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Distributions and Pollution History of Heavy Metals in Nakdong Estuary Sediments (낙동강 하구역 퇴적물 중금속의 분포와 오염의 역사 추정)

  • Cho, Jin-Hyung;Park, Nam-Joon;Kim, Kee-Hyun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.4
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    • pp.285-294
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    • 2000
  • In order to determine the horizontal and vertical distributions of metals and prospect the recent metal pollution history in Nakdong Estuary, we took surface and core sediments. Maximum value of organic matter occurs at the upstream site located 4 km from Nakdong barrage, and the concentration of trace metals (Zn, Cu, and Pb etc.) decrease seaward in the estuary. The sedimentation rates, based on $^{210}$Pb$_{ex}$ and $^{137}$Cs activities, were 0.34 cm/yr in inside of barrage (core 1) and 0.25 cm/yr in Changrim (core 4). Sediment mixing layer does not exist in core 1, where anoxic condition is known to be prevail. The topmost sediment layer of core 4 (<3.5 cm) is severely mixed. At sites 1 and 4, concentrations of Cu slowly increased during the period of 1920-1970, rapidly increased during 1970-1990, and followed by slight decrease after 1990. Zn contents increased in early 1960s and peaked in 1993, and followed by decrease after 1990s. Pb has increased continuously since early 1970s. At the downstream of the barrage, Cu and Zn have increased in the topmost layer. The trend of increase of Cu is evident after 1950 (11 cm in sediment depth). Overall trend of heavy metal concentration clearly indicates the pollution has been increasing after the construction of the barrage.

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A Study on status of school health and analysis of factors affecting school nursing activities in the secondary school in Seoul (서울지역 국민학교(國民學校) 양호교사의 학교간호업무(學校看護業務) 수행정도(遂行程度)에 관(關)한 연구(硏究))

  • Kim, Eun Hee
    • Journal of the Korean Society of School Health
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    • v.1 no.2
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    • pp.50-65
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    • 1988
  • This study was conducted in order to grasp the condition of about the school nurse's service and to offer the basic materials of improving the school health service. The objects were comprised of 98 volunteered school nurses who take service in the elementary school. The material of this study was the questionaire suited to the purpose of this research which has been made through studying references and this questionaire has been corrected and revised three times. All the questionaire written by school-nurses. The results are as follows; 1. General features of the objects of study Average age was 35.9 and average career was 9.2 years. Except working as school-nurse, the past career was that average clinical-field was 3.4 years and health service was 4 months. Their educational level was as high as 72.4% of the objects were graduated from above 3 years college and 89.8% were married. 76.5% have religions and 94.8% were working at with national and public schools. 99.0% were doing only nursing service. 2. The conditions of the school health resources. The ratio of school-nurse to students was one to 2630. School-nurse to classes, one to 49.3, and school-nurse to teachers, one to 54. For total amount of a year budget of school health, from three hundred thousands to fifty nine hundred thousands won was most common. Expenses for purchasing medicine were used most. 58.2% of school-nurses hasn't known a year budget. There was an organization for school health in 74.2% of schools. 42.9% of nursing rooms were in the center of school and 88.8% were on first floor. Nursing room were used alone without being used by another purpose and the room size of 71.6% was below 10 pyong. 3. The conditions of school health service Average users of nursing room were 413 a month. The most of them had digestive trouble. Sending letters to home was 15.9 times a year. The most contents of letters was about health education. Object spent much time managing nursing room. 4. The degree of school health service When 2 points was given to "perform" and 1 point was to "not perform" the total average was 1.75, health education 1.89, environmental management 1.86, plan of project and evaluation 1.83, management of nursing room 1.82, health management 1.78, run of school health organization 1.32. 5. Correlation between the school health services and variables (1) The part of project plan and evaluation of school health service has relationship to existence or none-existence of school health organization (P<0.01), past health service career (P<0.05), number of classes (P<0.01), number of students (P<0.01), sending letters to home about health education (P<0.01) and number of users (P<0.05). (2) The part of nursing room management has relationship to ages (P<0.05) past clinical career (P<0.05), number of classes (P<0.05), number of students (P<0.05) and sending letters to home about health education (P<0.01). (3) The part of health education has relationship to existence or none-existence of school health organization (P<0.05), past clinical career (P<0.05), the ratio of health management to school nurse's all work (P<0.05) and the ratio of health education to school nurse's all work (P<0.01). (4) The part of environmental management to ages (P<0.01), career as a school-nurse (P<0.01), salary step(P<0.01), sending letters to home about health education (P<0.01), sending all letters to home (P<0.001), the ratio of health management to school nurse's all work (P<0.05), the ratio of health education to school nurse's all work (P<0.05) and area of school-nurse's room to be used. (5) The part of school health organization management to number of classes (P<0.05). (6) The part of health management to number of classes (P<0.05), sending letters to home about health education (P<0.001), sending all of letters to home (P<0.01) and the ratio of health management to school nurse's all work (P<0.05). (7) The part of school health service to ages (P<0.05), past clinical career (P<0.05), past health career (P<0.01), number of classes (P<0.05), number of student (P<0.05), sending letters to home about health education (P<0.05), sending all letters to home (P<0.05), the ratio of health management to school nurse's all work (P<0.05), the ratio of health education to school nurse's all work (P<0.01) and area of school - nurse's room to be used (P<0.05). ## Suggestion for further studies are as follows. 1. School-nurse should exert herself to advance a quality to take care of school population's health. 2. It is necessary that systematic support required to keep school population's health. 3. Home, school and community should make efforts cooperatively and the proper roles of students, teachers, health team members and parents must be achieved.

