• Journal of Sericultural and Entomological Science
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• 제25권2호
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• pp.1-31
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• 1984

Flacherie, as one of the most prevalent silkworm diseases, causes severe economic damage to sericultural industry and its pathogens have been proved to be flacherie virus (FV) and densonucleosis virus (DNV). Multiplications of the viruses in the larvae of the silkworm, Bombyx mori, were studied by the sucrose density gradient centrifugation and electron microscopy. The quantitative and qualitative changes of nucleic acids and proteins were investigated from the midgut and hemolymph in the silkworm larvae infected separately with FV and DNV. The histopathological changes of epithelial cells of infected midgut also were examined by an electron microscope. 1. Purified fractions of FV or DNV in a sucrose density gradient centrifugation yielded one homogenous and sharp peak without a shoulder, suggesting no heterogenous materials in the preparation. Electron microscopy also revealed that FV and DNV were spherical particles, 27nm and 21nm in diameter, respectively. 2. Silkworm larvae showed a decrease in body weight on the 6th day and in midgut weight on the 3rd day after inoculation with FV or DNV. 3. DNA content was higher in the midgut when infected with FV or DNV, but the hemolymph of the infected larvae showed no difference during first 6 days after inoculation, after which DNA concentration declined rapidly. 4. RNA synthesis of silkworm larvae infected separately with FV and DNV was stimulated in the midgut, but RNA content was reduced in the hemolymph at the early stage of virus multiplication. At the late stage of virus multiplication, however, it was extremely reduced in both midgut and hemolymph. 5. The concentration of protein in the midgut and hemolymph of silkworm larvae infected separately with FV and DNV showed no difference from that of the healthy larvae at the early stage of virus multiplication, but it was significantly reduced at the late stage of virus multiplication. 6. There was no difference in the electrophoretic patterns of RNAs extracted from the midgut of healthy or virus-infected larvae. 7. The electrophoresis of proteins extracted from the midgut infected with FV or DNV, when carried out on the 1st and 5th day after virus inoculation, showed no difference from that of the healthy larvae. But, there was an additional band with medium motility in the proteins on the 8th day after virus inoculation, while a band with low mobility shown in the proteins of healthy larvae disappeared in the infected larvae. However, a band with high mobility in the healthy larvae was separated into two fractions in the infected larvae. 8. The electrophoretic pattern of hemolymph proteins of the silkworm larvae infected separately with FV and DNV was similar to that of the healthy larvae, but the concentration of hemolymph proteins in the infected larvae was lower than that of the healthy larvae at the late stage. 9. Two types of inclusion bodies were shown by the double staining of pyronin-methyl green in the columnar cell of the midgut on the 8th day after FV inoculation. 10. Electron microscopy of the infected midgut revealed that the 'cytoplasmic wall' of the goblet cell thickened on the 5th day after FV inoculation and several types of the cytopathogenic structures, such as virus$.$specific vesicles, virus particles, linear structures, tubular structures, and high electron-dense matrices were observed in the cytoplasm of the goblet cell. The virus particles were also observed in the microvilli and the structures similar to spherical virus particles were observed around the virus-specific vesicles, suggesting the virus assembly in the cytoplasm. 11. Fluorescence micrograph of the infected midgut stained with acridine orange showed that the nucleus, the site of DNV multiplication in the columnar cell, enlarged on the 5th day after virus inoculation. 12. Electron microscopic examination of DNV infected midgut revealed that the nucleolus of the columnar cell was broken into granules and those granules dispersed into apical region of the nucleus on the 5th day after virus inoculation. On the 8th day after inoculation, it was also observed that the nucleus of the columnar cell was full with the high electron-dense virogenic stroma which were similar to virus particles. These facts suggest that the virogenic stroma were the sites of virus assembly in the process of DNV multiplication.

