The effects of isotonic saline on corneal penetration, thickness, and injury, as well as lacrimal secretion in a rat model of dry eye were investigated, in comparison with distilled water. Male Sprague-Dawley rats received intraperitoneal administration of atropine sulfate (20 mg/kg) and their eyes were exposed to dry (relative humidity 25-35%) air flow (2.4 m/sec), under Zoletil anesthesia, for 5 hr to induce dry eye. During the period of dry eye induction, distilled water or isotonic saline (5 μl) was instillated onto the cornea every 30 min. Corneal penetration was measured through fluorescein dye quantification, and corneal thickness and injury were examined under a microscope. Lacrimal (tear) secretion and mucin-like glyocoprotein excretion from goblet cells were measured using the Schirmer test and microscopy, respectively. In dry eye rats treated with distilled water, corneal thickness, tear secretion, and mucin-like glycoprotein excretion were decreased to 74.0%, 74.1%, and 46.3% of normal levels, respectively, resulting in marked corneal injury and a significant increase in corneal penetration. In comparison, treatment with isotonic saline resulted in recovery of lacrimal secretion, in spite of a slight improvement of mucin-like glycoprotein excretion, and thereby prevented corneal penetration of fluorescein by 10%. The results indicate that repeated instillation of isotonic saline could provide slightly greater protection from corneal injury, compared with distilled water by facilitating lacrimal secretion, in addition to relief of inconvenience and pain.
[Introduction] Mushroom constituents have been found to be highly effective in the prevention and treatment of lifestyle diseases such as lipidosis, high blood pressure, and diabetes, which are closely linked to eating habits, and several varieties of functional foods have been developed from these constituents. As a result, doctors of Western medicine in particular, who in the past have been dismissive of herbal or Oriental medicine, are now tending to take a more proactive stance toward adopting the better aspects of alternative, complementary or traditional medicine. Natural remedies and folk medicines have been incorporated into the treatment of cancer, for example, and in the same way it has become common to incorporate mushrooms into treatment regimes before and after surgical interventions and alongside therapies such as chemotherapy, radiation therapy, and hormone therapy. Mushroom chitosan, which is investigated in this study, is a novel functional ingredient made from the mushroom Flammulina velutipes (Curt.:Fr.) Sing., which is the most common edible mushroom to be artificially cultivated in Japan and has long been part of the Japanese diet. Unlike chitosans of crustacean origin, mushroom chitosan is rich in the main structural component β-glucan, and this dietary fiber is expected to have positive functions within the body. In particular, there are hopes that mushroom chitosan will inhibit cholesterol and fat absorption in the small intestine, and suppress total cholesterol and neutral fat levels in the serum. Previous human trials have confirmed the anti-metabolic syndrome efficacy of supplements containing mushroom chitosan. Here we report the ameliorative effects of mushroom chitosan in an animal model of genetic obesity and lipidosis. [Methods] Mushroom chitosan (RSK2, Ricom Corporation) was administered at different doses to Crj:(ZUC)-fa/fa rats an animal model of obesity and hyperlipidemia continuously for 10 weeks. The rats were kept at a temperature of 22±1ºC and humidity of 60±10%, and illuminated with fluorescent lamps for 12 h/day (07:00~19:00). Body weight, food consumption, body condition, and hematological and blood biochemical blood parameters were measured, and pathological examination (pathological analysis of hepatic lipid droplets) was performed using HE staining. [Results and discussion] Mushroom chitosan (RSK2) showed high efficacy in suppressing weight gain in Crj:(ZUC)-fa/fa rats presenting obesity due to genetic lipidosis. The smallest effective dose was 3 mg/kg. In addition, values for neutral fat, β-lipoproteins and total lipid due to ingestion improved to the normal values. Moreover, the pathological study of the liver revealed a decrease in lipid droplets appearing in the central zone of the hepatic lobule and a decrease in fat deposition in the liver in the group that ingested mushroom chitosan. The results also suggested that serum lipid levels were improved through egestion of excess fat with the feces. Mushroom chitosan (RSK2) was shown to be effective in controlling increase in serum lipids as it has lipase-inhibiting activity, and was shown to control fat deposition in internal organs through egestion of excess blood lipids with the feces. Mushroom chitosan is thus a functional food that is effective in preventing and treating contemporary lifestyle diseases.
