Maca has been reported to alleviate male menopause symptoms in humans and experimental animals; however, its mechanism of action in improving male menopause has not been clearly identified. This study aimed to investigate the mechanism of action of gelatinized maca in improving male menopause by analyzing serum testosterone, testicular androgen receptor (AR) expression, and testicular oxidation-antioxidation balance. Gelatinized maca was administered orally to aged male C57BL/6 mice at three doses (500, 1,000, and 1,500 mg/kg/day) for 28 consecutive days. Serum biochemical analysis showed an increase in serum hydroxysteroid 17-beta-dehydrogenase 13 (HSD17β13) concentration at 1,500 mg/kg/day and a decrease in serum sex hormone-binding globulin (SHBG) concentration at ≥ 1,000 mg/kg/day. Gelatinized maca administration also resulted in the increased expression levels of testicular AR and cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) at 1,500 mg/kg/day. Oxidative stress analysis showed an increase in testicular superoxide dismutase and glutathione reductase activities and a decrease in testicular malondialdehyde at 1,500 mg/kg/day. In conclusion, gelatinized maca administration to aged male mice increased HSD17β13, AR and CREB expression, and antioxidant capacity and decreased serum SHBG. The results of the present study suggest that gelatinized maca may be a useful substance that can help alleviate male menopause symptoms.
2017년 경북지역은 약 700ha 이상의 면적에서 미국선녀벌레의 피해를 입었다. 그 중 600ha의 피해면적이 떫은감 주요 생산지인 청도군에서 발생하였다. 미국선녀벌레의 효율적인 방제를 위해 2018년 5월 상순에 침투이행성 약제를 토양에 처리하여 약충이 부화하기 전감나무 수체 내 약제를 이행시켜 방제효과를 조사하였다. 토양입제처리의 방제효과 조사를 위하여 토양입제 단독처리(5월 상순), 경엽살포 단독처리(6월 중순), 토양입제(5월 상순) 및 경엽살포(6월 중순) 체계처리를 비교하였다. 조사결과 토양입제 단독처리 시 약제처리 후 약 70일 이상 90%이상의 방제효과가 지속되었고, 경엽살포 단독처리 시 약제처리 후 약 2주 동안 90%이상의 방제효과를 보인 뒤 방제효과가 감소하였다. 또한 토양입제 및 경엽살포 체계처리 시 약제처리 후 약 70일 동안 95%이상의 높은 방제효과를 보였다.
국내 판매되고 있는 사슴벌레종[넓적사슴벌레(Dorcus titanus), 참넓적사슴벌레(Serrognathus consentaneus), 남방넓적사슴벌레(D. titanus jejuensis, 가칭), 애사슴벌레(D. rectus) 및 왕사슴벌레(D. hopei)]과 부산 지역에서 채집한 넓적사슴벌레 12개체와 경남 의령군에서 채집한 1개체의 미토콘드리아 DNA 중 cytochrome oxidase I(COI) 를 이용하여 계통을 비교분석하였다. 아울러 NCBI에 기등록된 북한, 일본, 대만, 필리핀, 인도네시아 및 태국의 넓적사슴벌레의 COI 서열을 이용하여 추가 분석하였다. 먼저 판매되고 있는 사슴벌레종은 넓적사슴벌레, 남방넓적사슴벌레 및 참넓적사슴벌레의 group I과 애사슴벌레 및 왕사슴벌레의 group II로 구분되었다. 부산지역 및 의령에서 채집한 넓적사슴벌레의 경우 COI 및 COII로 분석 결과 북한에서 기보고 된 3개체를 포함해 유전적 변이에 있어 큰 차이가 나타내지 않았다. 또한 한반도와 일본 일부지역에서 높은 상동성을 확인하였는데 그 외 아시아 지역에 서식하는 넓적사슴벌레와는 다른 그룹을 형성함을 확인하였다. 이러한 결과들은 국내 서식 사슴벌레 종의 유전적 분석과 함께 외래 유입종을 판별하는 근거자료로 활용될 수 있을 것이다.
Fe-6.5 wt.% Si alloys are widely known to have excellent soft magnetic properties such as high magnetic flux density, low coercivity, and low core loss at high frequency. In this work, disc-shaped preforms are prepared by spark plasma sintering at 1223 K after inert gas atomization of Fe-6.5 wt.% Si powders. Fe-6.5 wt.% Si sheets are rolled by a powder hot-rolling process without cracking, and their microstructure and soft magnetic properties are investigated. The microstructure and magnetic properties (saturation magnetization and core loss) of the hot-rolled Fe-6.5 wt.% Si sheets are examined by scanning electron microscopy, electron backscatter diffraction, vibration sample magnetometry, and AC B–H analysis. The Fe-6.5 wt.% Si sheet rolled at a total reduction ratio of 80% exhibits good soft magnetic properties such as a saturation magnetization of 1.74 T and core loss (W5/1000) of 30.7 W/kg. This result is caused by an increase in the electrical resistivity resulting from an increased particle boundary density and the oxide layers between the primary particle boundaries.