• Journal of the Korean Society of Food Science and Nutrition
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• 제31권5호
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• pp.924-930
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• 2002

Ixeris dentata extracts exllibited antimicrobial activity against some bacteria and fungi. Also EtOH extracts showed strong antioxidant activity and RC$_{50}$ value was 28 $\mu\textrm{g}$/mL. The inhibitory effect of Ixeris dentata on the mutagenicity in Salmonella and cytotoxicity on cancer cell were studied. Ixeris dentata extracts showed anti-mutagenic effects of 78.83 and 75.96% on B(a)P in S. typhimurium TA98 and Th100, respectively. These extracts showed 78.72% antimutagenicity on TA100 against MNNG. The Ixeris dentata extract with strong antimutagenic activities was further fractionated by hexane, ethyl acetate, butanol and water. Butanol fraction was found to be highest in antimutagenic activity against MNNG than the other fractions. Butanol fraction of Ixreis dentate revealed the highest cytotoxicity against AS49 human lung carcinoma cells in which cell growth was inhibited by 93.75% at 375 $\mu\textrm{g}$/mL. Hexane fraction of ixeris dentate exhibited 68.56% inhibition against MCF-7 human breast adenocarcinoma cells at 500 $\mu\textrm{g}$/mL. Hexane fraction of Ixeris dentata exhibited 84.91% inhibition against Hep 3B human hepatocellular carcinoma cells at 500 $\mu\textrm{g}$/mL. From these results, it is considered that Ixeris dentata has strong antimutagenic and anticancer effects in vitro. However, these extracts and fractions did not show any cytotoxic effect against 293 cells.

• Parasites, Hosts and Diseases
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• 제31권3호
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• pp.249-258
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• 1993

Naegleria fowleri is the cause of primary amoebic meningoencephalitis in man, IL-2 levels after stimulation of T lymphocytes by PHA or N.fowleri lysates. the amounts of T lymphocyte subsets and the blastogenic responses of T lymphocytes in mice after Infected with pathogenic N. fowleri were studied comparing between two study groups, one $1{\;}{\times}{\;}10^4$ trophozoites inoculated mice and the other $1{\;}{\times}{\;}10^5$ trophozoites inoculated mice. All experimental samples were obtained on the day 7, 14 and 24 after inoculation. The mice inoculated with $1{\;}{\times}{\;}10^4$ trophozoites showed a 14.3% mortality rate, and 72.2% in the mice inoculated with $1{\;}{\times}{\;}10^5$ trophozoites. The IL-2 levels on day 14 of two experimental groups were significantly decreased as compared with the control group. Thy 1.2+T cells in the total spleen Iymphocytes of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group on day 7 were significantly increased compared with the control group. There was no significant difference between $1{\;}{\times}{\;}10^4$ trophozoites inoculated group and the control group. $L3T4^{+}{\;}T$ cells and $Ly2^{+}$ T cells in the total spleen Iymphocytes of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group on day 7 were sigrlificantly increased compared with the control group. The DNA S fraction of T cells in the spleen of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group was significantly increased on day 7. The amount of S fractions of DNA were sequentially decreased on day 14 and 24 but they were also signiacantly increased compared with the control group. The results obtained in the experiments indicats that cell mediated immunity after N.fowleri infection acts on very important host's protection immunity around the 7th day after infection. IL-2 level was much suppressed on day 14 which resulted from the exhaustion of host immune response. It was observed that the level of IL-2 production ability and the amounts of T lymphocytes subsets and the blastogenic responses of T lymphocytes were not well correlated during the observation period.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• 제3권1호
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• pp.129-147
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• 1997