Influenza virus infection is a zoonosis that results in high mortality in animals and humans. Several recent avian influenza outbreaks have posed a significant public health threat to humans because there have been many cases of direct interspecies transmission from birds to humans. Influenza virus infection causes acute respiratory failure, which is the main cause of death, while chronic influenza virus infection in the central nervous system results in neural dysfunction. Of particular interest, according to one report, a group of patients who recovered from influenza virus infection during pandemics showed neuropsychiatric disorders, including depression, schizophrenia, and Parkinsonism. Thus, study of the etiology of neuropsychiatric disorders caused by influenza virus infection is needed. In order to conduct necessary experiments, it is essential to reproduce neurological phenomena that are manifested by human patients who have recovered from influenza virus infection using laboratory animals. In this review, we will discuss some of the facts that should be considered when establishing an animal model for study of central nervous system responses to influenza virus infection using mice.
[Introduction] Matsutake mushroom (Tricholoma matsutake), an ectomycorrhizal fungus has low activity for polysaccharide hydrolyzing enzymes such as amylase, cellulase and hemicellulase. Therefore, only glucose and a few other monoand di-saccharides can be used to grow this fungus. Then, we examined the possibility for the mass production of the mycelia using the saccharified rice bran as growth substrate. [Methods and Results] For the selection of Kouji-mold, 32 strains of Aspergillus spp. were tested. These fungi were cultivated in potato dextrose liquid (PDL) medium added rice bran and amylase activities were assayed. As a result, Kouji-mold from Isesou Mugi Kouji (Asp. oryzae) was selected to use for saccharification of rice bran. When the saccharified rice bran was used as the growth substrate, the mycelical growth was enhanced. In this mushroom, the dry weight mycelia increased at about 3.0 times (control : 50mg, saccharified rice bran : 160mg, 60days, 24℃) by using saccharified rice bran compared with that of the control without saccharified rice bran. From there results, we see that saccharified rice bran is a useful culture material for the mass production of matsutake mycelia. Chemical analysis in saccharified rice bran solution was done with TLC and HPLC. The large amounts of glucose and maltose were detected in the saccharified solution. Now, we are trying to hydrolyze of cellulose and hemicelluloses components in rice bran using Asp. kawachii or Asp. saitoi isolated from Shouchu kouji.
We develop a proto-model of an off-axis reflective telescope for infrared wide-field observations based on the design of Schwarzschild-Chang type telescope. With only two mirrors, this design achieves an entrance pupil diameter of 50 mm and an effective focal length of 100 mm. We can apply this design to a mid-infrared telescope with a field of view of 8 ̊ X 8 ̊. In spite of the substantial advantages of off-axis telescopes in the infrared compared to refractive or on-axis reflective telescopes, it is known to be difficult to align the mirrors in off-axis systems because of their asymmetric structures. Off-axis mirrors of our telescope are manufactured at the Korea Basic Science Institute (KBSI). We analyze the fabricated mirror surfaces by fitting polynomial functions to the measured data. We accomplish alignment of this two-mirror off-axis system using a ray tracing method. A simple imaging test is performed to compare a pinhole image with a simulated prediction.
Titanium dioxide (), which is one of the most basic materials in our daily life, plays a key role for environment purification. We synthesized nanoparticles by the hydrolysis reactions of titanium tetraisopropoxide using as a peptizing agent or as a chelating agent in the sol-gel method. The powder consisted of a rod shape or a spherical shape according to the concentration and kind of acid. The physical properties of nanoparticles were investigated with X-ray diffraction, SEM, BET analysis, and UV-Vis spectrophotometer.