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Biological Control of Fusarium Stalk Rot of Maize Using Bacillus spp. (Bacillus spp.를 이용한 옥수수 밑둥썩음병의 생물학적 방제)

  • Han, Joon-Hee;Park, Gi-Chang;Kim, Joon-Oh;Kim, Kyoung Su
    • Research in Plant Disease
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    • v.21 no.4
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    • pp.280-289
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    • 2015
  • Maize (Zea mays L.) is an economically important crop in worldwide. While the consumption of the maize is steadily increasing, the yield is decreasing due to continuous mono-cultivation and infection of soil-borne fungal pathogens such as Fusarium species. Recently, stalk rot disease in maize, caused by F. subglutinans and F. temperatum has been reported in Korea. In this study, we isolated bacterial isolates in rhizosphere soil of maize and subsequently tested for antagonistic activities against F. subglutinans and F. temperatum. A total of 1,357 bacterial strains were isolated from rhizosphere. Among them three bacterial isolates (GC02, GC07, GC08) were selected, based on antagonistic effects against Fusarium species. The isolates GC02 and GC07 were most efficient in inhibiting the mycelium growth of the pathogens. The three isolates GC02, GC07 and GC08 were identified as Bacillus methylotrophicus, B. amyloliquefaciens and B. thuringiensis using 16S rRNA sequence analysis, respectively. GC02 and GC07 bacterial suspensions were able to suppress over 80% conidial germination of the pathogens. GC02, GC07 and GC08 were capable of producing large quantities of protease enzymes, whereas the isolates GC07 and GC08 produced cellulase enzymes. The isolates GC02 and GC07 were more efficient in phosphate solubilization and siderophore production than GC08. Analysis of disease suppression revealed that GC07 was most effective in suppressing the disease development of stalk rot. It was also found that B. methylotrophicus GC02 and B. amyloliquefaciens GC07 have an ability to inhibit the growth of other plant pathogenic fungi. This study indicated B. methylotrophicus GC02 and B. amyloliquefaciens GC07 has potential for being used for the development of a biological control agent.

Functional Analysis of Bacillus subtilis Isolates and Biological Control of Red Pepper Powdery Mildew Using Bacillus subtilis R2-1 (Bacillus subtilis 균주의 기능성 분석 및 이를 활용한 고추 흰가루병 방제)

  • Kim, Yong-Ki;Hong, Sung-Jun;Shim, Chang-Ki;Kim, Min-Jeong;Choi, Eun-Jung;Lee, Min-Ho;Park, Jong-Ho;Han, Eun-Jung;An, Nan-Hee;Jee, Hyeong-Jin
    • Research in Plant Disease
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    • v.18 no.3
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    • pp.201-209
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    • 2012
  • The multi-function of 18 Bacillus subtilis isolates collected from agricultural extension centers of local government and National Academy of Agricultural Science was investigated by measuring their antifungal activities against five plant pathogens, such as Rhizoctonia solani, Colletotrichum acutatum, Fusarium oxysporum, Magnaporthe oryzae and Phytophthora capsici, phosphorus solubilization ability, production of indole acetic acid (IAA) and siderophore, and nitrogen fixation. The B. subtilis isolates showed antifungal activity against several plant pathogens and nitrogen fixation activity, and produced siderophore and IAA. They could control pepper powdery mildew (Leveillula taurica), but there was no difference in control efficacy among the B. subtilis isolates. In fields, the control efficacy of B. subtilis R2-1 ($10^8$ cells/ml) was compared with two microbial fungicides, Q-pect and Topsid. In 2009, the control efficacy of B. subtilis R2-1 (37.7%) was lower than that of Topsid (47.6%), but higher than that of Q-pect (25.7%). In 2010, the control efficacy of B. subtilis R2-1 (83.3%) was higher than that of Topsid (67.9%). In order to elucidate mode of action of B. subtilis R2-1 for controlling pepper powdery mildew, spore germination rates of pepper powdery mildew pathogen collected on treated leaves was investigated when suspensions of B. subtilis R2-1 and two microbial fungicides (Q-pect and Topsid) were foliar-sprayed. They highly suppressed spore germination of the pathogen with inhibition values of 84.2% for B. subtilis R2-1, 97.9% for Q-pect and 94.7% for Topsid. Further study on the mass-culturing method and formulation is needed for development of a microbial fungicide.

