• Proceedings of the Korean Society of Plant Pathology Conference
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• 1995.06b
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• pp.27-53
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• 1995

In plant pathology there is an increasing necessity for improved cytological techniques as basis for the localization of cellular substances within the dynamic fine structure of the host-(plant)-pathogen-interaction. Low temperature (LT) preparation techniques (shock freezing, freeze substitution, LT embedding) are now successfully applied in plant pathology. They are regarded as important tools to stabilize the dynamic plant-pathogen-interaction as it exists under physiological conditions. - The main advantage of LT techniques versus conventional chemical fixation is seen in the maintenance of the hydration shell of molecules and macromolecular structures. This results in an improved fine structural preservation and in a superior retention of the antigenicity of proteins. - A well defined ultrastructure of small, fungal organisms and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. From analyses of the compatible interaction between Erysiphe graminis f. sp. hordei on barley (Hordeum vulgare), various steps in the infection sequence can be identified. Infection sites of powdery mildew on primary leaves of barley are analysed with regard to the fine structural preservation of the haustoria. The presentation s focussed on the ultrastructure of the extrahaustorial matrix and the extrahaustorial membrane. - The integration of improved cellular preservation with a molecular analysis of the infected host cell is achieved by the application of secondary probing techniques, i.e. immunocytochemistry. Recent data on the characterization of freeze substituted powdery mildew and urst infected plant tissue by immunogold methodology are described with special emphasis on the localization of THRGP-like (threonine-hydrxyproline-rich glycoprotein) epitopes. Infection sites of powdery mildew on barley, stem rust as well as leaf rust (Puccinia recondita) on primary leaves of wheat were probed with a polyclonal antiserum to maize THRGP. Cross-reactivity with the anti-THRGP antiserum was observed over the extrahaustorial matrix of the both compatible and incompatible plant-pathogen interactions. The highly localized accumulation of THRGP-like epitopes at the extrahaustorial host-pathogen interface suggests the involvement of structural, interfacial proteins during the infection of monocotyledonous plants by obligate, biotrophic fungi.

• Journal of Embryo Transfer
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• v.28 no.2
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• pp.87-93
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• 2013

The efficiency of artificial insemination (AI) for horses remains unsatisfactory. It is mainly because each process of AI causes a detrimental effect on semen quality. To sustain quality of semen properly, several factors including libido of stallions and sperm damage during sperm processing and preservation should be considered. Stallions with decent libido produce a high ratio of sperm to seminal plasma in their ejaculates, which is the ideal semen composition for maintaining sperm quality. Thus, to maximize the fertility rate upon AI, stallions should be appropriately managed to enhance their libido. Seminal plasma should have a positive effect on horse fertility in the case of natural breeding, whereas the effects of seminal plasma on both sperm viability and quality in the context of AI remain controversial. Centrifugation of semen is performed during semen processing to remove seminal plasma and to isolate fine quality sperm from semen. However, the centrifugation process can also result in sperm loss and damage. To solve this problem, several different centrifugation techniques such as Cushion Fluid along with dual and single Androcoll-E$^{TM}$ were developed to minimize loss of sperm and to damage at the bottom of the pellet. Most recently, a new technique without centrifugation was developed with the purpose of separating sperm from semen. AI techniques have been advanced to deliver sperm to optimal region of female reproductive tract at perfect timing. Recombinant equine luteinizing hormone (reLH) and low dose insemination techniques have been developed to maximize both fertility rate and the efficiency of AI. Horse breeders should consider that the entire AI procedure should be optimized for each stallion due to variation in individual horses for a uniformed AI protocol.

• Reproductive and Developmental Biology
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• v.37 no.1
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• pp.9-16
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• 2013

Artificial insemination (AI) has been performed widely in swine industry using fresh liquid sperm instead of frozen type of sperm. However fresh sperm are not able to preserve more than three days with optimal motility and other sperm parameters for the successful fertilization, since in vitro stored sperm has an oxidative stress that resulted increase of abnormality and acrosome reation. To overcome these major problems, novel preservative formulation is needed to neutralize the oxidative stress and to provide suitable physiological environment for sperm in in vitro. In this study, naturally derived substances such as Poncirus trifoliate (Trifoliate orange), Garcinia mangostana (Mangosteen), pig placenta and testis extracts were tested as sperm preservative agents. Placenta extracts (PE), trifoliate orange extracts (TOE), testes extracts (TE) and mangosteen extracts (ME) were applied to analyze specific parameters for sperm motion characteristics individually and combinatorial. Each individual extract treatment can accelerate the sperm motility but noticeably TOE, TE and ME treatments exhibited the considerable and significant preservation of sperm motility. PE, TE and ME showed a significant (p<0.05) increase in ALH after one week. Further we evaluated the five different combinations of these extracts on sperm motility and its motion characteristics. Surprisingly even after one week ME, TOE and TE combination significantly preserved the sperm motility about 75%. It is noteworthy that unlike individual extract treatment, combination of ME, TOE and TE simultaneously protect the sperm motility and its motion characteristics. Taken together these data conclude that addition of ME, TOE and TE can be effective for preservation of pig sperm.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.57-57
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• 2001

