• Title/Summary/Keyword: Species differences

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Evaluation of Pharmacokinetics of Simvastatin and Its Pharmacologically Active Metabolite from Controlled-Release Tablets of Simvastatin in Rodent and Canine Animal Models

  • Shanmugam, Srinivasan;Ryu, Jae-Kuk;Yoo, Sun-Dong;Choi, Han-Gon;Woo, Jong-Soo
    • Biomolecules & Therapeutics
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    • v.19 no.2
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    • pp.248-254
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    • 2011
  • Biotransformation of pharmacologically inactive lactone prodrug simvastatin (SV) into pharmacologically active simvastatin ${\beta}$-hydroxy acid (SVA) exhibits inter-species differences due to variations in amount and activity of esterase enzymes. In this study, we investigated the pharmacokinetics (PK) of SV and its metabolite SVA following oral doses of SV from controlled-release (CR) tablets and immediate-release (IR) tablets in rodent and canine animal models that features different esterase activity. In rat PK study, no SV was detected in plasma for both formulations due to rapid hydrolysis of SV into SVA by plasma esterase. Besides, no significant differences in PK parameters of SV or SVA were observed between both species. In dog PK study, the relative oral bioavailability of CR tablets in terms of SV was 72.3% compared to IR tablets. Regarding formulation differences in dogs, CR tablets exhibited significantly lower $C_{max}$ (p<0.05), and higher $T_{max}$ (p<0.01) and MRT (p<0.01) for both SV and SVA compared to IR tablets. Accordingly, CR tablets of SV with prolonged drug release profiles in both species might be a potential candidate for a more effective delivery of SV with reduced side effects. Besides, similar PK parameters of SV and SVA in both species despite variation in enzyme activities suggested involvement of equally potent biotransformation pathways in these animal species.

Morphological Discretion of Basidiospores of the Puftball Mushroom Calostoma by Electron and Atomic Force Microscopy

  • Kim, Mi-Sun;Kim, Ki-Woo;Jung, Hack-Sung
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1721-1726
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    • 2007
  • Comparative morphology among species of the genus Calostoma, including C. cinnabarina, C. ravenelii, and C. japonicum, was investigated by scanning electron microscopy and atomic force microscopy. Spore morphology of C. cinnabarina and C. ravenelii showed no dramatic differences by light microcopy and scanning electron microscopy. To differentiate these species, atomic force microscopy was employed. Quantitative analysis of the surface roughness of basidiospores revealed subtle differences in height fluctuation at the nanometer scale between the species of Calostoma. Basidiospores of C. cinnabarina had a relatively rougher surface than those of C. ravenelii at $2.0{\times}2.0\;{\mu}m^2$ scan areas.

Composition of the Gastrointestinal Microflora in Korean Breast-fed and Formula -fed Newborn Infants (수유방법에 따른 한국 신생아의 장내균총 조성에 관한 연구)

  • 문수재
    • Journal of Nutrition and Health
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    • v.31 no.1
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    • pp.80-87
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    • 1998
  • Intestinal microflora in 17 breast-fed(BF) and 14 formula-fed (FF) newborn infants at about 1 week after birth were investigated to determine the floral differences of the two lactation groups. The fecal conditions were significantly different between the two groups in that the number of subjects who showed watery feces, and the times of defecation per day, were higher in the BF group. In addition, the mean fecal PH of the BF group was lower than that of the FF group. The dominant species in the BF groups which showed the highest count among the species of microflora was bifidobacteria , while the dominant species in the FF group was streptococci. The frequency of staphylococci and the count of bifidobacteria were significantly higher in the BF group. However, the frquencies of streptococci and Peptococcaceae were higher in the FF group. Through the differences were not significant, the frequency of bvifidobacteria and the count of staphylococci were higher in BF group, whereas the frequencies of bacteriodes, clostridia, enterobacter and the count of clostridia were higher in FF group.

