• Proceedings of the KIEE Conference
• /
• 2005.11a
• /
• pp.103-105
• /
• 2005

The importance of protecting people from harsh weather conditions cannot be over-emphasized and the way to. do so should be sought vigorously. The most well known and widely used weather protection fabric in the current industry is $Gor-Tex.^1$ However, the Gore-Tex membrane cannot be attached to cotton or other natural fibers so it's use is not suitable for clothing such as underwear. If the exterior of cotton fabric can be made to be hydrophobic without sacrificing the comfort and breathability, the result will be a cotton fabric with the weather protection capability equivalent to Gore-Tex as well as the ability to provide the best wear comfort. However, this should be done without using toxic and expensive gases to be environmentally friendly and cost effective. Therefore, our approach for hydrophobic treatments of fabric and metal surfaces is to utilize a plasma-based technique. In general, plasma processes do not produce chemical wastes or waste disposal problems and they are fully automated.

• BMB Reports
• /
• v.35 no.3
• /
• pp.297-301
• /
• 2002

Membrane lipid peroxidation processes yield products that may react with DNA and proteins to cause oxidative modifications. The oxyR gene product regulates the expression of enzymes and proteins that are needed for cellular protection against oxidative stress. Upon exposure to tert-butylhydroperoxide (t-BOOH) and 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH), which induce lipid peroxidation in membranes, the Escherichia coli oxyR overexpression mutant was much more resistant to lipid peroxidation-mediated cellular damage, when compared to the oxyR deletion mutant in regard to growth kinetics, viability, and DNA damage. The deletion of the oxyR gene in E. coli also resulted in increased susceptibility of superoxide dismutase to lipid peroxidation-mediated inactivation. The results indicate that the peroxidation of lipid is probably one of the important intermediary events in free radical-induced cellular damage. Also, the oxyR regulon plays an important protective role in lipid peroxidation-mediated cellular damage.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.4
• /
• pp.1643-1647
• /
• 2016

Since their discovery in 1940, it has been well established that gangliosides are associated with a number of biological pathways and cellular processes such as growth, differentiation and toxin uptake. Gangliosides are glycosphingolipids containing neuraminic acid which are expressed on the plasma membrane of cells particularly in the nervous system. Heterogeneity and structural variation in the carbohydrate chains of gangliosides contributes to unique features of each of these molecules. Thirty five years ago it was discovered that aberrant glycosylation occurs in a variety of human cancers, including aberrant glycosylation of gangliosides. Ganglioside expression in terms of quality and quantity varies in different cancers and different roles may be played. Gangliosides, by affecting the immune system, including esxpression of cytokines and adhesion molecules, may inhibit anti-tumor mechanisms, as well as having direct impact on angiogenesis, cell movement and metastasis. It should be noted that different kinds of gangliosides do not all act by the same mechanisms.

• Clinical and Experimental Pediatrics
• /
• v.63 no.8
• /
• pp.291-300
• /
• 2020

Advances in autoimmune encephalitis studies in the past 10 years have led to the identification of new syndromes and biomarkers that have transformed the diagnostic approach to the disorder. The disorder or syndrome has been linked to a wide variety of pathologic processes associated with the neuron-specific autoantibodies targeting intracellular and plasma membrane antigens. However, current criteria for autoimmune encephalitis are quite dependent on antibody testing and responses to immunotherapy, which might delay the diagnosis. This form of encephalitis can involve the multifaceted presentation of seizures and unexpected behavioral changes. The spectrum of neuropsychiatric symptoms in children is less definitive than that in adults, and the incorporation of clinical, immunological, electrophysiological, and neuroradiological results is critical to the diagnostic approach. In this review, we document the clinical and immunologic characteristics of autoimmune encephalitis known to date, with the goal of helping clinicians in differential diagnosis and to provide prompt and effective treatment.

• Journal of Microbiology and Biotechnology
• /
• v.22 no.4
• /
• pp.547-554
• /
• 2012

Chromium is generated from several industrial processes. It occurs in different oxidation states, but Cr(III) and Cr(VI) are the most common ones. Cr(VI) is a toxic, soluble environmental contaminant. Some bacteria are able to reduce hexavalent chromium to the insoluble and less toxic Cr(III), and thus chromate bioremediation is of considerable interest. An indigenous chromium-reducing bacterial strain, Rb-2, isolated from a tannery water sample, was identified as Ochrobactrum intermedium, on the basis of 16S rRNA gene sequencing. The influence of factors like temperature of incubation, initial concentration of Cr, mobility of bacteria, and different carbon sources were studied to test the ability of the bacterium to reduce Cr(VI) under variable environmental conditions. The ability of the bacterial strain to reduce hexavalent chromium in artificial and industrial sewage water was evaluated. It was observed that the mechanism of resistance to metal was not due to the change in the permeability barrier of the cell membrane, and the enzyme activity was found to be inductive. Intracellular reduction of Cr(VI) was proven by reductase assay using cell-free extract. Scanning electron microscopy revealed chromium precipitates on bacterial cell surfaces, and transmission electron microscopy showed the outer as well as inner distribution of Cr(VI). This bacterial strain can be useful for Cr(VI) detoxification under a wide range of environmental conditions.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.11
• /
• pp.2028-2036
• /
• 2017