Isolation and Characterization of Starch-hydrolyzing Pseudoalteromonas sp. A-3 from the Coastal Sea Water of Daecheon, Republic of Korea (대한민국 대천 해안에서 분리한 전분 분해능을 갖는 Pseudoalteromonas sp. A-3 균주의 특징 및 동정)

  • Chi, Won-Jae;Park, Da-Yeon;Jeong, Sung-Cheol;Chang, Yong-Keun;Hong, Soon-Kwang
    • Microbiology and Biotechnology Letters
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    • v.39 no.4
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    • pp.317-323
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    • 2011
  • Strain A-3, an amylase-producing bacteria, was isolated from coastal seawater near Daecheon in the Republic of Korea. It was seen to possess a single polar flagella and grow well, on ASW-YP agar plates, at temperatures of between $20-37^{\circ}C$. However, it grew more slowly at the temperatures of $15^{\circ}C$ and $40^{\circ}C$. Similarly, it was observed to grow abundantly, in an Artificial Sea Water-Yeast extract-Peptone (ASW-YP) liquid medium, in a pH range of 6-9, but not grow at pHs of 4-5 and a pH of 10. Strain A-3 was noted as being close to Pseudoalteromonas phenolica O-$BC30^T$, Pseudoalteromonas luteoviolacea $NCIMB1893^T$, Pseudoalteromonas rubra $ATCC29570^T$, and Pseudoalteromonas byunsanensis $FR1199^T$, with 98.30%, 97.86%, 97.78%, and 97.25% similarities respectively, in its 16S rRNA sequence. A phylogenetic tree revealed that strain A-3 and P. phenolica O-$BC30^T$ belong to a clade. However, strain A-3 differed from P. phenolica O-$BC30^T$ in relation to a number of physiological characteristics. Strain A-3 exhibited no growth above 5% NaCl concentrations, no utilization of D-glucose, D-mannose, D-maltose, or D-melibose, and no lipase (C-14) activity. All of these properties strongly indicate that strain A-3 is distant from P. phenolica O-$BC30^T$ and thus led us to name it Pseudoalteromonas sp. A-3. Pseudoalteromonas sp. A-3 produces ${\alpha}$-amylase throughout growth. Maximal amylase activities of 144.48 U/mL and 149.20 U/mL were seen at pH 7.0 and $37^{\circ}C$, respectively. Pseudoalteromonas sp. A-3's high, stable production of ${\alpha}$-amylase in addition to its biochemical features, such as alkalitolerance, suggest that it is a good candidate for industrial applications.

Inhibitory Efficacy of Dystaenia takeshimana Extract on iNOS, COX-2 Protein and mRNA Expression in Raw 264.7 Cell (Raw 264.7 세포에서 섬바디나물 추출물의 iNOS, COX-2 단백질 및 mRNA 발현 억제 효과)

