• Korean Journal of Plant Tissue Culture
• /
• v.27 no.3
• /
• pp.185-189
• /
• 2000

For the micropropagation, node explants of cassava were cultured in liquid MS medium with various concentrations of cytokinins on a rotary shaker (100 rpm) for 2 weeks. The adventitious roots and shoots from the explants were differentiated more efficiently in liquid medium than in solid. But root formation was not inhibited in medium with BAP and kinetin at low concentration (＞0.05 mg 1/sup -1/), while in medium added with BAP and zeatin at high level (＜0.25 mg 1/sup -1/), it was inhibited by callus forming on cut end of the cuttings. However, all of plantlets grown in liquid medium for more than 2 weeks showed symptoms of hyperhydricity. The plantlets grown in liquid medium were transferred into culture bottles filled with fine sand or artificial soil (pitmoss：perlite：vermiculite, 1：1：1 v/v) wetted with half strength of Knop's solution. After transplanted to culture bottles, some of vitriscent leaves were defoliated and new leaves were normally formed from shoot apex. Most of plantlets (＞95%) were hardened-off successfully only in culture bottles with fine sand, and grew into 3-5 cm seedlings possessing 4-6 nodes after 4 weeks. Thus, the mass propagation of cassava on medium containing cytokinin could be established based on the suspension culture using node explants.

• Korean Journal of Plant Tissue Culture
• /
• v.27 no.3
• /
• pp.213-217
• /
• 2000

To investigate the cucumber regeneration from embryogenic calli, shoot tips of aseptically-grown cucumber seedlings were used as explants for establishing tissue cultures. Growth and differentiation of callus were studied by using Murashige and Skoog's (MS) medium containing 0.5 to 2 mg/L 2,4-D. Plantlets were induced from shoot tip culture on the plant growth regulators-free MS medium. Non-embryogenic calli and viscous calli were induced on the medium supplemented with 0.5 to 2 mg/L 2,4-D, but embryogenic callus was not induced on the same medium. Segments (ca. 5∼10 mm) of aseptically-grown hypocotyl from five to seven days old seedlings after germination were placed on MS medium supplemented with 1 mg/L 2,4-D for 50 days. Embryogenic calli and embryoids were induced only from the seedlings grown in dark condition, and hypocotyl was placed on the media explanted in light condition. Foully-five point one percent of white fragile calli and 0.6% yellowish compact calli formed roots. Yellowish callus lines were investigated to have a considerably higher concentration of crude proteins than white callus lines. Plantlets derived from embryogenic calli or embryoids have been transferred to pots containing sterile vermiculite and perlite. Normal fruits were harvested from nutrient culture on aggregated hydroponics in the F-clean house.

• Food Science of Animal Resources
• /
• v.29 no.6
• /
• pp.695-701
• /
• 2009

This study was performed to evaluate the effectiveness of biological critical control points using the genetic profile of Escherichia coli isolates from pork cutting plants. Samples were collected from carcasses, equipment (knife, table, glove, transport belt, boning and skinning machine), the environment (wall and floor), and meat cuts during the cutting process from two plants. Pulsed-field gel electrophoresis (PFGE) was used to characterize the E. coli isolates. An identical genotype was detected from the carcasses, equipment, environment, and final meat cuts, and showed that the incoming carcasses, which were contaminated during transportation from slaughterhouses, were a major source of E. coli that was spread throughout processing. Also, consistent cross-contamination due to improper cleaning and disinfection procedures was another possibility. As a result, incoming carcasses and cleaning procedures should be considered critical control points in pork cutting plants, since a heating step is not used to inactivate microorganisms. Furthermore, the high rate (59.6%) of E. coli isolation indicates E. coli can be a good indicator in livestock processing plants even though it has genetic diversity.

