• Parasites, Hosts and Diseases
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• v.29 no.4
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• pp.381-388
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• 1991

Trichomonas vaginalis is a parasitic nagellate in the urogenital tract of human. Innate cytotonicity of macrophages against T. vaginalis has been recognized, but any report on the cytotoxicity of Iymphokine-activated macrophages to T vaginalis is not yet available. The present study aimed to elucidate the Iymphokine-activated cell mediated cytotoxic effect against T. vaginalis by mouse peritoneal macrophages. Cytotoxicity was measured by counting the release of $^3H-thymidine$ from prelabeled protozoa, and tested in U-bottom microtiter plates. Nitrite concentration in culture supernatants was measured by standard Griess reaction. The results obtained are as follows: 1, The cytotoxicity of macrophages was increased by addition of rIL-2 or $rIFN-{\gamma}$$. 2, Cytotoxicity of macrophages was reduced by addition of rIL-4 to rOM-CSV, rIL-2 or $rIFN-{\gamma}$. 3. Crude Iymphokine mixed with anti-lL-2 decreased the cytotoxity of macrophages. 4. In case of macrophages cultured with $rIFN-{\gamma}$ or rIL-4, the concentration of nitrite was related with cytotokity of macrophages against T. vaginalis, but the cytotoxicity of macrophages cultured with rIL-2 and $rIFN-{\gamma}$ was decreased in spite of its high production of llitrite. From the results obtained, it is assumed that rIL-2 and $rIFN-{\gamma}$ enhance the cytotoxicity of macrophages while rIL-4 inhibits the cytotoxicity against T. vaginalis, and that the production of nitrite does not relate with the cytotoxicity of macrophages, but nitric oxide may play a role as an inhibitory factor on the proliferation of T. vaginalis.

• Parasites, Hosts and Diseases
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• v.25 no.1
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• pp.69-82
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• 1987

The prevalences of the cuke belonging to genus Metagonimus hove been reported along the upper stream of inhabitants by several workers since 1980, however the taxonomical problems of the fluke was not yet settled. The larval flukes; cercaria and metacercaria as well as their intermediate hosts, and adult were studied in order to identify the Mepagonimus in the areas. The results obtained are summarized as follows: 1. The snails, Semisulcospira globus were collected (rom the three different localities along the upper stream of the River. The cercariae were found from 125(7.2%) out of 1,730 snails by natural emerging method, and were identified into 5 species including Metagenimus sp. (3.7%), Pseudexorchis major(1.4%), Cercaria nipponensis (0.9%), Cercaria incerpa(0.6%), and Cercaria yoshidae(0.6%). Cercariae of Metagonimus species had four to dye oral spines on its anterior of the first line. 2. The cercariae of Metagonimus were experimentally exposed to goldfish. nfection rate was 22.9% out of 105 goldfish, and the encysted metacercariae were found in fins(86.7%) and on scales (13.7%) of the fishes, but not in their muscle, head or visceral organs. 3. Seven species of ask were caught in the Daecheong Reservoir and the upper stream. Infestations with metacercaria of Metagonimus were found 100% in Opsariichtys widens and the parasitized numbers of the metacercariae were observed from 250 to 2,400 per fish. In the upper stream, Zacco termmincki, Z. platypus and Pseudogobio esocinus were infected 100% with the metacercaria, on the other hand, the fishes caught in the reservoir showed the lower infestation rates, and a few metacercariae found in the fishes Carassius carassius and Cyprinus carpio in the reservoir and the stream. The majority of metacercariae was detected only on the scales of fishes. 4. In order to know the infectivity and the distribution patterns in the intestine of hosts, rats and dogs were infected with the metacercariae obtained from O. bidens and Z. platypus. In addition the metacercariae obtained from Z. temmincki, P. esocinus and goldfish were given to the rats. The recovery rates of the worms in the small intestine of dogs were higher (63.3~65.8%) than those of the rats (3.5~31.6%). The flukes were found mostly in the middle and the lower part of small intestine of the rats and the dogs, but no worm was collected in the upper part of the intestine of rats. 5. The sixte of adult flukes varied by the hosts. In the adult cukes, oral sucker was smaller than ventral sucker, and the right and left testes were located diagonally, the uterine tubules circled around the upper left testis. The average egg sixte was $29.1{\times}1.7{\mu\textrm{m}}$. According to the above results, the cukes belonging to genus Metagonimus distributed along the Geum River was concluded to be identical with Miyata type of M. yokogawai as that Saito had proposed.

• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.159-167
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• 1987

To analyse the antigen specificity of patients sera from 24 confirmed neurocysticercosis and a monoclonal antibody, SDS-PAGE using 10~15% linear gradient gel and EITB were done. Cystic fluid, saline extracts of scolex and of whole worm of C. cellulosae, saline extracts of sparganum, hydatid cyst fluid, saline extracts of Fasciola, Clonorchis and Paragonimus were used as antigen. Of protein bands in cystic fluid of C. cellulosae, patient sera reacted frequently to bands of 152, 94, 64, 48, 24, 15, 10 and 7kDa proteins. To saline extracts of scolex and whole worm of C. cellulosae, patients sera reacted frequently to 94, 64, 52, 39, 34, 15 and 10kDa bands. Two bands in sparganum extract (130 and 64kDa) and two bands in hydatid cyst fluid (52 and 27kDa) were cross-reacting bands with sera from cysticercosis patients. Saline extracts of Fasciola, ClonorchiJ and Paragonimus did 'not exhibit cross-reacting bands. Monoclonal antibody to cystic fluid of C. cellulosae was found to react with low molecular weight proteins of 15, 10 and 7kDa.

• Parasites, Hosts and Diseases
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• v.29 no.4
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• pp.339-354
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• 1991

Localization and characterization of the antigenic components of sparganum which induced IgG and IsM antibodies in the host were studied by immunohistochemical techniques and SDS-PAGT and Western blotting. The antigen recognized by IgG antibody of rats or mice which were immunised by infection or injection of crude extracts of metacestodes of Spirometra erinacei, was located in the parenchyme of sparganum, especially at the cortex and around the calcareous corpuscles. The immunoreaction was demonstrated not only in the encysted fibrous wall of host but around the arterioles or venules in the connective tissue of host. The antigen recognized by IgM antibody of rats or mice was also observed in the parenchyme of sparganum and in the connective tissue of host. By 5∼20% gradient SDS-PAGE and EIBT, we detected antigenic components by IgG and 1gG antibodies of the rat or mouse immunized by infection or injection of crude extract of spargana. Twenty-three antigenic bands from crude extracts of spargana were recognized by IgG antibody and 15 components by IgM antibody of immunized rats. Out of the bands recognized by IgG and IgM antibodies, 15 were cross-reacted each other. Twenty components of eBlcretory-secretory proteins from spargana were recognized by IgG, and 5 components by IgM antibody of immunized rats. By IgG and IgM antibodies of immunized mice, 16 components of crude extracts were recognized by IgG antibody and 9 components by IgM antibody. Twenty components of excretory-secretory preparation were recognized by IgG antibody and 5 components by IgM antibody. Thirteen components of crude extracts were cross-reacted by IgG antibody of rats and mice.

• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.168-180
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• 1987

This study was performed to observe histopathological changes and serological reactions in chronic anisakiasis of rabbits. Each rabbit was infected per os with 30 larvae of Anisakis type I. Their sera were collected chronologically and the rabbits were killed for histopathological examination, 3, 13, 20, 30, 60, 90 and 150 days after the infection. The results were summarized as below. 1. Most of the larvae were recovered from the stomach, but a few from the omentum, intestine, mesentery and abdominal wall. The recovery rates and distribution of worms by organ were not differed by duration of infection. 2. Histologically the lesion was abscess type on 13 days, i.e., the dead worms were surrounded by fibrinous exudate, histiocytes and thick zone of numerous inflammatory cells. After 30 days, histiocytes were found to invade the worms and the lesion was changing into abscessgranulomatous type. Also a calcified worm was found on the 30th day. After then the worms were observed to be dissolved slowly until 90 days. On 150 day, only one calcified worm was observed. 3. The levels of serum IgG antibody by ELISA reached their maximum 30 days after the infection. After then, it decreased slowly until 150 days after the infection. Above serological and histopathological findings indicated that antigenic stimulation from degenerating Anisakis larvae was the greatest during the first 30 days after infection. This period was corresponding with the beginning of worm resolution or calcification. Serologic test by ELISA would be a valuable tool for confirming chronic anisakiasis.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.201-210
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• 1995