  • Lee, Jin-Young;Yoo, Dan-Hee;Joo, Da-Hye;Chae, Jung-Woo
    • Microbiology and Biotechnology Letters
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    • v.44 no.4
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    • pp.571-576
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    • 2016
  • In this study, the anti-inflammatory activities of the 80% ethanol extract of Dystaenia takeshimana (DT) were investigated using Raw 264.7 cells treated with lipopolysaccharide (LPS). The effect of DT extract on the production of pro-inflammatory factors (iNOS, COX-2) in LPS-stimulated Raw 264.7 macrophages was examined. The cytotoxic effect of DT extract on macrophage cells (Raw 264.7) was examined by the 3-[4, 5-dimethyl-thiazol-2-yl]-2, 5-diphenyl-tetrazoliumbromide (MTT) assay. Treatment with DT extract showed 100% or more cell viability at the concentration $1,000{\mu}g/ml$. The inhibitory effect of DT extract on protein expression of inducible NOS (iNOS) and cyclooxygenase-2 (COX-2) was measured by western blotting using the concentrations 50, 100, and $500{\mu}g/ml$, with ${\beta}-actin$ used as the positive control. Consequently, the protein expression of iNOS, and COX-2 as observed by western blotting, was decreased by 56%, 61.6%, respectively with $500{\mu}g/ml$ DT extract. Inhibition of iNOS and COX-2 mRNA expression was measured by reverse transcription- polymerase chain reaction (PCR) using DT extract concentrations 50, 100, and $500{\mu}g/ml$, with GAPDH used as a positive control. Consequently, the mRNA expression of iNOS and COX-2 as observed by reverse-transcription-PCR was decreased by 77.9% and 83.3%, respectively at $500{\mu}g/ml$ concentration of DT extract. In conclusion, DT extract may affect inflammatory factors as a potential anti-inflammatory agent.

Application of Earthworm Casting-derived Biofilter Media for Hydrogen Sulfide Removal (지렁이 분변토를 이용한 생물담체가 충전된 바이오필터에 의한 황화수소 제거)

  • Yoo, Sun-Kyoung;Lee, Eun-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.7
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    • pp.820-825
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    • 2007
  • Earthworm casting was the natural fertilizer that contained high concentrations of nutrients such as nitrogen, phosphate and potassium and of over $10^8$ CFU/ml of microorganisms. Greater than 80% of feed was excreted through the fermentation by the intestinal enzyme, after worm had eaten feeds such as fallen leaves and rotten roots under the ground. Also, the soil structure of casting was known to be very efficient in the aspects of the porosity, the water permeability, and deodorizing activities. In this research, the biofilter packed with a biomedia made of casting and waste polyurethane foam, a binder, which helped to improve the durability and perpetuity of casting, was investigated to degrade malodorous hydrogen sulfide gas. The biomedia had no need of extra supply of nutrients and of microbial inoculations. On the beginning of the operations, it showed 100% removal of hydrogen sulfide gas without lag phase. At SV of 50 $h^{-1}$, hydrogen sulfide gas from the outlet of the biofilter was not detected, when inlet concentration increased to 450 ppmv. After that, removal efficiency decreased as increasing inlet hydrogen sulfide concentration. Hydrogen sulfide removal was maintained at almost 93% until inlet concentration was increased up to 950 ppmv, at which the elimination capacity of $H_2S$ was 61.2 g $S{\cdot}m^{-3}{\cdot}h^{-1}$. Maximum elimination capacity guaranteing 90% removal was 61.2, 65.9, 84.7, 89.4 g $S{\cdot}m^{-3}{\cdot}h^{-1}$ at SV ranging from 50 $h^{-1}$ to 300 $h^{-1}$, but was 59.3 g $S{\cdot}m^{-3}{\cdot}h^{-1}$ at SV of 400 $h^{-1}$. The results calculated from Michaelis-Menten equation revealed that $V_m$ increased from 66.04, 88.96, 117.35, 224.15, to 227.54 g $S{\cdot}m^{-3}{\cdot}h^{-1}$ with increasing space velocity in the range of 50 $h^{-1}$ to 400 $h^{-1}$. However, saturation constant$(K_s)$ decreased from 79.97 ppmv to 64.95 and 65.37 ppmv, and then increased to 127.72 and 157.43 ppmv.

Effect of Temperature on the Nitrogen Removal of Municipal Wastewater in a Pilot-scale Moving Bed Biofilm Reactor with Waste-tire Media (폐타이어 담체를 이용한 파일럿 규모 유동상 생물막 공정에서 하수의 질소제거에 미치는 온도 영향)