Radiotherapy is an irreplaceable method of cancer treatment. But it has several side effects, especially damages to the hemopoietic and Immune system. Therefore radioprotectors are required to treat cancer successfully. A lot of Herbs and Herbal prescriptions are reported to have radioprotective effects. Above all, those to support the healthy energy and strengthen the body resistance are found more effective. This study was performed to evaluate the radioprotective effects of prescription Shenrong Fuzheng Tang(S.F.T.), which consists of 16 kinds of herbs. We investigated proliferation of murine splenocytes, secretion of colony-stimulating-factors(CSFs), immunocompetence after irradiation in-vitro, and Endogenous spleen colony assay, survival assay in-vivo. When splenocytes were cultured with Shenrong Fuzheng $Tang(S.F.T.)(500{\mu}g/ml)$, proliferation was enhanced 5.7 times compared to control cultured with medium alone(p<0.05) and, showed highest proliferation at 4th day after incubation. In order to evaluate stimulation of hemopoiesis of Shenrong Fuzheng Tang(S.F.T.), the supernatant of splenocytes cultured with optimal concentration of Shenrong Fuzheng Tang(S.F.T.) was used to measure CSFs secretion. The result showed enhanced secretion of colony-stimulating-factors (CSFs) compared to control(p<0.05). To evaluate the protective effect of lymphocytes from irradiation, proliferation of splenocytes stimulated by LPS and ConA after incubation with Shenrong Fuzheng Tang(S.F.T.) for 24h Prior to Irradiation$(1{\sim}3\;Gy)$ was measured. The results showed higher proliferation of Shenrong Fuzheng Tang(S.F.T.) treated cells than that of non-treated cells. And percentage increases of irradiated splenocytes per non-irradiated splenocytes were also higher in Shenrong Fuzheng Tang (S.F.T.)-treated cells than control. Endogenous spleen colony assay. to evaluate the protection of hemopoietic cells from irradiation, showed increased number of colonies(p=0.03) in Shenrong Fuzheng Tang(S.F.T.) treated murine spleen$(10.3{\pm}1.9)$ compared to non-treated murine spleen$(3.4{\pm}0.8)$. Survival time of mice irradiated with lethal dose of ${\gamma}-ray(9Gy)$ was prolonged in Shenrong Fuzheng Tang(S.F.T.) treated group prior to irradiation as compared to non-treated group. According to these results we can suggest that prescription Shenrong Fuzheng Tang(S.F.T.) has radioprotective effects and can be used to protect the hemopoietic and immune system from damages of anti-cancer radiotherapy.

• Korean Journal of Ecology and Environment
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• 제46권4호
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• pp.588-595
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• 2013

This study investigated the influence of temperature and $CO_2$ increase on phytoplankton growth and community structure during cold water season (spring) in Lake Paldang, Korea. Four experimental treatments of temperature and $CO_2$ manipulation were prepared in the laboratory batch culture: (1) Control; ambient low temperature ($6{\pm}2^{\circ}C$) and low $CO_2$ (air level, $400mgL^{-1}$), (2) T1; low temperature and high $CO_2$ ($800mgL^{-1}$), (3) T2; high temperature ($20{\pm}2^{\circ}C$) and low $CO_2$, (4) T3; high temperature and high $CO_2$. Algal growth experiment was carried out for 10 days under the light intensity of $70{\mu}mol\;m^{-2}s^{-1}$ (L :D=24 : 0). The level of pH decreased in both T1 and T3, due to dissolution of added $CO_2$. The dominant phytoplankton species of ambient water, Cyclotella meneghiniana succeeded to Fragilaria capucina var. gracilis in high-temperature treatment groups (T2 and T3). Cyanobacteria were very rare at the beginning of the experiment, while Oscillatoria limnetica appeared in only high-temperature groups (T2 and T3) at $6{\sim}7^{th}$ day. $CO_2$ addition in ambient temperature (T1) induced the highest phytoplankton growth, and thereby producing the highest average cell density of $3.27{\pm}0.33\;10^4\;cells\;mL^{-1}$, followed by T2 ($2.65{\pm}0.26\;10^4\;cells\;mL^{-1}$), T3 ($2.09{\pm}0.16\;10^4\;cells\;mL^{-1}$), and Control ($1.86{\pm}0.13\;10^4\;cells\;mL^{-1}$) (F=7.167, p=0.000). In summary, temperature increase changed the phytoplankton community structure and $CO_2$ increase promoted the phytoplankton growth during the cold spring season in Lake Paldang, suggesting a potential effect of climate change on freshwater phytoplankton.

