Human eryhropoietin (EPO) is acidic glycoprotein hormone that plays key role in hematopoiesis by facilitating differentiation of erythrocyte and formation of hemoglobin (Hb) and is used for the treatment of anemia. Human EPO is consist of 166 amino acids which is modified by three N-glycosylations (24, 38, 83) and single O-glycosylation (126). N-glycosylation is reported to be related to the cellular secretion and activity of EPO. In this study, we examined effects of mutagenesis in glycosylation site of recombinat hEPO for the cellular secretion during production from cultured CHO cell. We produced rhEpo which was cloned by PCR from human liver cDNA (TaKaRa) in cultured CHO cell. Using supernatant of the culture, ELISA assay and western analysis were performed. To estimate biological activity, 20IU of rhuEpo was subcutaneously injected into four ICR mice. After 8 days, HCT level was increased average 13 per cent, RBC was increased ca. 2106//. In disease model Rat (anemia c-kit, WSRC-WS/WS), HCT was increased ca. 12%, RBC was increased ca. 1.6106//. These results suggests that rhEpo we produced has biological activity. To remove glycosylation site by substituting 24, 38, 83, and 126th asparagine (or serine) with glutamic acid, overlapping -extension site-directed mutagenesis was performed. To add novel glycosylation sites, 69, 105th leucine was mutated to asparagine. Mutant EPO construct was transfected into CHO cell. Supernatant of the cell culture was analyzed using ELISA assay with monoclonal anti-EPO antibody (Medac, Germany). Since, several reports for mutagenesis of glycosylation sites showed case-by-case results, we examined both transient expression and stable expression. Addition of novel glycosylation sites resulted no secretion while deletion mutants had little effect except some double deletion mutants (24/83 and 38/83) and triple mutant. We suggest that not single but combination of glycosyl group affect secretion of EPO.

Considerable attention has been focused on the cryopreservation of semen and estrus induction in dog, as consequence of poor productivity caused by long anestrus period, in order to enhance the productivity of youngs and to preserve the breeds. The objectives of this study were to evaluate semen quality after cryopreservation and to evaluate the Pregnancy rate after insemination (AI). Fifty infertilie dogs (age 2∼3 years) were selected for the study and divided into three different estrus induction treatment groups. Group 1: dogs (n=15) were given clomifene (0.1 mg/kg) orally for five days at 12 hr intervals. Group 2: dogs (n=15) were given bromocriptine (50 /kg) orally for five days at 12 hr intervals, followed by single injection intravenously of 500 IU GnRH (Group 3, n=20) when pro-estrus occurred. The rates of pregnancy in estrus inducted dogs mated naturally compared to those inseminated artificially with ejaculated fresh semen and frozen-thawed semen. Estrus detection was performed using the method of vaginal smear and confirmed by the plasma progesterone assay. The ejaculated semen to freeze was exposed to a mixture of Tris extender with cryoprotectant (Trisma, 81 mM: TES, 209 mM: citric acid, 6 mM; glucose, 5 mM; glycerol, 8%) and cryopreserved gradually by slow-cooling at 17 cm above the surface of liquid nitrogen (LN) for 23 min. The motility of frozen-thawed spermatozoa was assessed by phase-contrast microscopy. To assess their viability and acrosome content, spermatozoa were stained with a vital stain and Fluorescence conjugated lectin Pisum Savitum Agglutinin (FITC/PAS), respectively. Pregnancy was confirmed by ultrasonograpy on day 25, 35 and 55 post insemination. The use of fresh semen, the pregnancy rates were observed 66.6, 66.6, 75.0 and 83.3% in natural estrus, clomifene induced, bromocriptine induced and a combination of GnRH and bromocriptine, respectively. The use of frozen-thawed semen, the pregnancy rates were observed 66.6, 33.3, 50.0 and 60.0% in natural estrus, clomifene induced, bromocriptine induced and a combination of GnRH and bromocriptine, respectively. No difference was observed in the number of offspring produced among natural estrus and treated groups inseminated with fresh or frozen-thawed semen. In conclusion, the pregnancy rate of dogs treated with a combination of GnRH and bromocriptine was more effective than use of clomifene or bromocriptine only. In addition, frozen-thawed semen can be used successfully far artificial insemination in dog.

Considerable attention has been focused on the cryopreservation of semen and estrus induction in dog, as consequence of poor productivity caused by long anestrus period, in order to enhance the productivity of youngs and to preserve the breeds. The objectives of this study were to develop a treatment protocol for estrus induction. Fifty infertilie dogs (age 2∼3 years) were selected for the study and divided into three different estrus induction treatment groups. Group 1: dogs (n=15) were given clomifane (0.1 mg/kg) orally for five days at 12 hr intervals. Group 2: dogs (n=15) were given bromocriptine (50 /kg) orally for five days at 12 hr intervals, followed by single injection intravenously of 500 IU GnRH (Group 3, n=20) when pro-estrus occurred. After being treated, the dogs were evaluated for the rates of estrus induction and time interval lapses from treatment to beginning of the pro-estrus. The estrus induction rates were significantly (P<0.05) higher in both group 2 (9/15, 73.3%) and group 3 (16/20, 80.0%) than that of group 1 (9/15, 60.0%), but did not differ in the groups 2 and 3. No differences were observed in the time interval lapses from treatment to beginning of the pro-estrus in group 2 (7.7 1.2 days) and group 3 (6.9 2.0 days), but significantly (P<0.05) shorter than that of group 1 (9.5 2.1 days). In conclusion, the estrus induction rate of dogs treated with a combination of GnRH and bromocriptine was more effective than use of clomifene or bromocriptine only.