There are over 3,000 different species of mosquitoes throughout the world; currently 56 species are reported in Korea. Mosquitoes can act as vectors for many disease-causing viruses and parasites during blood sucking. Various species of mosquitoes are estimated to transmit various types of disease to more than 700 million people annually in Africa, South America, Central America, Mexico, Russia, and much of Asia, with millions of resultant deaths. At least two million people annually die of these diseases, and the morbidity rates are many times higher still. To prevent the spread of diseases, KNIH (Korea National Institute of Health) used three categorized methods; identifying or taxonomic analysis of mosquitoes, detecting virus caring mosquitoes, and detecting malaria from Anopheline mosquitoes. We have proved that taxonomic analysis using DNA barcording method (COI gene) is useful to complement identification of mosquito species. In detecting virus, we have reported Cx. orientalis as a new potential Japanese encephalitis virus (JEV) vector. We also reported that the Anopheline mosquito species composition and Plasmodium vivax infection rates in malaria hot spot in Korea.
Aedes albopicuts, known as asian tiger mosquito or forest mosquito, is characterized by its black and white strips on legs and body. Ae. albopictus is an important vector mosquito for the transmission of many viral pathogens such as dengue fever and chikungunya fever. Unlike other mosquito, Ae. albopictus attacks people mainly during the daytime in the forest. To evaluate the diel activity of Ae. albopictus, three times mosquito collecting were conducted using BG Sentinel trap with dry ice in bamboo forest in Damyang-gun, Jeoullanam-do, in South Korea from August to September, 2009. Captured mosquitoes were counted and released every one hour during 25 hours experiment time. The result showed that Ae. albopictus activity began with sun rising at approximately 09:00, with peak in the early evening between 16:00 to 19:00, and ended with sunset at 21:00. Among the several factors affecting on the mosquito activity, light intensity seems to be a main factor. Especially, if the light intensity is over some threshold, it negatively effects on the activity of Ae. albopictus.
The intracellular endosymbiont bacterium Wolbachia is currently considered the most abundant in arthropods. Many Wolbachia manipulate host reproductive systems, it lead to male-killing, cytoplasmic incompatibility, parthenogenesis and feminization of genetic males with large impact on host ecology and evolution in arthropods. In this study, we investigated the distribution of Wolbachia infection in Ae. albopictus according to geographical distribution. We selected 9 areas and collected Ae. albopictus, these areas were distinguished with mountain chain and waterway. Whole genomic DNA were extracted from collected specimens and PCR analysis were accomplished in each specimen using Wolbachia specific primers such as 16S and WSP genes. As a results, we collected 730 Ae. albopictus at least 30 specimens in each area. Wolbachia infection rate showed different patterns between geographical region. Cheonbook, Cheonnam and Yeongdong showed 100% infection rate followed by Jeju (97%), Chungchung (88%), and Gyungnam (85%) with two Wolbachia marker genes. Our results indicated that Ae. albopictus are commonly infected with Wolbachia, it is possible that Wolbachia may act as endosymbiont in Ae. albopictus regardless of geographical region. Although, low infection rate of Wolbachia, we need continuous survey for the evaluation of Wolbachia strain within Ae. albopictus as a vector of dengue fever.
Microsatellite loci are increasingly used as markers in the human, animal and plant genomes. Being highly mutable, microsatellite regions are able to differentiate between related taxa, even at the level of individual isolates in a single species. Studies on mushroom population structure, gene flow and dispersal between natural and cultivated species have become central in breeding programmes and the knowledge of new polymorphic, codominant markers will be a promising avenue to exploit wild genetic resources. The molecular phylogeny in 50 different commercial cultivated strains of Pleurotus eryngii using PCR amplification with URP primers and mitochondrial microsatellite primer was studed. The sizes of the polymorphic fragments obtained were in the range of 200 to 2000 bp. RAPD analysis techniques were able to detect genetic variation among the tested strains. With these isolated PCR amplification with URP primers we intend to analyse the population structure of the P. eryngii species complex and investigate the structure of the basidiomycete genome which deserves. A few single-locus microsatellite markers have been isolated in Pleurotus eryngii and Pleurotus ferulae. This technique is useful in those species where microsatellite loci are rare in the mitochondria.