The diapause duration P. ussuriensis eggs is known to either one year or prolonged to additional years. This complex life cycle is mainly caused by the interruption at two embryonic stages: early stage (initial diapause) and fully developed late stage (final diapause). The environmental cues, such as temperature, is critical to determine the diapause duration but the precise diapause mechanism of P. ussuriensis eggs is unclear. We demonstrated temperature effects on the entrance of initial diapause. Newly oviposited eggs were incubated at two temperature conditions (20℃and 30℃) for 60 days. When eggs were incubated at 20℃, egg weights were not significantly changed, but at 30℃ those were gradually increased to 1.5 times for 50 days. Genomic DNA contents of eggs were similarly increased at 30℃. Total RNA contents at 30℃ were highly increased from the 15-days-old but not at 20℃. In addition, we further analysed expression levels of two heat shock protein 70 (hsp70a, hap70b) genes during embryonic development. Our results suggest that initial diapause occurred between 10 and 15 days after oviposition and its entrance was blocked by high temperature incubation.
Spider mites are one of major pests in cultivations of various ornamental plants and also important in plant quarantine service. Due to the very small body size and high similarity within the Genus the identification of species is difficult even at the microscopic observation. To identify 5 major species (Tetranychus cinnabarinus, T. urticae, T. phaselus, T. kanzawai and T. truncatus) in the Genus Tetranychus at the molecular level, we designed 4 species-specific primer sets using nucleotide sequences of the internal transcribed spacer (ITS2) region in the nuclear ribosomal repeat unit. At the PCR diagnosis of extracted genomic DNAs of 5 species using each primer set, specific primers of both T. phaselus and T. truncates were species-specific to their own species samples. However, specific primer set of T. urticae detected T. cinnabarinus as well as T. urticae. Specific primer set of T. kanzawai detected T. truncates as well as T. kanzawai, even though detection intensities were lower in non-target species.
Due to the very small body size of spider mite, it is difficult to prepare DNA extraction simultaneously with slide samples from a single individual. Here we developed non-mashed DNA extraction method from a single spider mite to apply for molecular as well as morphological identification. Total genomic DNA was isolated from a single female adult using Genomic DNA extraction kit without the sample homogenization. DNA content of a single spider mite was 60-90 ng, which is sufficient for the PCR analysis. However, the quantity of extracted DNA and quality of the cuticle sample were dependent on the incubation time into the lysis buffer. Our results suggest that non-mashed DNA extraction method would be useful for the identification of very small mites as well as insects at the levels of DNA and morphology.
This study was conducted in order to investigate repeated-dose toxicities of Magnolia ovobata ethanol extract (MEE). MEE was administered orally to male and female Sprague Dawley rats at dose levels of 0, 500, 1,000, or 2,000 mg/kg for four weeks. Repeated administration of MEE did not induce abnormalities in general signs, body weight gain, feed and water consumption, necropsy findings, or organ weights. In addition, no abnormality was observed in hematological analyses; red blood cells and their indices, white blood cells, platelets, and coagulation times. In male rats, BUN and creatinine showed an increase at doses of 2,000 mg/kg and 500-1,000 mg/kg, respectively, while in female rats, lactate dehydrogenase and creatine phosphokinase showed a decrease at 2,000 mg/kg, the upper-limit dose of repeated-dose toxicity studies. However, there were no dose-dependent increases or gender-relationship. In addition, other parameters of the hepatic and muscular toxicities as well as energy and lipid metabolism were not affected. In microscopic examination, no considerable pathological findings were observed. The results indicate the safety of oral administration of MEE to the upper-limit dose.