• Korean Journal of Animal Reproduction
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• 제24권4호
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• pp.365-373
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• 2000

The purpose of this study was to investigate the effects of the fusion pulses and fusion media on fusion rate and the development of embryos produced by somatic cell nuclear transfer in Hanwoo (Korean cattle). Nuclear donor cumulus and fetal fibroblast cells were cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum at 38.5$^{\circ}C$ in a humidified atmosphere of 5% $CO_2$in air. The in vitro matured oocytes were enucleated and then the isolated donor cells were introduced. The cumulus cell and cytoplast were fused using one pulse of 70 volts for 40$mutextrm{s}$, two pulses of 70 volts for 40$mutextrm{s}$ and one pulse of 180 volts for 15$mutextrm{s}$. The fetal fibroblast cell and cytoplast were fused using one pulse of 180 volts for 15$mutextrm{s}$ or 30$mutextrm{s}$. The cumulus cell and cytoplast were fused using mannitol and Zimmerman cell fusion medium (ZCFM) as a fusion medium. The fused embryos were activated after the fusion with 10 $\mu$M calcium ionophore for 5 min and 2 mM 6-dimethyl- aminopurine for 3 h. The nuclear transfer embryos were cultured in 500 ${mu}ell$ well of modified CR1aa supplemented with 3 mg/$m\ell$ BSA in th $\varepsilon$ four well dish cove red with mineral oil. After 3 days culture, culture medium was changed into modified CRlaa medium containing 1.5 mg/$m\ell$ BSA and 5% FBS for 4 days. The incubation environment was 5% $CO_2$, 5% $O_2$, 90% $N_2$ at 38.5$^{\circ}C$. When the cumulus cells were fused with enucleated oocytes by three different fusion pulses, one pulse of 180 volts for 15 $mutextrm{s}$ yielded the highest fusion rate and developmental rate to blastocyst among the pulses (P＜0.05). When the fetal fibroblast cells were fused with enucleated oocytes, one pulse of 180 volts for 30$mutextrm{s}$ yielded significantly higher fusion rate compared with that for 15 $mutextrm{s}$(P＜0.05). The present result indicates that the fusion rate between karyoplast and cytoplast was affected by the cell type and the optimal fusion condition was different according to cell type or size. When the fusion was conducted by the use of mannitol and ZCFM, the fusion rate was 71.2% and 65.8%, respectively. The developmental rates to blastocyst were 37.8% and 39.8%, respectively. There was no significant difference between two fusion media in the developmental rate of cumulus cell nuclear transfer embryos. These results indicate that optimal electric current should be selected according to cell type.

• The Journal of Korean Society of Virology
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• 제26권2호
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• pp.151-162
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• 1996

Pseudorabies is caused by Pseudorabies virus (PRV: Aujeszky's disease virus) of Herpesviridae that is characterized by 100 to 150nm in size with a linear double-stranded DNA molecule with of approximately $90{\times}10^6Da$. This disease affects most of domestic animals such as swine, cattle, dog, sheep, cat, chicken, etc. causing high mortality and economic losses. In swine, young piglets show high mortality and pregnant sows, reproductive failures. However the adult swine reveals no clinical signs in general. But they become a carrier state and play an important role for propagation of the disease. In this study, the nucleotide sequence of major casid protein gene of PRV, Yangsan strain isolated from the diseased swine in Korea was analyzed, and the recombinant MCP was produced by expression of the MCP gene in Sf-9 cell using baculovirus transfer vector system. As result, in BamHI digestion, MCP gene locus of PRV YS strain showed different from that of Indiana S strain. The patterns of enzyme mapping were also found to be unidentical each other. The sequence of the MCP gene partially analyzed showed 98.09% identity to Indiana S strain. The expression of MCP in Sf-9 cell cotransfected by pVLMCP-44 baculovirus expression vector was characterized by Southern blot hybridization, immunofluoresent and immunocytochemical tests, SDS-PAGE and Western blotting. The rMCP with M.W. 142kDa was most effectively expressed in Sf-9 cells at the 3-4th days post inoculation of the recombinant baculovirus by 2 moi.