This study aims to assess the possible strain-dependent variations in detection of ToxopLosmn antigens and antibodies. The virulent RH strain or avirulent Beverley strain of T gondii were injected into mice, intraperitoneally, and their antigens, antibodies and parasites were identified from the blood or tissues: liver, brain and spleen by ELISA, Western blot and PCR. In mice infected with RH strain, circulating antigens and parasitemia were first detected from 2 days after infection, and ToxopIasma DNA were found in the blood, liver, brain and spleen from 3 days after infection. It was impossible to detect specific IgM and IgG antibodies to T gondij and any specific band was not found by Western blot. In mice infected with Beverley strain, circulating antigens were detected between day 10 and day 35. The Toxoplusma DNA was found in the blood and liver from day 15 until day 60, and in the brain from day 20. But Toxoplosma DNA in the spleen were mainly detected between day 10 and day 30. The IgM antibodies were first appeared on day 10 post-infection, and were noted obviously increased between day 15 and 25. The IgG antibodies were first detected on day 15, and showed progressively increased titers. The antibody binding bands were specific according to infection period. Sera from mice infected with Beverley strain reacted mainly with the antigen of 27.5-kDa and 32.5-kDa. In conclusion, mice infected with RH strain revealed Toxoplosma antigens strongly, but not antibodies. However. mice infected with Beverley strain revealed both the Toxoplasma antigens and antibodies. The present results showed that immune responses are different between avirulent and virulent T gonnii.

• Parasites, Hosts and Diseases
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• v.36 no.1
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• pp.15-22
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• 1998

An in uitro culture technique was established for harvesting Strongwloides venezuelensis free-living infective larvae using a nutrient broth medium as a substitute for rat-feces in polyvinyl culture bags ($10{\;}{\times}{\;}12{\;}cm$). The egg hatch rate V) in sterile saline at different incubation temperatures (X) was expressed as the quadratic function, Y = $-0.192X^2$ + 8.673x - 19.550 (r = 0.901). The highest (100%) egghatch rate was observed at $25^{\circ}C$. A significant difference (p<0.05) in development rate W) of free-living infective larvae was observed between different concentrations of nutrient broth (X) which was highest (20.6%1 in 0.12% nutrient broth concentrations, incubated at $20^{\circ}C$ for 5 days [Y = $-864.032X^2$ + 245.995X- 0.560 (r = 0.875)]. Yields (Y) of infective larvae were observed relatively high when the culture medium was incubated at higher temperatures (X) which peaked at $25^{\circ}C$ (20.0%) than at lower temperatures. $15^{\circ}C$M (10.9%) and $20^{\circ}C$ (18.1%) [Y = $-0.189X^2$ + 8.387x- 72.795 (r = 0.981)]. The period W) required for the development of infective larvae decreased with higher incubation temperatures (X) [Y = $0.035X^2$ - 2.025X + 32.375 (r = 0.995)] The highest yield (19.2%) of infective larvae was obtained from culture bag inoculated with 15.000 eggs than with below and over 15,000 eggs in 0.12% nutrient broth and incubated at $25^{\circ}C$ for 4 days. The newly adapted culture method (from egg to third-stage larva) may be useful as a bio-bar/bioassay system for screening new chemical products, anthelmintics and pesticides, as well as for parasito immunological studies with Strongwloides species.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.325-335
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• 1985