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A Study on the Landscaping of Elementary Schools (초등학교의 조경에 관한 조사 연구 - 대구시 초등학교를 중심으로 -)

  • Suh, Eung-Chul
    • Journal of the Korean Institute of Educational Facilities
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    • v.5 no.3
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    • pp.91-97
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    • 1998
  • The purpose of this study is to investigate elementary school landscaping. The landscaping has intrinsic value for educational purpose as well as an open space resource in urban area. Four elementary schools in Taegu were surveyed and analyzed to identify the ratio of greenery, green volume and its maintenance. The result can be summarized as follows: 1. While 58 species of trees were quoted all over the text book, 17 to 52 species were found in each school and only few species were always dominant in each school. 2. The greenery and green volume were insufficient in terms of quantity and inadequate in placement, and there were differences in landscaping quality and quantity between schools. However the differences were not associated with the age of schools. 3. Functional implementations of landscaping technique(for example, environmental control) were needed for future landscaping of elementary schools.

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pH Response Pathways in Fungi: Adapting to Host-derived and Environmental Signals

  • Selvig, Kyla;Alspaugh, J. Andrew
    • Mycobiology
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    • v.39 no.4
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    • pp.249-256
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    • 2011
  • Microorganisms are significantly affected when the ambient pH of their environment changes. They must therefore be able to sense and respond to these changes in order to survive. Previous investigators have studied various fungal species to define conserved pH-responsive signaling pathways. One of these pathways, known as the Pal/Rim pathway, is activated in response to alkaline pH signals, ultimately targeting the PacC/Rim101 transcription factor. Although the central signaling components are conserved among divergent filamentous and yeast-like fungi, there is some degree of signaling specificity between fungal species. This specificity exists primarily in the downstream transcriptional targets of this pathway, likely allowing differential adaptation to species-specific environmental niches. In this review, the role of the Pal/Rim pathway in fungal pH response is discussed. Also highlighted are functional differences present in this pathway among human fungal pathogens, differences that allow these specialized microorganisms to survive in the various micro-environments of the infected human host.

Crown Competition on the Relation of Crown Width to Diameter at Breast Height of Trees (樹木의 胸高直經과 樹冠너비와의 關係로 본 樹冠競爭)

  • Park, Bong Kyu;Ok-Kyung Kim
    • The Korean Journal of Ecology
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    • v.8 no.4
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    • pp.197-200
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    • 1985
  • The relations of crown width and DBH for Pinus densiflora, Pinus rigida, Pinus koraiensis, and Ginkgo biloba were accomplished to estimate the level of crown competition. Measurements of the relations revealed that crown width and DBH were highly correlated for the same species. Also it seems that these relations are independent of age and site quality. The results of regression analysis were as follow: P. densiflora, Y=0.3477X+0.3828 r=0.95 p. rigida, Y=0.3537X+0.1645 r=0.95 P. koraiensis, Y=0.2895X+0.6310 r=0.92 G. biloba, Y=0.4360X+0.0995 r=0.90 The significant differences between G. biloba and pine species seems due to their structural differences of crown formation according to tree species. As results of computing Maximum Crown Area and Crown Competition Factor as indices of crown competition, they indicated that P. densiflora would grow better under the natural conditions.

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Geographic Variation of Granulilittorina exigua (Littorinidae, Gastropoda) in Korea Based on the Mitochondrial Cytochrome b Gene Sequence