• Journal of Korean Society of Forest Science
• /
• v.73 no.1
• /
• pp.33-42
• /
• 1986

This study was carried out to investigate the optimum conditions for isolation and culture of mesophyll protoplasts from Populus alba ${\times}$ P. glandulosa. The results obtained from the experiments are as follows; 1) The suitable concentration of BAP for shoot multiplication was 0.4 mg/l. 2) High yield and viability of isolated protoplasts were obtained by our high enzyme-short time incubation method. 3) Optimum enzyme concentrations for mesophyll protoplast isolation were Cellulase 2%, Macerozyme 0.8%, Hemicellulase 1.2%, Driselase 2%, and Pectolyase Y-23 0.05%. 4) 0.6M mannitol in enzyme solution was the most effective for protoplast isolation and viability. 5) The most adequate pH level of enzyme solution was pH 5.6. 6) The effect of DTT and MES buffer was significant. 7) For protoplast purification, 0.6M sucrose was the most proper concentration. 8) The adding effect of Dextran T40 in floating solution was important. 9) The mesophyll protoplasts isolated through our high enzyme-short time incubation method revealed successful response to culture condition over 3 weeks of culture.

• FLOWER RESEARCH JOURNAL
• /
• v.18 no.1
• /
• pp.9-14
• /
• 2010

This study was conducted to examine the effects of IAA and kinetin on induction of gemmae and gametophytes in Hypnum plumaeforme moss during tissue culture. Explants were obtained from sterilized gametophyte tips cultured on solid basal medium containing Knop's major salts and Nitsch and Nitsch's trace elements. After culture, inoculated gametophyte tip produced protonema firstly, changed to new gametophytes after four weeks. Aseptic gametophytes were chopped and inoculated on the same media containing 0.01, 0.1, 1 and $10{\mu}M$ of IAA and kinetin. As a result, secondary protonemata as well as protonemal gemmae were formed from gametophytes. But protonemal gemmae formation was varied according to the concentration of IAA and kinetin. Lower concentration of IAA and kinetin promoted gemma formation and bud induction. Especially, $0.01{\mu}M$ of kinetin showed the highest frequency of bud and gemma production. All the materials, obtained from $0.01{\mu}M$ kinetin medium, were subcultured to media supplemented with 0.01, 0.1, 1 and $10{\mu}M$ of IAA and kinetin again to induce gametophytes. After subculture, protonema and calli were developed from secondary protonema, and induced gametophytes finally. IAA regulated induction and growth of gametophytes, and kinetin influenced gemma formation and gametophyte induction also. All aspects of development of this moss species were governed by the external growth regulators.

• Journal of agriculture & life science
• /
• v.44 no.6
• /
• pp.147-157
• /
• 2010

This study was carried out to develop the normal temperature-circulatable retort sterilized imitation crab leg (RSIC) with long shelf-life by retort sterilization. We have examined the optimum retort sterilization conditions and quality characteristics of the RSIC. Central composite design for response surface methodology (RSM) was adopted for optimization of retort sterilization, and experimental central composite design consisted of 11 samples such as 4 factorial points; 4 star points; 3 central points. Sterilization temperature and $F_0-value$ for retort sterilization were chosen for independent variables, and shearing force, whiteness and sensory score about texture were selected as a dependent variable. As a results of RSM analysis, multiple response optimization for the RSIC by Minitap statistical programing was $F_0-value$ 3.3 min. at $117.5{^{\circ}C}$. Also RSM analysis indicated such as sterilization temperature during retort sterilization was the most influential factor, while $F_0-value$ little affected on quality of the RSIC.

• Journal of the Korean Child Neurology Society
• /
• v.26 no.4
• /
• pp.246-250
• /
• 2018

Purpose: Meningitis is an acute childhood infection caused by viral or bacterial infection. The purpose of the present study is to analyze the differences between enteroviral meningitis and non-enteroviral aseptic meningitis. Methods: From January 2013 to December 2016, we retrospectively reviewed the medical records of a total of 303 aseptic meningitis patients who visited Wonju Severance Christian Hospital. We examined demographics of all patients and analyzed serologic and cerebrospinal fluid tests, clinical symptoms, and outcomes. Results: Of a total of 303 patients, 197(65.0%) were male, and the most cases occurred from June to November (91.8%). The most common pathogen of meningitis was found to be enterovirus (65.0%). According to the etiology, the enteroviral meningitis group had significantly more headache and enteric symptoms (P=0.0003 and P=0.0013, respectively). Furthermore, the non-enteroviral meningitis group showed pleocytosis in the cerebrospinal fluid and a significantly higher rate of seizure at 1 to 4 years (P=0.0360 and P=0.0002, respectively). Conclusion: In this study, enteroviral meningitis was the most common and the prognosis was good. When compared between two groups, neurological symptoms were frequent in patients with non-enteroviral meningitis in groups 1 to 4 years.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.2
• /
• pp.681-693
• /
• 2019