This study was carried out that to investigate the effects of amino acids supplemented with culture medium on development of porcine embryos cultured in vitro. Cumulus oocyte complexes (COCs) were cultured in the maturation medium containing hormones (0.5/ LH, 0.5/ FSH and 1/ estradiol-17) for 20-22 h at 39 in an atmosphere of 5% COin air. Subsequently, COCs were cultured in hormone-free maturation medium for 20-22 h. After maturation for 40-44h, oocytes were removed cumulus cells by pipetting and cultured with epididymal sperm for 5 h in the mTBM. Embryos obtained were divided in 4 groups (1) cultured in NCSU 23 containing 0.4% BSA to blastocyst stage(Control), (2) essential amino acids (EA), (3) non-essential amino acids (NA), (4) mixture of essential and non essential amino acid (EA+NA). All treated groups(2-4) were used a glucose free NCSU 23 medium supplemented with pyruvate (0.33 mM), lactate (4.5 mM) to morula stage. From morula to blastocyst stage embryos of all treated groups were cultured in NCSU 23 containing 0.4% BSA. The rates of cleaved oocytes at 48 h after IVF were from 82% to 88% in the groups of control, EA, NA and EA+NA, respectively. The in vitro developmental rates into blastocysts in the groups of EA and EA+NA were significantly (P<0.05) higher than those of group of control (35.1, 35.4 vs. 19.4%, respectively), however, no significant (P<0.05) between control and NA. In conclusion, supplemented with essential amino acid or mixture of essential and non essential amino acid in the culture medium at morula stage increased the rate of development to blastocyst on in vitro produced porcine embryos.

The International Union for Conservation of Nature and Natural Resources (IUCN) considers the western/lowland bongo Tragelaphus eurycerus eurycerus to be a threatened species, and the eastern/mountain bongo Tragelaphus eurycerus isaaci an endangered species［1］. Although extinction is considered by many biologists to be a natural process during evolution, the exponential growth of the human population has drastically and prematurely reduced the numbers and genetic diversity of many species［2］. Species have evolved to adapt to a specific habitat or environment that meet their survival needs. Alteration or destruction of their habitat results in a species becoming incapable of adapting and hence becoming threatened with extinction. A widespread scientific and public consensus has emerged suggesting that governments should assign high priority to the maintenance of biological diversity via habitat preservation and management far species conservation［3］. Unfortunately, the loss of biological diversity far surpasses the available conservation resources and species are lost forever on a daily basis［4］. Notwithstanding the focus on habitat preservation and wildlife management, conservation biologists have also become increasingly interested in using the technologies of reproductive and developmental biology to help manage or rescue endangered species［5］.

A new species, Frankliniella gilva sp. nov. on Gramineae is described with illustrations of external characters from Korea. The species is distinguishable from other related species by the uniformly pale-yellow body, the prolonged head between compound eyes, five ventral pigmented facets on compound eyes, and the absence of mesosternal spinula.

Reasonable and reliable assessment method is one of the most important issues in science education, Partial credits method is an effective tool for assessing students' science inquiry problem solving. The purposes of this study were to classify the Problem solving types based on the analysis of the thinking Process, and how much the related science concept and the science process skills were used in solving science inquiry problems, and to describe the possibility and rationality of the assessment method that gives partial credit 128 high school seniors were selected and their answers were analyzed to identify science concepts they used to solve each problem, and the result was used as the criterion in the scientific concept test development. Also, to study the science inquiry problem solving type, 152 high school seniors were selected, and protocols were made from audio-taped data of their problem solving process through a think-aloud method and retrospective interviews. In order to get a raw data needed in statistical comparison of reliability, discrimination and the difficulty of the test and the production of the regression equation that determines the ratio of partial credit, 640 students were selected and they were given a science inquiry problem test, a science process skills test, and a scientific concept test. Research result suggested it is more reasonable and reliable to switch to the assessment method that applies partial credit to different problem solving types based on the analysis of the thinking process in problem solving process, instead of the dichotomous credit method.

We have studied 73 pre-service science teachers' conceptions about the nature of science (NOS) using 120 true-false test items based on AAAS Benchmarks statements. We have found that participants have inadequate understanding of the NOS, especially in understanding of five categories of conceptions; change and continuity in science, bias in scientific investigations, hypothesis in scientific investigations, things common in science, and science ethics. The result also indicates that there is a difference between primary pre-service teachers and secondary pre-service teachers. From the analysis of consistency, we also found that this inadequate understanding comes from confusion rather than misconception. All the results support that there is a need of intense pre-service teacher education concerning thenature of science.