The mating-type genes control formation of the dikaryon from two haploid strains. These genes are now used in mating-type-assisted breeding programs for economically important mushrooms, especially the oyster mushroom, Pleurotus ostreatus, aiming at high-yield and high-quality standard mushroom production. However, it improves the breeding program when the breeder is able to quickly identify compatible strains in a given set of progeny. The two mating factors with their mating-type loci are used as markers for breeding and have been incorporated in a chromosome mapping investigation. The linkage maps include not only genetic markers such as the mating types that can be cored, but also molecular markers such as PCR-assisted approaches, e.g. RAPD analyses, or RFLP markers. Once mating-type genes within progeny may be more easily identified by the use of PCR-directed cloning of partial mating-type genes. We analyzed homeodomain (HD1 and HD2) and pheromone receptor(rcb1, 2 and 3) genes as molecular markers for breeding using mating type A and B of Pleurotus eryngii and Pleurotus ferulae by direct PCR.
Monochamus alternatus and M. saltuarius were reported as the vectors of Bursaphelenchus xylophilus, pine wood nematode in Korea. According to Kwon et al. (2006), each of 2 species has occupied their own regional distribution : M. saltuarius in southern part including Jeju island and M. alternatus in mid-northern part of Korean peninsula. We measured the supercooling point (SCP) of 2 species (laboratory-reared populations) by each of developmental stages. The SCPs of 2nd, 3rd and 5th instar larvae of M. saltuarius were -7.68±0.19℃, -7.02±0.69℃, -4.93±1.34℃ each of stages. On the other hand, the SCPs of 3rd, 4th, 5th instar larvae and pupae of M. alternatus. were -4.46±1.12℃, -5.94±1.33℃, -7.83±1.44℃, -9.53±1.78℃ each of stages. The SCPs of M. saltuarius larvae generally was lower than that of M. alternatus. The pupae of M. alternatus and 2nd instar larvae of M. saltuarius had the lowest SCP among measured samples. On the other hand, the highest SCP were recorded in 2nd and 5th instar larvae, each. This result shows that regional distribution of 2 beetles may be associated with the adaptation capacity to low temperature represented by the SCP as well as the developmental temperature. However, beetles experimented were not collected from pine forest fields. In further study, we are planning experiments with field populations and all developmental stages.
Pine wilt disease (PWD) is one of the most serious forest tree diseases and now the damaged area covers 7,877 ha and more than 60 cities in Korea. The causal agent of PWD, Bursaphelenchus xylophilus is transmitted by the insect vectors, pine sawyers (Monochamus spp.). Spread of PWD damage and control effect for PWD are directly related to dispersal potential of Monochamus spp. vectors. Recently, harmonic radar technology has been applied as a means for tracking individual dispersal of tagged insects. Tracking insects with harmonic radar system is similar to a mark-and-recapture technique, in which an organism is tagged, released, and recaptured. Our objective is to develop a harmonic radar tracking system by using lightweight tags to investigate dispersal of Monochamus spp., insect vectors. The harmonic radar system consists of two parts: a commercially available, light-weight (1.6 kg), handheld transceiver (RECCO Rescue System) and a small tag that reflects the transceiver signal (917 ㎒) at harmonic frequencies (1,834 ㎒). A tag consists of a miniature diode (Toshiba ISS350) with wires (36-gauge tinned copper) soldered using conductive epoxy on each side to produce a dipole antenna. These tags were evaluated in an open field to assess their maximum detection range, and at tag length of 13 ㎝, the tag was detected at >100 m.
Chrysanthemum white rust, caused by Puccinia horiana, is one of the most destructive fungal diseases in chrysanthemum cultivation worldwide. For increasing efficiency of resistant breeding, molecular markers linked to chrysanthemum white rust resistance gene were developed in pseudo F1 cross population between ‘Puma White’ as susceptible and ‘Dancer’ as resistant using bulked segregant analysis (BSA). Of 280 RAPD primers (Operon 10 mer), 18 primers found to be polymorphic. After screening of these primers in 20 individual lines, only OPI-13520 was selected as closely linked marker to white rust disease resistance. Based on correspondence between phenotypic resistant level and marker in 187 segregation population, the genetic distance between white rust resistance gene and OPI-13520 marker assumed to be 3.8 cM. For OPI-13520 marker conversion into sequence characterized amplified region (SCAR) marker, the amplified fragment of OPI-13520 was purified, cloned and sequenced. Based on the DNA sequence of OPI-13520, SCAR maker was generated and verified in 20 individual lines used in BSA-RAPD.The results showed SCAR marker could be used to identify white rust resistance in chrysanthemum.