The Escherichia coli K-12 and B strains are among the most frequently used bacterial hosts for scientific research and biotechnological applications. However, omics analyses have revealed that E. coli K-12 and B exhibit notably different genotypic and phenotypic attributes, even though they were derived from the same ancestor. In a previous study, we identified a limited number of proteins from the two strains using two-dimensional gel electrophoresis and tandem mass spectrometry (MS/MS). In this study, an in-depth analysis of the physiological behavior of the E. coli K-12 and B strains at the proteomic level was performed using six-plex isobaric tandem mass tag-based quantitative MS. Additionally, the best lysis buffer for increasing the efficiency of protein extraction was selected from three tested buffers prior to the quantitative proteomic analysis. This study identifies the largest number of proteins in the two E. coli strains reported to date and is the first to show the dynamics of these proteins. Notable differences in proteins associated with key cellular properties, including some metabolic pathways, the biosynthesis and degradation of amino acids, membrane integrity, cellular tolerance, and motility, were found between the two representative strains. Compared with previous studies, these proteomic results provide a more holistic view of the overall state of E. coli cells based on a single proteomic study and reveal significant insights into why the two strains show distinct phenotypes. Additionally, the resulting data provide in-depth information that will help fine-tune processes in the future.

• Applied Microscopy
• /
• v.24 no.2
• /
• pp.93-104
• /
• 1994

Six types of hemocytes were identified in adult grasshopper, Euprepocnemis shirakii Bolivar. The morphological and ultrastructural characteristics of these cells were characterized by phase contrast, scanning and transmission electron microscope. The prohemocytes are small and spherical cells with large nucleus. The plasmatocytes are spindle shaped or polymorphic cells which show numerous cytoplasmic processes on the cell surface and they have lysosomes and vesicles that may be involved in phagocytic function. Especially, multivesicular bodies are observed in the polymorphic cells. The granulocytes I are spherical shaped cells. They are characterized by a number of electron dense granules measuring $0.2-0.3{\mu}m$ in average diameter and marginal band of microtubules which are always in close proximity to the cell membrane. The granulocytes II are oval or spindle-shaped cells. They contain large electron dense granules measuring $0.5-0.8{\mu}m$ in average diameter. Their cytoplasm is filled with numerous granules. The spherulocytes contain large amounts of spherules that most of their cytoplasm. Spherules filled with fine granules or flocculent materials. The oenocytoids are large spherical cells with few cytoplasmic organelles. Their cytoplasm contains peculiar aspect of motochondria and numerous polyrobosome.

• New & Renewable Energy
• /
• v.1 no.4 s.4
• /
• pp.49-54
• /
• 2005

There is close relation between the heat generation in the fuel cell stack and the fuel performance. In PEM fuel cell vehicles, the stack coolant temperature is about $65^{\circ}C$, which is far lower than that for general automobile engine. Therefore, it is hard to release heat generated in the stack by using a radiator of limited size because of the reduced temperature difference between the coolant and the ambient air. In this study, indirect stack cooling system using $CO_2$ heat pump was designed and its stack cooling performance in releasing heat to the ambient was investigated. This work focuses on a series of processes that grasp the relation among the fuel cell power, the radiator capacity and the stack temperature. The purpose of this work is to find out a way to properly release sufficient amount of heat through the finite sized radiator, so that the slack power generation can not be deteriorated due to the stack temperature increase. The optimization between the compressor power consumption and the fuel cell output power can be carried out to maximize the performance of fuel cell system.

• Korean Journal of Veterinary Research
• /
• v.35 no.1
• /
• pp.55-65
• /
• 1995

Ultrastructures of pancreatic endocrine cells containing glucagon, insulin, somatosratin and pancreatic polypeptide were studied in the pancreas of the Korean native goat by immunohistochemical and elecron microscopy. Glucagon immunoreatctive cells were round or fusiform in shape and contained secretory granules of 200-260 nm in diameter. The secretory granules were high in electron density and had a halo between the limiting membrane and the central granule core. Insulin immunoreactive cells were round or oval in shape, and contained various sizes of secretory granules from 135 to 300 nm in diameter. The secretory granules were low or moderate electron density and had a variform halo. Somatostatin immunoreactive cells were elliptical or fusiform shape with cytoplasmic processes. They contained the secretory granules of 140-320 nm with moderate electron densities. Pancreatic polypeptide immunoreactive cells were elliptical or fusiform and contained small secretory granules with high electron densities. The secretory granules were 120-230 nm in diameter and the least in number.

• Journal of Pharmaceutical Investigation
• /
• v.37 no.5
• /
• pp.281-286
• /
• 2007

For transdermal delivery of porcine placenta extract (PPE), various emulsion formulations were prepared and evaluated. Polysorbate surfactants were used as emulsifiers and various C-18 unsaturated fatty acids as enhancers. The skin permeation of PPE was tested using a cellulose nitrate membrane-loaded Franz cell apparatus. Among emulsifiers, Tween 20 provided higher penetration effect than did Tween 80. Meanwhile, of various fatty acids, linolenic acid (18:3) revealed the highest skin permeation of PPE than the other C-18 unsaturated fatty acids. Stability of PPE emulsions was determined by cycles of freezing and thawing processes. The stability of emulsions depended on the percentage of Tween 20. Minimum 20% of Tween 20 was required to stabilize emulsions at room temperature for several days. Taken together, our results suggest that Tween 20 and linolenic acids might be key components to formulate PPE emulsion to provide the desirable skin permeability and stability.