• Proceedings of the KIEE Conference
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1034-1038
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• 1995

The purpose of this study is to research and develop $TiS_2$ composite cathode for lithium polymer battery(LPB). $TiS_2$ electrode represent a class of insertion positive electrode used in Li secondary batteries. In this study, we investigated preparation of $TiS_2$ composite cathode and AC impedance response of $TiS_2$ composite/SPE/Li cells as a function of state of charge(SOC) and cycling. The resistance of B type cell using $TiS_2PEO_8LiClO_4PC_5EC_5$ composite cathode was lower than that of A type cell using $TiS_2PEO$ composite cathode. The cell resistance of B type cell is high for the first few percent discharge, decreases for midium discharge and then increases again toward the end of discharge. We believe the magnitude of the cell resistance is dominated by passivation layer impedance and small cathode resistance. AC impedance results indicate that the cell internal resistance increase with cycling, and this is attributed to change of passivation layer impedance with cycling. The passivation layer resistance($R_f$) of B type cell decreases for the 2nd cycling and then increases again with cycling. Redox coulombic efficiency of B type cell was about 141% at 1st cycle and 100% at 12th cycle. Also, $TiS_2$ specific capacity was 115 mAh/g at 12 cycle.

• The Journal of the Korea Contents Association
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• 제9권4호
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• pp.275-285
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• 2009

During an 8 month period from January to August 2007, complete blood count (CBC) samples were taken from various wards and from the outpatient department at Samsung Medical Center. In order to determine whether or not the total white blood cells were over counted, results were obtained from both the 4Diff/channel and the white blood cell channel from the automated blood analysis equipment from S company for comparison. Among patients who were on long term treatments, the number of cases determined to be over counted by comparing the WBC counts during this 8 month period was 25. Clinical chemistry tests were also conducted on the same day on the 25 samples taken. 68% of the patients showed to exceed normal range of aspartate transaminase (AST) and alanine aminotransferase (ALT) indicating abnormal liver function, and the total bilirubin range were also in excess in 60% of the total samples taken. Further clinical information which was obtained from the patients showed 98% of the patients were administered with cefepime which is the 4th generation cephalosporin at the time when the WEC were over counted. It is assumed that a multiple of factors investigated caused the over count of the WEC rather than a single factor.

• Journal of Acupuncture Research
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• 제28권3호
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• pp.33-42
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• 2011

Objectives : This study was performed to evaluate the effects of Scutellariae radix (SR) water extract on locomotor dysfunction induced by spinal cord injury (SCI) in rats. Methods : SCI was induced mechanical contusion following laminectomy of 10 th thoracic vertebra in Sprague-Dawley rats. SR was orally given once a day for 7 days after SCI. Neurological behavior was examined with the Basso-Beattie-Bresnahan locomotor rating scale. Tissue damage and nerve fiber degeneration were examined with cresyl violet and luxol fast blue (LFB) histochemistry. Using immunohistochemistry, cellular damages to neurons and nerve fibers were examined MAP-2. Results : 1. SR significantly ameliorated the locomotor dysfunction of the SCI-induced rats. 2. SR significantly reduced the number of motor neurons in the ventral horn of the SCI-induced rat spinal cord. 3. SR attenuated the reduction of nerve fiber shirnakage and degeneration of the SCI-induced rat spinal cord. 4. SR attenuated the reduction of MAP-2 positive cells in the peri-lesion of the SCI-induced rat spinal cord. Conclusions : These results suggest that SR improves the locomotor dysfunction of SCI by reducing degeneration of nerve fibers and motor neuron shrinkage in the ventral horn.