Biogas production from agricultural wastes were summarized as follows: 1. Biogas Generation Characteristics of Various Manures and Residues a. Gas yield from crop residues like rice straw, rice hull, corn stalk and coconut husk can be improved by addition of animal manures. b. Gas yield from coconut husk can be improved through aerobic fermentation for at least one week before loading in the digester. c. Gas yield from fresh rice straw is better than from pre-fermented one, whether alone or in combination with animal manures. d. Initial study has shown that fresh azolla can be substituted for animal manures in manurerice straw combinations and gas yield derived based on unit volatile solids loaded is actually better than for manure-residue combinations. e. Gas production is highly sensitive to substrate pH and becomes almost nil at a pH of below 6. 2. Effect of ambient conditions and other factors on biogas production in a house hold-size digester. a. Results showed that compaction of rice straw in straw-manure combination can reduce gas yield compared with loosely mixed straw. b. The effective gas production period extended to 70 days using freshly threshed rice straw and fresh cattle manure as feed material. c. Underground and above ground digesters with shade have relatively more stable substrate temperature than aboveground exposed digesters. This relative temperature instability may likely be the reason for lower gas yield for the exposed aboveground digester loaded with loose straw-cattle manure substrate, compared with the underground digester with the same substrate. 3. Economic Analysis a. Based on prevailing costs of fuel, materials, and labor in the Philippines, biogas produced from the household size system is cheaper than either LPG or kerosene. b. If other benefits like organic fertilizer, pollution control and convenience are considered, biogas will surely be the best alternative fuel source.

• Journal of Life Science
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• v.29 no.6
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• pp.679-687
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• 2019

Litsea populifolia, a plant species of the Lauraceae family, is widely distributed in the tropical and subtropical areas of Asia. The phylogenetic relationships and botanical characteristics of L. populifolia have been reported; however, its anti-oxidative and anti-cancer activities remain unclear. In this study, we evaluated the anti-oxidative and anti-cancer effects of ethanol extracts of L. populifolia (EELP) together with the molecular mechanism of its anti-cancer activity in human lung adenocarcinoma A549 cells. EELP showed significant anti-oxidative effects with a 50% inhibitory concentration at $11.71{\mu}g/ml$, which was measured by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. EELP exhibited cytotoxic activity and induced cell cycle arrest at the G1 phase in A549 cells in a dose-dependent manner, whereas EELP did not have the cytotoxic effect on the normal human lung cell line IMR90. Treatment with EELP also resulted in a decreased expression of G1/S transition-related molecules-including cyclin-dependent kinase (CDK) 2, CDK6, cyclin D1, and cyclin E-both for the transcription and translation levels. EELP-induced G1 arrest was associated with the phosphorylation of checkpoint kinase 2 (CHK2), p53, cell division cycle 25 homolog A (CDC25A), and the reduction of CDC25A expression in A549 cells. Collectively, these results suggest that EELP may exert an anti-cancer effect by cell cycle arrest at the G1 phase through both p53-dependent and p53-independent (ATM/CHK2/CDC25A/CDK2) pathways in A549 cells.

• Journal of agriculture & life science
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• v.51 no.4
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• pp.79-86
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• 2017

We performed simulations of shipping conditions to export 'Cheongdobansi' astringent persimmon to tropical regions. We stored the fruits at $0^{\circ}C$, $5^{\circ}C$, or $10^{\circ}C$ temperature for 15 days to simulate the transport conditions, and then maintained the fruits at $30^{\circ}C$ for 5 days to simulate the distribution condition. Variables that we focused on are 1) the transport temperature($0^{\circ}C$, $5^{\circ}C$, or $10^{\circ}C$) and 2) the treatment time of ethylene generator(before or after shipping). We examined the ripening ratio and quality of the fruits at the end of the shipping and at that of the distribution. The examination at the end of the shipping showed that all of the fruits were ripened at $10^{\circ}C$ transportation but not ripened at $0^{\circ}C$ or $5^{\circ}C$ transportation in the ethylene treated condition. The untreated fruits were not ripened regardless of the transportation temperature. The examination at the end of the distribution showed that all of the fruits were ripened at $5^{\circ}C$ and $10^{\circ}C$ transportation, while 38.5% of fruits were ripened at $0^{\circ}C$ transportation in the ethylene treated fruits before shipping. The fruits treated after shipping were 63.5% and 59.6% ripened at $0^{\circ}C$ and $5^{\circ}C$ transportation, respectively. Unexpectively, only 19.2 % of fruits treated after shipping ripened at $10^{\circ}C$ transportation.