One of the prime objectives of school science is to help the children learn science concepts and conceptual schemes that will help them understand and interpret their environment. One of the basic scientific concepts is 'Change -everything existing in universe is changing always'. The purpose of this study was to investigate the characteristics of elementary and secondary students' conception of change. The subjects for this study were 489 students in Korea; 111 fourth graders, 95 sixth graders, 140 seventh graders and 143 ninth graders. Four items - mountain, river, ground, sea -were used for investigating students conception of change because representing the nature world in elementary and secondary level. The subjects were asked to check whether each item was changing and to explain each their check. Students' explanations were classified by whether they were sound understanding geologically, or not. The rate of responses that each item was changing was compared by grades and the rate of geological explanations was also compared by grades. Because students' conceptions of change might were effected by time scale, the additional questions that asked students whether the present status of four items were equivalent to the that of several points of time. As a result, the rate of scientific answers and patterns of explanations were similar by grade and the rate of geological understandings was relatively low. The frequencies of concept of change were more dropped as the point of time was closer to present.

Mantle xenoliths in alkali basalt at Boun, the Gansung area and Baegryung Island in South Korea are spinel lherzolites composed of olivine, orthopyroxene, clinopyroxene, and spinel. Minerals show homogeneous compositions. Olivine compositions have Fo89.0 to Fo90.2, low CaO (0.03 to 0.12 wt%), and NiO of 0.34 to 0.40 wt%; the orthopyroxene is enstatite with En89.0 to En90.0 and Al2O3 of 4 to 5 wt%; the clinopyroxene is diopside with En47.2 to En49.1 and Al2O3 of 7.42 to 7.64 wt% from Boun and 4.70 to 4.91 wt% from Baegryung. Spinel chemistry shows a distinct negative trend, with increaeing Al corresponding with decreasing Cr, and Mg# (100Mg/Mg+Fe) and Cr# (100Cr/Cr+Al) of 75.1 to 81.9 and 8.5 to 12.6, respectively. The equilibrium temperatures of these xenoliths, taken as the average obtained from those of Mercier (1980) and Sachtleben and Seck (1981), lie between 970 and 1020˚C, and equilibrium pressures derived from Mercier (1980) fall within the range of 12 to 19 kbar (i.e., 42 to 63 km). These temperatures and pressures are reinforced by considerations of the Al-isopleths in the MAS system (Lane and Ganguly, 1980), as adjusted for the Fe effect on Al solubility in orthopyroxene (Lee and Ganguly, 1988). The equilibrium temperatures and pressures of xenoliths, as considered in P/T space, belong to the oceanic geotherm, based upon the various mantle geotherms presented by Mercier (1980). This geotherm is completely different from continental geotherms, e.g., from South Africa (Lesotho) and southern India. Mineral compositions of spinel-lherzolites in South Korea and eastern China are primitive; paleo-geotherms of both are quite similar, but degrees of depletion of the upper mantle could vary locally. This is demonstrated by eastern China, which has various depleted xenoliths caused by different degrees of partial melting.

The bees belonging in the tribe Anthidiini from Korea were revised, five genera six species were recorded and given the key to genera and species. Amens them, L. malaisei Popov and S. melanura Cockerell were new to Korea.

Muscaphis stroyani (Smith, 1980) and Muscaphis escherichi (Borner, 1939) were collected from Mt. Baekdu-san, North Korea. Fundatrix and alate emmigrant female of the Korean specimens are described. Host plants and brief biology of each species are discussed and the biometric data for fundatrix and alate emmigrant female are given. A key to species for fundatrix and alate emmigrant female is also presented

To identify genes implicated in the control of pluripotency as well as characteristics of stem cells, we analyzed expression profiles of genes derived from mouse morulas, blastocysts, embryonic stem cells, mesenchymal stem cells, and uterus tissue using cDNA microarray. Comparative analyses of their expression profiles identified putative clones that expressed specifically in specific samples or not in a specific sample. The expression pattern of these condidate clones was analyzed using RT-PCR and non-radioactive in situ hybridization. Functional annotation of these clones on pluripotency and stem cell plasticity is in ongoing. These studies may further our understanding on the nature of the stem cells and molecular mechanisms underlying many facets of mammalian development and differentiation.

Three species of Macrosiphum(Unisitobion) are recognized from the Korean Peninsula, among which M.(Unisitobion) sorbi matsumura, 1918 and M.(Unisitobion) perilae(Zhang, 1988), comb. nov. are new to the Korean Peninsula. Morphological characteristics are discussed with the microscopic photos. Two species, M.(Unisitobion) sorbi and M.(Unisitobion) perillae are redescribed. The subgeneric position of each species is discussed. The host plants, brief biology, and a key to all known species of the subgenus are also presented.