  • Song, Jun-Im;Suh, Jae-Hwa;Kim, Sook-Jung
    • Animal cells and systems
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    • v.4 no.3
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    • pp.267-272
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    • 2000
  • Partial sequence of the mitochondrial cytochrome b gene was analyzed to investigate genetic variation from 10 geographic populations of Granulilittorina exigua in Korea. The sequence of 282 base pairs was determined by PCR-directed silver sequencing method. The sequences of two species within the genus Littorina reserved in NIH blast search were utilized to determine geographic variations of species referred. The levels of mtDNA sequence differences were 0.00-2.54% within populations and 0.71-4.43% between populations. There were four amino acid differences between representative species of the genera Granulilittorina and Littorina, but no differences within populations of the genus Granulilittorina. The UPGMA and the N-J trees based on Tamura-Nei genetic distance matrix were constructed, which showed that the genus Granulilittorina was divided into three groups such as eastern (even exception for Tokdo population), southern, and western regional populations. The degrees of genetic divergence within populations of each group were p=0.021, p=0.019, and p=0.018, respectively. The divergence between the eastern and southern populations was p=0.032, showing closer relationship than with the western populations (p=0.052). Based on the diverged time estimation, the eastern and southern populations of Granulilittorina exigua in Korea diverged from the western populations about 2.1 MYBP, and the eastern and southern populations diverged from each other about 1.3 MYBP.

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One new species and three records of cytheroid ostracods (Crustacea, Ostracoda) from Korea

  • Karanovic, Ivana;Yoo, Hyunsu;Tanaka, Hayato;Tsukagoshi, Akira
    • Journal of Species Research
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    • v.6 no.spc
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    • pp.38-50
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    • 2017
  • This study describes a new species of cytheroid ostracod, Paradoxostoma koreana sp. nov., collected in Korea. In addition, three other cytheroid ostracods, P. setoense Schornikov, 1975, Loxoconcha pulchra Ishizaki, 1968, and Ishizakiella miurensis (Hanai, 1957), are reported with brief descriptions and images. Paradoxostoma setoense and L. pulchra were previously only known from Japan, while I. miurensis was previously reported from Korea. Here, we describe variability in hemipenis morphology observed in the Korean population. The new species is closely related to several East Asian species, but its sister species is P. rhomboideum Okubo, 1977. The primary difference between the new species and P. rhomboideum is morphology of the distal projections of the hemipenis, but minor differences exist in the details of the cheatotaxy of other appendages. This report also provides a list of all East Asian Paradoxostomatidae.

Effect of Carbohydrates on in vitro Shoot Growth of Various Prunus Species

  • Cheong, Eun Ju;An, Chanhoon
    • Korean Journal of Plant Resources
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    • v.28 no.3
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    • pp.357-362
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    • 2015
  • Carbohydrate sources are one of important factors associated with macro- and micro nutrients and phytohormones in vitro culture medium for shoot growth. The optimal carbohydrates for eight species of the genus Prunus which are economically important fruit crop was evaluated at the initiation and elongation stages. All carbohydrate seemed utilized for the bud break and leaf growth at the early stage of culture. However, shoot elongation and fresh weight of species tested were superior in the medium containing 90 mM of fructose or glucose rather than sucrose. There was no difference between glucose and fructose. Adventitious shoots from the axillary buds were induced in most species but no significant differences were observed except for two species (P. salicina ‘Shiro’ and P. tomentosa). These result demonstrated that glucose and fructose were suitable carbohydrate sources for diverse Prunus species than sucrose, although the response to the carbohydrates in the medium were slightly different in the species.

Species Diversity of Forest Vegetation in Togyusan National Park (덕유산 국립공원 삼림식생의 종 다양성)

  • Kim, Chang-Hwan;Bong-Seop Kil
    • The Korean Journal of Ecology
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    • v.19 no.3
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    • pp.223-230
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    • 1996
  • Five measurements of species diversity (richness index, diversity index, evenness index, dominance index and species sequences-importance curve) and their relationships with sltitude, tree age and community type were studied in $T\v{o}gyusan$ National Park, Korea. Altitude and tree age were the major variables explaining the differences of species diversity in the whole forest. Species richness index, diversity index and evenness index of Quercus mongolica and Pinus densiflora communities were lower than those of Carpinus laxiflora, Q. serrata, Fraxinus mandshurica, Q. mongolica - P. densiflora communities than that in the other communities. The species sequence-importance curve of the forest communities in $T\v{o}gyusan$ coincided with the ideal curve calculated by the lognormal-distribution theory.

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