The epidemiology of reported food-borne disease (FBD) outbreaks from 2001 to 2008 in Korea and Japan were compared in this study. The outbreak rate of FBD in Japan was significantly higher although the average number of patient in each outbreak in Korea was much higher. In both countries, summer was the season when most FBD outbreaks occurred. The comparison study revealed that FBD outbreaks in spring were more frequent in Korea, and outbreaks in winter were more frequent in Japan. Almost half of FBD outbreaks were observed at restaurants in both countries while FBD outbreaks at schools and work-places in Korea were much higher than in Japan. The most frequent cause of bacterial FBDs in Korea was pathogenic Escherichia coli followed by Salmonella species. On the other hand, Campylobacter jejuni was the most frequent source of bacterial FBDs in Japan. Norovirus, which is related to uncontrolled hand hygiene and involvement of ill food workers, was the main cause of viral FBDs in both countries. In conclusion, there are common epidemiological characteristics as well as several differences in FBD outbreaks of Korea and Japan. These are suggested to be originated from the characteristic of climate, food sources, and life styles in two countries. Establishment of stricter control and surveillance system for FBD outbreaks are required for prevention and reduction of FBD outbreaks in both countries.
This study analyzes a nationwide English placement test in the Rasch framework Data were obtained from 297 first-year junior high school students. The assessed person (.75) and item reliability (.95) indicate that the test was fairly consistent and reproducible with other samples of examinees. About 60% of total variation was explained under the assumption of unidimensionality. The person separation index suggests that two and a half ability levels can be differentiated by means of the test. Overall, the ability distribution of students was higher than the difficulty distribution of items. The fìt statistics identified a few misfìt items, but their impact on the utility of the test appears nonsignificant.
Insect pest monitoring program in subsistence warehouses can detect pest problems in early infestation stages. Temporal and spatial distributions of pests produced by monitoring allows facility managers and pest control operators to visualize pest problems and evaluate effectiveness of cleaning, sanitation and pest management practices. Pheromone-based insect monitoring traps were placed to study temporal and spatial distribution of Lepidopteran and Coleopteran stored product pests in two central distribution centers of United States Military Forces in the Republic of Korea, from March to December 2008. The two distribution centers receive store and issue subsistence and they are located in two different cities, Seoul and Taegu. As a result, three pests, Plodia inter punctella Hübner (Indian meal moth), Lasioderma serricorne F. (cigarette beetle), and Trogoderma variabile Ballion (warehouse beetle), were detected on the traps. P. interpunctella was most abundant, followed by L. serricorne and T. variabile. Different phenologies and spatial distribution of each species were seen from the two warehouses, that were related with internal temperature of the two warehouses and food availability. The program benefited to lead a better understandings for existence and extent of local pest problems in the two subsistence distribution centers, and also helped to find effective pest management periods and locations.
Developmental time, mummification, pupal mortality, sex ratio of a South Korean strain of Aphelinus varipes Förster parasitizing the green peach aphid, Myzus persicae were studied at 20, 25 and 30℃ in controlled climate cabinets. Plastic container with sweet pepper(Capsicum annuum L.) were used as experimental units. Green peach aphid in different larval instars and as adults, reared at the three different temperatures, were presented to A. varipes in a 'no-choice' and 'choice' situation for 6h. These presentations were done at 25℃ in each experiment to avoid an influence of temperature on parasitization rate. In case of no-choice test, more 1st(24%), 2nd(22%) and 3rd(38%) instar aphids were parasitized than 4th(14%) instar and adult(10%) among the aphids reared at 25℃. In case of choice test, more 1st(41%), 2nd(42%) and 3rd(29%) instar aphids were parasitized than 4th(13%) instar and adult(0%) among the aphids reared at 25℃. Pupal mortality of the parasitoid was not influenced by temperatures. The sex ratio of A. varipes was male-biased, and varied between 49.4% females developed from aphids reared at 30℃ and 42.8% from aphids reared at 20℃. The sex ratio was not significantly influenced by host stages. The developmental time of A. varipes parasitizing the green peach aphid ranged from 26.1days at 20℃ to 11.1days at 30℃.