microtubule. Also, the tail of the sperm has axonemal fins.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.18-24
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• 1999

Kinesin has been discovered in Saccharomyces cerevisiae, Aspergillus nidulans, and Drosophila melanogaster and it has major roles in the movemenl of chromosomes and separation of spindle poles. In this study, a gene encoding kinesin heavy chain in Schizosaccharo~n)~ces pombe was cloned by using the polymerase chain reaction with degenerated primcrs corresponding to highly conserved regions of the kinesin heavy chain motor domain. The kinesin gene in S pombe contains an open reading frame of 2496 base pairs and encodes a kinesin prolein of 832 amino acids with a molecular weight of 96 kd. From thc comparison of the predictcd amino acids of the newly cloned kinesin, the kinesin in S. pornbe belongs to the C-terminal motor subfamily of kincsin-related protein.

• Applied Microscopy
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• v.21 no.1
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• pp.46-62
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• 1991

The intermediate filament is one of the most important constituents of the intracytoplasmic cytoskeleton microtubule, actin, myosin and intermediate filament. It is composed of keratin, desmin, vimentin, neurofilament and glial filament, and has important role as a cellular marker, epithelial or mesenchymal origin. So it will be important to differentiated from some poorly or undifferentiated neoplasm to provide adequate therapeutic modalities. This study was performed by using immunohistochemical staining and electron microscopic observation to find out intermediate filaments of epithelial and non-epithelial tumor cells evaluate the degree of differentiation in tumors and therefore to provide some diagnostic and therapeutic modalities. The materials consisted of 83 epithelial and non-epithelial elements bearing 23 normal control, 28 epithelial tumors, and 32 non-epithelial tumors, that are resected for definite treatment at Chosun University Hospital from June, 1988 to June, 1990. Immunohistochemical stain for keratin, desmin and vimentin, and electron microscopic study were performed in all cases. The results obtained were as follows. 1. Immunohistochemical stain for intermediate filament were very useful diagnostic aid for differentiated epithelial tumor to non-epithelial tumor in diagnostic neoplasia. 2. In the electron microscopic finding, the size of intermediate filaments were possible differentiated to cell components of epithelial tumor and non-epithelial tumors.

• Genomics & Informatics
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• v.17 no.3
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• pp.27.1-27.9
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• 2019

Supernumerary B chromosomes were found in Lilium amabile (2n = 2x = 24), an endemic Korean lily that grows in the wild throughout the Korean Peninsula. The extra B chromosomes do not affect the host-plant morphology; therefore, whole transcriptome analysis was performed in 0B and 1B plants to identify differentially expressed genes. A total of 154,810 transcripts were obtained from over 10 Gbp data by de novo assembly. By mapping the raw reads to the de novo transcripts, we identified 7,852 differentially expressed genes (log₂FC > |10|), in which 4,059 and 3,794 were up-and down-regulated, respectively, in 1B plants compared to 0B plants. Functional enrichment analysis revealed that various differentially expressed genes were involved in cellular processes including the cell cycle, chromosome breakage and repair, and microtubule formation; all of which may be related to the occurrence and maintenance of B chromosomes. Our data provide insight into transcriptomic changes and evolution of plant B chromosomes and deliver an informative database for future study of B chromosome transcriptomes in the Korean lily.