  • Park, Woon-Ji;Ahn, Johng-Hwa;Lee, Chan-Ki
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.5
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    • pp.507-516
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    • 2008
  • This research was conducted to elucidate the effect of temperature on the nitrogen removal of municipal wastewater with waste-tire media. The experiments were carried out in laboratory-scale batch reactor and pilot-scale moving bed biofilm reactor filled at a 0.15 filling ratio with waste-tire media, respectively. In batch tests, specific nitrification rate(SNR) with media was 3.4 mg NH$_4^+$-N/g Mixed-Liquor Volatile Suspended Solid(MLVSS)$\cdot$hr, compared with 1.7 mg NH$_4^+$-N/g MLVSS$\cdot$hr without media. In pilot-scale test with media, total nitrogen removal efficiency increased from 53 $\pm$ 8% to 76 $\pm$ 5% as the temperature increased from 9$\sim$10$^{\circ}C$ to 20$\sim$24$^{\circ}C$. At the temperature of 9$\sim$10$^{\circ}C$, 10$\sim$20$^{\circ}C$, and 20$\sim$24$^{\circ}C$, the SNRs were 0.8 $\pm$ 0.5, 3.1 $\pm$ 1.9, and 3.4 $\pm$ 2.1 mg NH$_4^+$-N/g MLVSS$\cdot$hr and the specific denitrification rates(SDNR) were 0.6 $\pm$ 0.2, 1.1 $\pm$ 0.6, 1.4 $\pm$ 0.6 mg NO$_3^-$-N/g MLVSS.hr, respectively. The overall activities of biomass in anaerobic, anoxic, and oxic zones at 20$\sim$24$^{\circ}C$ increased to 22, 20, and 15%, compared with those at 9$\sim$10$^{\circ}C$, respectively. The activity distribution of Nitrosomonas and Nitrobacter also increased with the increase of temperature.

Anti-inflammation Activities of Cultured Products from Suspension Culture of Aloe vera Callus (Aloe vera Callus 현탁배양 생성물의 항염증 활성)

  • Kim, Myung Uk;Cho, Young Je;Lee, Shin Young
    • Journal of Applied Biological Chemistry
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    • v.56 no.3
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    • pp.157-163
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    • 2013
  • Cultured products (callus and exopolysaccharide) were obtained from suspension culture of Aloe vera callus, and the extracts of callus were further prepared with cold water or 60% ethanol solution. The ethanol extract of callus (AC) and exopolysaccharide (ACP) of 10 mg/mL exhibited the relatively higher suppression activity of 43.2-52.1% against hyaluronidase activity. Thus, their anti-inflammatory effects were further investigated using animal cell (Raw 264.7) in vitro. Though AC shows a slight suppression effect of cell survival rate (97%) using MTT assay in the presence of $400{\mu}g/mL$ AC- dimethyl sulfoxide (DMSO), cell growth promotion was observed in the other samples of lower levels. It indicates that the ethanol extract of Aloe callus rarely affect cell survival rate in the ranges ($200-400{\mu}g/mL$) used in the study. Using Griess reagent, the suppression of NO production by the aloe callus extract was analyzed by measuring the amount of the nitrite produced in Raw 264.7 culture activated by lipopolysaccharide (LPS). As a result, supplementation of AC-distilled water (DW) and AC-DMSO produced higher levels of NO than the positive control LPS. However, the NO suppression effect by ACP-DW was so intense that lower amount ($80-100{\mu}g/mL$) suppressed NO production to the level of the control. The effect was attributed to the expression of the iNOS. Then, Raw 264.7 cells were stimulated with the LPS and expression of COX-2 protein level was analyzed depending on the Aloe suspension culture product treatment. The results showed that the ACP-DW supplemented medium did not express COX-2 by itself, and LPS stimulated COX-2 expression was slightly decreased. On the other hand, realtime-PCR analysis of the expression of inflammatory cytokine showed that IL-$1{\beta}$ and TNF-${\alpha}$ expression was highly suppressed in the ACP- distilled water supplemented medium.

On the Secretion and Functions of Equine Chorionic Gonadotropin (말의 융모성 성선자극 호르몬의 분비와 기능)

  • Min, K.S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.2
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    • pp.125-142
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    • 2000
  • 13). Analysis of a purified preparation of eCG revealed that its $\beta$ -subunit consists of 149 amino acids, which was confirmed by the molecular cloning of its cDNA. There seem to be at least four to six, or even as many as 11, O-glycosylation sites on the extended C-tenninal region of the eCG $\beta$-subunit. Interestingly, eCG is a unique member of this family, as it appear to be a single molecule that possesses both LH- and FSH-like activities. Using the cDNA prepared from mRNA extracted from equine placental and pituitary tissues, we cloned the cDNA of eCG $\alpha$- and $\beta$ -subunits and eFSH $\beta$ -subunit. The mRNA expression of each subunit seems to be independently regulated, which may account for differences in the quantities of $\alpha$ - and $\beta$ -subunits in the placenta and pituitary. Thus, eCG is a distinct molecule from the view points of its biological function and glycoresidue structures. Recombinant eCGs including the mutants which lack oligosaccharides will be useful tools for analyzing the structure-function relationships of gonadotropins in the horse as well as other species. Similar experiments will also clarify the proposed structure and biological functions for the glycoprotein hormones. These experimental are now possible, and hopefully a resolution of the existing controversy will be forthcoming in the near future.

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