Multi-use ophthalmic solutions are used many times after opening; therefore, there is a high possibility of decreased quality during use. This study was conducted to determine the recommended use period of multi-use ophthalmic solutions based on evaluation of the stability by comparing stability evaluation regulations of the USA, EU and Korea We selected four types of multi-use ophthalmic solutions (Olopatadine (Olo), Fluorometholone (Flu), Dorzolamide (Dor), Timolol (Timol)) that are frequently marketed in Korea and evaluated their stability during storage according to the actual usage method after opening. The Olo had a decrease in assay and preservative content at 2 months after opening, while Flu showed a significant difference from day 28 after opening. For Dor, significant differences were observed from day 14 after opening in the assay and impurity test item and Timol showed a significant difference from day 28 after opening. Based on the results of the stability test Olo and Flu should only be used within 28 days of opening, while Dor and Timol should be used within 14 days of opening. Therefore, we suggest that regulations system related use periods of multi-use ophthalmic solutions designed as aseptic preparations should be improved based on the results of stability tests after opening.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
• /
• v.61 no.11
• /
• pp.580-587
• /
• 2018

Background and Objectives We evaluated the clinical characteristics and vestibular function of patients with direction changing vibration induced nystagmus (DC VIN) and unilateral vestibular hypofunction and suggest clinical implication and a proposed mechanism of DC VIN. Subjects and Method The records of 315 patients who underwent the VIN test were reviewed retrospectively. Among these, 18 patients (5.7%) showed DC VIN, and out of whom, 15 patients (4.8%) were diagnosed as unilateral vestibular hypofunction by caloric, rotation chair (RCT), and video head impulse test (vHIT). We analyzed the relationship between DC VIN and the dizziness characteristics, duration of disease, and the outcome of the vestibular function test. Results The mean age of 15 patients was $67.4{\pm}10.7years$ and the mean duration of dizziness was $13.6{\pm}29.7months$. The caloric test revealed 25% of the patients to have significant canal paresis [Caloric vestibular neuritis (VN)], while 75% showed normal caloric response. However, unilateral vestibular hypofunction was observed by abnormal results in RCT or vHIT (Non-caloric VN). Seven patients showed ipsilateral DC VIN (nystagmus to vibrated side) and eight patients contralateral DC VIN (nystagmus to opposite side of vibration). Patients with ipsilateral DC VIN were shown to have a significant longer duration of dizziness than those with contralateral DC VIN. Conclusion Although rare, DC VIN can also be found in patients with unilateral vestibular hypofunction. Patients with DC VIN had a mild vestibular asymmetry with Non-caloric VN or Caloric VN in the process of compensation. The mechanism of ipsilateral DC VIN seems to be due to the small amount of vestibular asymmetry, which is smaller than the interaural attenuation of vibration.

• Research in Plant Disease
• /
• v.29 no.1
• /
• pp.45-51
• /
• 2023

The study was conducted to investigate the infestation and distribution of plant-parasitic nematodes on kiwi orchards in Korea. Plant parasitic nematodes genus and densities were investigated at a total of 102 sites in Jeollanam-do, Gyeongsangnam-do, and Jeju-do, which are the main production areas of domestic kiwi orchards. Plant parasitic nematodes detected were of 9 genera, including root-knot nematodes (Meloidogyne spp.), spiral nematodes (Helicotylenchus spp.), and needle nematodes (Paratylenchus spp.), and 56% of the 102 plantations were infected with root-knot nematodes. Root-knot nematodes were found to be the most important plant parasitic nematode in domestic kiwi orchards. The average density of root-knot nematodes is 97 per 300 cm³ soil, and there is concern about the kiwi yield reduction. As a result of identifying the root-knot nematode species: M. arenaria, M. hapla, M. incognita, and M. javanica. Among them, M. arenaria is the most dominant. As the plant parasitic nematode infection route in fruit trees is often spread through the transplantation of infected seedlings, attention should be paid to the production of nematode-free plants during the production and supply of kiwifruit plants.