This study was carried out to investigate the general characteristics such as volume, sperm concentration, sperm motility, sperm abnormality on whole semen, RSP-S and RSP-T semen and fractional semen of small size dogs, and the effect of temperature and preservation time and cryoproservation on motility of whole and RSP-S and RSP- T semen. Multiple ejaculates were collected from small dogs by the digital manipulation of penis. 1. The volume per ejaculate semen, sperm of concentration and motility and abnormal sperm rate of 1st fractional semen were 0.65±0.09㎖, 4.52±0.35×10/sup 6/ cells/㎖, 15.64±3.85% and 5.50±0.62%. Also, 2nd fractional semen were 1.25±0.20㎖, 3.35±0.48×10/sup 6/cells/㎖, 96.25±4.65% and 4.24±0.46%. And 3rd fractional semen were 1.45±0.21㎖, 3.85±0.52×10/sup 6/cell/㎖, 92.82±4.24% and 4.66±0.58%, respectively. 2. The sperm of concentration and motility and abnormal sperm rates of whole, RSP-S and RSP-T semen were 5.45±0.82×10/sup 6/ cells/㎖, 95.55±4.65%, 4.58±0.45% and 4.82±0.36×10/sup 6/cells/㎖, 90.10±3.42%, 6.48±0.68% and 4.55±0.45× 10/sup 6/cells/㎖, 93.25±3.85%, 4.82±0.58%, respectively. 3. The motility of whole, RSP-S and RSP-T semen were higher at 4℃ than at 38℃. When preservation temperature was at 4℃, survival rates of RSP-S and RSP-T sperm were 97.54%-6.25% at 1-72 hrs, 97.40%-5.62% at 1-100 hrs, respectively. 4. The survival rates of slow and rapid frozen 2nd fraction, RSP-S and RSP-T semen were 67.3±4.45%, 88.8±4.46% and 46.4±3.84%, 74.4±4.20%, respectively. Survival rates was significantly higher in frozen RSP-S and RSP-T semen than that in control group(8.5±2.12%).

• Food Science and Preservation
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• v.6 no.4
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• pp.411-416
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• 1999

This research was conducted to investigate changes in quality characteristics of gamma-irradiated chickens during storage at different temperature and periods. In heme pigment(myoglobin) content, metmyoglobin content of chicken stored at 5$^{\circ}C$ was not affected by gamma irradiation but slightly increased with the increase in storage period. All samples stored at -20$^{\circ}C$ were no different in heme pigment content between nonirradiated and irradiated samples and slightly decreased as the freezing storage period increased. The SDS electrophoresis patterns were not significantly different between nonirradiated and irradiated samples. All samples stored in at 5$^{\circ}C$ showed a prominent breakdown of molecular weights ranging from 97,000 to 116,000 Daltons after 8 weeks' storage. TBA values increased according to the increment of irradiation dose level and storage period at both temperatures, 5$^{\circ}C$and -20$^{\circ}C$. However, The acid value decreased with increasing irradiation dose level. In the VBN value, nonirradiated chickens were four times higher than that of 7 kGy-irradiated one.

• Parasites, Hosts and Diseases
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• v.32 no.1
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• pp.57-60
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• 1994

In order to search the fate of Thelohonellus kitauei spores the extrusion rates of the polar filaments were monitored in uipo chronologically. Preserved spores suspended with various solutions at $-70^{\circ}C$ showed almost the same vigorous pattern as early freezing stages up to 1,750 days after initial preservation. It revealed that the vlabllltles of some spores suspended with 0.45% and 0.9% NaCl solutions and distilled water at $5^{\circ}C$ continued for 1,628 days, 1,614 days and 1,721 days, respectively. And, the life spans of some spores in the previous solutions added with antibiotics at $5^{\circ}C$ were 1,628 days, 1,614 days and 1,714 days, respectively. Key words: TheLohanellus kitnuei, spore, extrusion rate of polar filament, life span

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1029-1034
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• 2001

The purpose of this research is to develop rapid setting cement latex modified concrete (RSLMC) which will be used to overlay bridge deck for maintaining and repairing. The main experimental variables were the types of rapid setting cement and variation of latex and antifoam agent contents were selected as admixture factor, then the properties of workability and strength development and durability properties were investigated. The results of this study show that latex content give increment of a slump due to surface tension in polymer particles and reduce unit weight of water for preservation of workability. In addition, When no and 1.6~3.2% antifoam agent were mixed, 8%, 2.0~3.8% were respectively obtained. An increasing the amount of latex produced concrete with increased flexural strength, but with slightly lower compressive strength. Rapid chloride permeability and freezing-thawing test carried out. As a results, according to increment of containing ratio antifoamer, strength of RSLMC increase, permeability showed lower value than ignorable 100 coulombs. Also, in the case of more than antifoamer 1.6%, the relativity dynamic modulus is mantained more than 90%, but in case of 0, 5%, it decrease. In consequence, with the view of strength and workability of RSLMC, it is considered that appropriate content ratio of antifoam agent and latex solid are respectively 1.6% by latex weight, 15% by cement weight.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.395-402
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• 2013

Sodium chloride is used to improve various properties of processed meat products, e.g., taste, preservation, water binding capacity, texture, meat batter viscosity, safety, and flavor; however, many studies have shown that sodium chloride increases the resistance of many foodborne pathogens to heat and acid. Listeria monocytogenes has been isolated from various readyto- eat (RTE) meat and dairy products formulated with sodium chloride; therefore, the objective of this paper was to review the effects of sodium chloride on the physiological characteristics of L. monocytogenes. The exposure of L. monocytogenes to sodium chloride may increase biofilm formation on foods or food contact surfaces, virulence gene transcription, invasion of Caco-2 cells, and bacteriocin production, depending on L. monocytogenes strain and serotype as well as sodium chloride concentration. When L. monocytogenes cells were exposed to sodium chloride, their resistance to UV-C irradiation and freezing temperatures increased, but sodium chloride had no effect on their resistance to gamma irradiation. The morphological properties of L. monocytogenes, especially cell elongation and filament formation, also change in response to sodium chloride. These findings indicate that sodium chloride affects various physiological responses of L. monocytogenes and thus, the effect of sodium chloride on L. monocytogenes in RTE meat and dairy products needs to be considered with respect to food safety. Moreover, further studies of microbial risk assessment should be conducted to suggest an appropriate sodium chloride concentration in animal origin foods.

• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.95-99
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• 1972

Studies were made to investigate the influence of vacuum packing after irradiating mean doses of gamma ray at freezing temperature $(-20^{\circ}C)$ on the keeping quality and color of raw beef. Fresh round steaks were packaged anaerobically in aluminum foil, and irradiated with 0.25 and 0.5 Mrad followed by storage at $5^{\circ}C$. The shelf life of beef irradiated with 0.5 Mrad could be extended about 10 days longer than unirradiated, and the off-odors was not developed. The discoloration by irradiation was shown, but soon reverted to about 90 percentage myoglobin in 20 hours.

• Korean Journal of Poultry Science
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• v.41 no.1
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• pp.21-27
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• 2014

To preserve chicken genetic materials like cryopreserved spermatozoa, various kinds of freezing agents like glycerol, dimethylsuloxide, dimethylformamide or dimethylacetamide have been used for rooster semen preparation. Recently, the usage of N-methylacetamide (MA) for Ogye rooster semen preservation resulted in hatched chicken successfully. In this study, we investigated the effects of 7, 9 and 11% of MA on the viability, fertility and hatchability of frozen-thawed rooster semen using artificial insemination. The results of viability, fertility and hatchability in frozen semen with 7%, 9% or 11% MA were $35.16{\pm}6.12%$, $67.83{\pm}15.3%$ and $66.2{\pm}16.3%$ of motile sperm rate, 21.5%, 34.7% and 25% of fertility rate, and 100%, 89.5% and 87.5% of hatchability rate. The results of control group with frozen semen were 96.0% of fertility rate and 92.2% of hatchability rate. With these results, the concentration range of MA as a freezing agent of rooster semen could be 7~9% of media. The higher concentration of 9 % MA could decrease the fertility rate of thawed semen not the rate of hatchability rate. So the use of MA without affecting fertility rate would be a key point of freezing method of rooster semen for poultry genetic resource preservation.